Dissertations / Theses: 'Brucellosis Brucellosis Brucellosis Brucellosis'

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Hysenaj, Lisiena. "Alterations of hematopoiesis during brucellosis." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0251.

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La brucellose est une maladie qui se transmet de l’animal à l’homme. Elle est causée par la bactérie Brucella. Lors de ma thèse, j’ai montré que Brucella persiste dans les cellules de la moelle osseuse des animaux infectés. Ces observations sont très importantes car la moelle est un organe responsable de la génération des cellules du système immunitaires et c’est la principale niche des cellules souches hématopoïétiques. Au cours de ma thèse, j'ai montré que la protéine de la membrane externe 25 de Brucella (Omp25) est capable de lier au récepteur SLAMF1, une molécule exprimée par les cellules souches hématopoïétiques. Cette interaction conduit à la génération d'un plus grand nombre de cellules myéloïdes par les cellules souches hématopoïétiques. Les cellules myéloïdes sont la niche préférée de Brucella. Ainsi, cette stratégie permet à la bactérie d'envahir l’hôte et d'établir une infection chronique de longue durée. SLAMF 1 apparaît comme une nouvelle cible thérapeutique pour le contrôle des maladies infectieuses chroniques, ce qui représenterait une avancée importante dans la génération de nouveaux médicaments Brucellosis is a disease that is transmitted from animals to humans. It is caused by the pathogenic bacterium Brucella. During my thesis, I showed that Brucella persists in the bone marrow cells of infected animals. These observations are very important because the bone marrow is an organ of the immune system responsible for the generation of the immune cells, as it is the principal niche of hematopoietic stem cells. During my thesis, I showed that Brucella outer membrane 25 (Omp25) is able to bind SLAMF1, a hematopoietic stem cell molecule. This interaction leads to the production of more myeloid cells by the hematopoietic stem cell. Myeloid cells are the favorite niche of Brucella. Thus, this strategy allows the bacteria to invade the host and establish a long lasting chronic infection. SLAMF 1 appears as a new therapeutic target for controlling chronic infectious diseases, which would represent an important advance in the generation of new drugs

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Roth, Felix. "The development of brucellosis control in Mongolia." Thesis, London School of Hygiene and Tropical Medicine (University of London), 2007. http://researchonline.lshtm.ac.uk/682361/.

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Previous economic analysis of brucellosis control in Mongolia provided a basis for further research. It was observed that there was a long tradition of brucellosis control in Mongolia but little knowledge on its effect on the spread of disease. This thesis addressed this gap and analysed the relationship between stated surveillance policy, the brucellosis prevalence in animals, and the brucellosis incidence in humans. The aim was to contribute to better understanding of the brucellosis surveillance policies applied in Mongolia and their effectiveness, and to draw conclusions and recommendations for control of brucellosis. Four aims were formulated providing steps for investigating the research question. The first two aims focused on (i) the establishment of the epidemiological patterns of brucellosis in Mongolia over the time period 1966 to 2002, and on (ii) the provision of a historical overview of the different strategies applied to the control of brucellosis in Mongolia over the same time period. The third aim was to assess the interactions between the spread of brucellosis and the surveillance strategies, and finally the forth aim was to issue recommendations about future surveillance policies for brucellosis. It was found that the published figures reflected the Brucellosis abortus incidence in the population that could be serologically tested. However, the population at risk (herders) with the main burden of disease, and suffering from Brucellosis melitensis, was underdiagnosed and not treated properly, additionally, the immunisation cam- paigns in small ruminants did not reach the critical vaccination level for eradication. Therefore, the diagnosis and treatment of Brucellosis melitensis in humans has to be assured at Soum (district) level. The current immunisation campaign has to be monitored and evaluated, and the knowledge of brucellosis in humans has to be recognised by policy makers, physicians and general population.

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Ullah, Aman. "Epidemiology of bovine brucellosis in Sindh, Pakistan." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/17983.

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Brucellosis is endemic in many livestock worldwide especially developing countries. The aims of this study were to estimate the seroprevalence of bovine brucellosis and risk factors associated with the seropositivity in rural and peri-urban buffaloes and cattle populations of Sindh. Firstly, a cross sectional study was conducted to estimate the seroprevalence of bovine brucellosis in cattle and buffaloes of Sindh province, Pakistan. Serum samples (2600) were tested using Rose Bengal Plate Test. The overall seroprevalence of brucellosis in Sindh province was 13.96% (95% C.I.; 11.55 - 16.37). Of the 917 herds tested, 232 or 25.30% herds (95%C.I.; 22.51-28.24) were positive for brucellosis. The adult animals were 2.05 (95% C.I.; 1.14-3.68, P= 0.02) times more likely to test positive for brucellosis. The animals in a peri-urban dairy production system were 2.07 times (95%C.I.; 1.09-3.90, P = 0.03) times more likely have brucellosis. The species or sex of animal did not appear to affect the risk of seropositivity in cattle or buffalo in this population. Secondly, a cross sectional survey was conducted to understand the structure and composition of farms, animal husbandry and management practices in peri-urban dairy colonies in Karachi and farmers’ awareness of zoonoses. The mean herd size was 93.58 animals and 88.01% of these animals were female buffaloes. Of 326 farms surveyed, only 37.42% were able to associate animals with transmission of diseases in human. The characteristics of peri-urban dairy farms in Karachi are discussed. Thirdly, the value of FTA® cards in detecting the Brucella DNA in milk samples was estimated by determining the detection limits of genus specific ERI PCR assay for FTA® cards and comparing the PCR results from whole sediments taken from culturing pooled milk samples with taking sediment on FTA® cards. The detection limits of this method ranged from 6.6 x 103 cfu/ml for B. abortus to 7.17 x 106 cfu/ml for B. suis. Assuming the results of ERI PCR for the whole sediment as gold standard (method 1), the method using sediment on FTA® cards as test samples (method 2) showed a diagnostic sensitivity of 81.44% (95% C.I.; 75.54-87.33) but a poor diagnostic specificity of 42.86% (95%C.I.; 16.95-68.78). The kappa value, κ, was 0.14 (p = 0.02) demonstrating a poor agreement between the two methods. Lastly, 181 bulk milk samples were used to estimate the herd level prevalence of bovine brucellosis in Landhi dairy colony, Karachi. The ERI PCR was used to test these samples. The herd prevalence was estimated as 92.26% (95% C.I.; 88.34-96.19). For each level (50 animals) increase in herd size, the risk of herd being brucellosis positive increases by 2.38 times. The herds that have a male animal for breeding are 0.09 times less likely to have brucellosis. The history of abortion, presence of small ruminants or the regions of animal purchase don’t appear to have any association with the risk of brucellosis at a herd level in this population at LDC, Karachi. A high seroprevalence of bovine brucellosis in livestock population in Sindh and a very high herd level prevalence in peri-urban dairy farms in particular poses a serious threat to the public health and livestock production in Sindh, Pakistan.

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Treanor, John Joseph. "THE BIOLOGY AND MANAGEMENT OF BRUCELLOSIS IN YELLOWSTONE BISON." UKnowledge, 2012. http://uknowledge.uky.edu/biology_etds/7.

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Disease management along the boundaries of wildlife reserves is a growing conservation problem worldwide, as infected wildlife can migrate outside protected areas and pose a threat to livestock and human health. The bison Bison bison population in Yellowstone National Park has long been infected with Brucella abortus, the bacterium causing bovine brucellosis. Concern over migratory bison transmitting B. abortus to cattle herds on lands adjacent to Yellowstone has led to proposals for bison vaccination. Model simulations suggest that vaccination is unlikely to eradicate B. abortus from Yellowstone bison but could be an effective tool for reducing the level of infection and eliminating unpopular management practices such as lethal culling. The culling of Yellowstone bison to reduce the risk of brucellosis transmission to cattle is negatively affecting long-term bison conservation because of difficulties in diagnosing actively infected animals. Age-specific serology and B. abortus culture assays from slaughtered bison were used to develop a diagnostic tool to estimate whether particular animals are infective. Findings suggest that active B. abortus infection is age-dependent, which allows true infection probabilities to be estimated based on age and quantitative diagnostic tests. Active brucellosis infection was associated with below-average nutritional condition, with the intensity of B. abortus infection being influenced by seasonal reductions in dietary protein and energy. The reproductive strategy of Yellowstone bison is linked with the seasonal availability of food, which increases bison fitness but may have consequences for B. abortus infection. Seasonal food restriction may also influence the ability of vaccinated bison to recall protective immune responses when later exposed to B. abortus. The rate of fat metabolism was an important factor influencing cell-mediated responses. Thus, individual variation and the seasonal availability of food may reduce vaccine efficacy when vaccination is applied at the population level. Consequently, effective management practices will require a diverse range of integrated methods, which include maintaining separation of livestock and wildlife, managing habitat to reduce brucellosis transmission, and reducing disease prevalence in wildlife. The long-term success of these management practices will depend on sound science and support of the stakeholders involved.

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Dajer-Abimerhi, Alfredo Francisco Javier. "Bovine brucellosis : serodiagnosis, epidemiology and control in Yucatan, Mexico." Thesis, Royal Veterinary College (University of London), 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428571.

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Bruce, Mieghan. "The impact of brucellosis in Albania : a systems approach." Thesis, Royal Veterinary College (University of London), 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.701674.

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Buhrman, Dianne L. "The behavior and effects of Brucella abortus rough strain RB51 in mice and cattle." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/45940.

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Brucella abortus st. RB51 is a rough mutant of smooth st. 2308 devoid of O-side chain and resistant to rifampin. The purpose of this investigation was to study the behavior and effects of viable st. RB51 organisms in inoculated mice and cattle and to further substantiate the lack of O-side chain antigens in this strain. A single injection of live st. RB51 persisted in BALB/C mice up to 28 days. A secondary exposure was cleared in 7-21 days. One or 2 injections of st. RB51 did not induce detectable titers of anti-O-side chain antibodies, although antibody titers to st. RB51 whole cell and cytoplasmic antigens were detected. Mice infected with st. RB51 alone or followed by infection with st. 2308, demonstrated a very strong reaction to a 14-18 Kd antigen which was believed to be the core of the LPS complex. When st. RB51 was administered after injection of st. 2308 the response to the core determinants were inhibited. One vaccination with st. RB51 was able to significantly protect mice against challenge with st. 2308 at one and four weeks post challenge. Two st. RB51 vaccinations were able to protect mice as well as one vaccination at one week post challenge but protection increased by four weeks post challenge. Strain RB5l was able to survive in cattle a for at least twenty-two days. The organism remained stable, rifampin resistant, and may have induced minor amounts of transient anti-O-side chain antibodies in some cows late in the experiments. Master of Science

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Hegazy, Yamen Mohammed. "Ruminant brucellosis in Egypt : frequency, distribution and potential control strategies." Thesis, Royal Veterinary College (University of London), 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558965.

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Arenas, Gamboa Angela Maria. "Evaluation of microencapsulation as an improved vaccination strategy against brucellosis." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1384.

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Smith, Garrett Paul. "Immunocontraceptive vaccines against brucellosis and population growth in feral swine." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/77987.

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Feral swine are a nuisance species across the United States that costs around $1.5 billion each year in agricultural, environmental, and personal property damages. In the last ten years the population of feral swine is estimated to have quadrupled and novel population control methods are needed. Furthermore, feral swine are known carriers of zoonotic diseases such as brucellosis, which threatens both livestock biosecurity and public health. Recombinant multimeric gonadotropin-releasing hormone (mGnRH) has been previously used as a subunit vaccine to induce immunocontraception in feral pigs. However, potent adjuvants and large amounts of purified antigen are needed to elicit a robust anti-GnRH immune response and current delivery methods are limited. Brucella suis strain VTRS2 can be used as a novel platform to deliver mGnRH without the use of antibiotic resistant markers. Strain VTRS2 was created by deletion of the LPS biosynthesis gene wboA as well as the leuB gene required for leucine biosynthesis inside the nutrient-depleted intracellular environment occupied by Brucella. Mutations in wboA are known to attenuate Brucella strains such as the vaccine strain B. abortus RB51, however strain RB51 is rifampin resistant and has poor efficacy in swine. Strain VTRS2 confers significant protection against B. suis challenge in mice and additionally shows evidence of protection in feral swine. Furthermore, the mGnRH antigen can be delivered using the pNS4 plasmid (which expresses leuB under its native promoter) thus maintaining the plasmid in strain VTRS2 under leucine-deficient conditions while expressing recombinant antigen in the host. The murine model was used to determine the clearance kinetics of strain VTRS2-mGnRH and to measure vaccine efficacy against challenge by virulent B. suis 1330. Subsequently the effects of the VTRS2-mGnRH vaccine on fertility were assessed in breeding trials in mice. Strains VTRS2 and VTRS2-mGnRH were found to be protective against virulent Brucella suis challenge. Strain VTRS2-mGnRH elicited an anti-mGnRH antibody response in vaccinated mice, though an effect on fertility was not observed. An improved vaccine against brucellosis in swine, which also confers immunocontraception without the introduction of antibiotic resistance, could become an important tool in the management of this nuisance invasive species. Ph. D.

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Thompson, Riley Jacob. "Discovery and Evaluation of Immunogenic Antigens for Bovine Brucellosis Serodiagnostics." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42349.

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Brucella spp. are zoonotic infectious agents, primarily of livestock, that cause the disease brucellosis. Bovine brucellosis, caused by Brucella abortus, is of greatest concern due to the disease’s significant economical and public health impact. Canada fully eradicated bovine brucellosis from domesticated cattle herds in 1985, however, continued surveillance through screening for B. abortus exposure is paramount to the maintenance of bovine brucellosis eradication nationwide. The Canadian Food Inspection Agency (CFIA) is responsible for the surveillance of bovine brucellosis outbreaks in Canada and the maintenance of eradication. Current B. abortus serodiagnostics and serological screening is mostly based on the detection of antibodies against Brucella lipopolysaccharide (LPS), a highly immunogenic component of the outer cellular membrane. Such tests face difficulties with false positive results due to cross reactivity with other Gram-negative bacteria that produce LPS. The purpose of the research presented here was to address this issue through identifying new B. abortus protein antigens for the improvement of serological test specificity. In this study, 101 candidates were identified through predictive bioinformatic analyses and selected for immunogenic evaluation. While none of the expressed candidates displayed positive serological activity with in-house brucellosis positive bovine serum panels, the workflow presented here can be used for continued research and the assessment of more proteins from B. abortus and other bacterial pathogens.

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Hermoza, Guerra María Angela. "Manifestaciones clínicas de la infección por Brucella en el Hospital Nacional Daniel Alcides Carrión durante 1999-2000." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2003. https://hdl.handle.net/20.500.12672/1864.

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Introducción: El Callao que es la segunda provincia con mayor incidencia por brucelosis en el Perú. El Hospital Nacional “Daniel Alcides Carrión” (HNDAC) es hospital de referencia del Callao. Objetivos: Evaluar las características clínicas más frecuentes de la brucelosis en pacientes hospitalizados y ambulatorios en el HNDAC, evaluando según el tipo de brucelosis y sus complicaciones. Material y Métodos: Estudio retrospectivo descriptivo aplicado; abarca todo paciente con diagnóstico de brucelosis confirmada con serología y/o cultivo, atendidos en el HNDAC durante los años 1999-2000. Resultados: Se encontró 193 casos, 134 (69,4%) con brucelosis aguda, 56 (29%) con brucelosis subaguda, 03 (1,6%) con brucelosis crónica. Hubo 66 (34,2%) casos hospitalizados y 127 (65,8%) ambulatorios. Las manifestaciones clínicas más frecuentes en hospitalizados: fiebre (95,5%), hiporexia (78,8%), astenia (63,6%), artralgias (57,6%), nauseas (47%), vómitos (40,9%), palidez (31,8%), petequias (7,6%) y como complicaciones: anemia (83,3%), plaquetopenia (39,4%), leucopenia (36,4%), osteoarticular (16,7%), hepática (34,9%), la totalidad de púrpura, pancitopenia, orquitis, uveítis, colitis requirieron hospitalización. En ambulatorios: fiebre (77,2%), astenia (48,8%), cefalea (42,5%), anemia (50,4%), plaquetopenia (41,7%), alteración hepática (11,8%), osteoarticular (7,9%). En brucelosis aguda, se hospitalizaron 36,6%, se encontró fiebre (91,8%), astenia (60,4%), hiporexia(53,7%), anemia (66,4%), plaquetopenia (37,3%) leucopenia (27,6%), alteración hepática (20,9%), osteoarticular (5,2%), parotiditis (1,5%), pancitopenia (1,5%). En brucelosis subaguda se hospitalizaron 30,4%, se encontró: fiebre (67,9%), artralgias (42,9%), astenia (39,3%), hiporexia (32,1%), lumbalgia (28,6%), petequias(7,1%), epistaxis (7,1%), anemia(53,6%), plaquetopenia (50%), púrpura (8,9%), complicación osteoarticular (21,6%), hepática (16,1%). En brucelosis crónica: artralgias (66,7%), hiporexia (33,3%), lumbalgia (33,3%), complicación osteoarticular (66,7%), hepática (33,3%), ningún hospitalizado. Tuvieron control posterior 146 pacientes (75,6%). Se encontraron 27 (14,0%) recaídas, todos con sintomatología de menos de 02 meses, sobresale: fiebre (66,7%), artralgias (40,7%), plaquetopenia(55,6%), artritis periférica (11%) y artritis mixta (3,7%). Se especificó el tratamiento recibido en 72 pacientes (37.3%) de estos 17,3% fueron ambulatorios y 75,8% hospitalizados y se especificó el alta sólo en 04 casos (2,1%). Conclusiones: Los pacientes hospitalizados presentan mayor número de manifestaciones clínicas y de complicaciones. La brucelosis aguda es la forma clínica más frecuente, se presentan síntomas de compromiso general y menor complicación sobresale la hemática y hepática. La brucelosis subaguda tiene más signos hemorragíparos y mayor número de complicación especialmente hematológica y osteoarticular. En la brucelosis crónica sobresale las artralgias, todos con alguna complicación. Las recaídas acuden con menos de 02 meses de nuevos síntomas, presentan mayor numero de artralgias y artritis periférica. Existe un inadecuado registro de tratamiento y seguimiento. Tesis de segunda especialidad

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Joly, Damien Oliver. "Brucellosis and tuberculosis as factors limiting population growth of northern bison." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ63882.pdf.

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Commander, Nicola Jane. "An investigation of novel DNA based vaccines for protection against brucellosis." Thesis, London School of Hygiene and Tropical Medicine (University of London), 2005. http://researchonline.lshtm.ac.uk/1300446/.

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This thesis describes design, construction and evaluation in a BALB/c mouse model, for five novel Brucella specific DNA vaccines. Brucellosis is worldwide zoonosis of economic significance that poses a significant threat to both animal and human health. Vaccination of livestock can be valuable for reducing transmission and facilitating control. Development of an efficacious non-living vaccine is therefore a valuable goal in brucellosis research. Five candidate antigens were identified within the Brucella melitensis 16M genome. In silico selection was supported by confirming transcription of the selected genes from cultured Brucella, and evidence of candidate protein immunogenicity in Brucella infected sheep. Eukaryotic and prokaryotic expression plasmids were constructed for each candidate antigen. The protective efficacy of six DNA vaccine constructs was evaluated in a BALB/c model of brucellosis. From this evaluation, two protective antigens were identified for further study: Invasion protein B and the 25 kDa outer membrane protein. The DNA vaccines p-omp25 and p-ialB were shown to have equivalent protective efficacy in the mouse model to that achieved through vaccination with the live vaccine strain Rev.1. DNA vaccine mediated protection was associated with production of specific antibodies and priming of both CD4+ and CD8+ IFN-y secreting cells. High numbers of CD8+ cells were observed for the p-omp25 vaccine, whereas CD4+ cells and antibodies were more prevalent following pialB vaccination. The vaccines were found to be most effective when three homologous booster vaccinations were used. Single dose vaccination afforded only modest levels of protection. Attempts to improve delivery of DNA vaccines through adsorption of DNA to cationic liposomes was partially successful in that there was a notable increase in specific humoral immune responses. However, these increases were not associated with increased cell mediated immunity or protective efficacy.

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Cotterill, Gavin G. "Disease Ecology and Adaptive Management of Brucellosis in Greater Yellowstone Elk." DigitalCommons@USU, 2020. https://digitalcommons.usu.edu/etd/7709.

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Brucellosis is a bacterial infection that primarily affects livestock and can also be transmitted to humans. In the Greater Yellowstone Ecosystem (GYE), elk (Cervus canadensis) and bison (Bison bison) are habitual carriers of Brucella abortus, which arrived to the region with cattle over a century ago. The disease was eliminated from cattle in the United States through widespread control efforts, but is now periodically transmitted back to cattle on open rangelands where they can come into contact with fetal tissues and fluids from disease-induced abortions that occur among elk during the late winter and spring. In Wyoming, south of Yellowstone National Park, there are 23 supplemental feedgrounds that operate annually and feed the majority of the region’s elk during a portion of the winter. The feedgrounds are controversial because of their association with brucellosis and may be shuttered in the future in part due to the arrival of chronic wasting disease. Using data collected at these feedgrounds, this study investigates the role of winter feedgrounds in the ecology of this host-pathogen relationship: it evaluates the full reproductive costs of the disease to affected elk, how herd demography influences pathogen transmission, and assesses management strategies aimed at reducing pathogen spread among elk. Using blood tests for pregnancy status and brucellosis exposure in female elk, I demonstrated a previously undocumented fertility cost associated with the pathogen which is not due to abortions, but which nearly doubles the estimated fertility cost to affected individuals. I also built mechanistic transmission models using time-series disease and count data from feedgrounds. Within that framework, I assessed various management actions including test-and-slaughter of test-positive elk, which I found to be counterproductive due to rapid recovery times and the protective effects of herd immunity. The overall picture that emerges of winter feedgrounds is one of imperfect practicality driven by social and political consideration, not pathogen control. These results illustrate the underappreciated importance that recruitment and population turnover have on the transmission dynamics of brucellosis in elk, a pathogen which itself flourishes in the reproductive tracts of individual animals and thus impacts vital rates at the population level. Together, this study contributes to the field of disease ecology using a unique long term disease data set of free-ranging wild ungulates.

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Jain, Neeta. "Approaches towards therapeutic development against chronic brucellosis in a mouse model." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77039.

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Brucellosis is the most common zoonotic disease worldwide. The intracellular localization of Brucella hinders the action of drugs that poorly cross cell membrane barriers. Additionally, when the immune response fails to clear the infection, chronic brucellosis ensues that becomes more challenging to treat with antibiotics. Therefore, two approaches, intracellular drug delivery and immunostimulation, have been explored in this dissertation, with an aim to develop a better therapeutic against Brucella infection in mice. First, to overcome the cell membrane barriers, drug loaded nanoparticles were tested to treat B. melitensis infection in mice. Gentamicin loaded block-ionomer complexes (BICs) and magnetite block-ionomer complexes (MBICs) were tested in vitro and along with clusters of MBICs (MBIClusters) were tested in vivo as tools to deliver gentamicin intracellularly. While these complexes showed very high efficacy compared to free gentamicin against Brucella in macrophage cell culture, they failed to show similar efficacies in mice. Histopathological examination of kidneys from mice treated with MBICs or MBIClusters showed deposition of brown pigment-laden macrophages in peri-renal adipose tissue and the pigment was confirmed as MBICs or MBIClusters based on special staining for iron. Additionally, it was found that doxycycline-gentamicin (DG) treatment results in better clearance of Brucella from infected mice compared to doxycycline alone. Secondly, two vaccine candidates, irradiated B. neotomae (IBN) and outer membrane vesicles (OMVs), were tested as immunostimulants to treat chronic B. melitensis infection in mice in combination with antibiotics. The non-ionic block co-polymer Pluronic P85, when mixed with OMVs as an adjuvant showed significantly higher protection against B. melitensis challenge in vaccinated mice compared to those vaccinated with OMVs alone. When tested as immunostimulants, there was no additive effect of vaccines and antibiotics on Brucella clearance from mice. However, IBN enhanced the production of IFN-γ while OMVs were associated with enhanced antibody production. This enhancement in the immune system resulted in the control of Brucella growth after the end of treatment. When given without antibiotics, vaccine alone failed to clear any Brucella from infected mice. The use of these vaccine candidates in combination with antibiotics shows a potential to prevent relapses in cases of brucellosis. Ph. D.

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Fluegel, Amanda M. "Validation of diagnostic assays and development of molecular epidemiological tools for brucellosis." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1594477821&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Salih, Harith Mohammed Saleem. "Brucellosis in Iraq: epidemiology, present status, and challenges in controlling the disease." Thesis, Kansas State University, 2010. http://hdl.handle.net/2097/6240.

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Master of Science Department of Diagnostic Medicine/Pathobiology Gary A. Anderson Brucellosis is one of the major endemic zoonotic diseases worldwide, and it has history dating back to 1937 in Iraq when it was first isolated by an Iraqi physician. In order to establish a solution for the continuous devastating impacts of the disease in humans and livestock, the Brucellosis Control Program was established in 1995. The main responsibilities of this program were setting and implementing the appropriate strategies for controlling the disease. After the war in 2003, the United Nation organization for Food and Agriculture (FAO) developed a strategic plan to control the disease. The main goal of the project was to improve productivity in the livestock sector and reduce the prevalence of disease in small ruminants (sheep and goats) to less than 2%, and less than 0.2% in cattle and buffalo. Achieving such goals ultimately would reduce the disease incidence among the human population from more than 27.2 cases/100,000 persons in 2002, to less than 4 cases/100,000 people within 15 years. A serological surveillance was conducted and revealed the apparent prevalence of the disease in sheep and goats, cattle, buffalo, and camels was 6.51%, 1%, 1.48%, and 0.02%, respectively in Iraqi governorates except the three northern governorates of Kurdistan province . Based on surveillance results, a vaccination policy was the only appropriate strategy that could be chosen to control the disease. Four vaccination campaigns were implemented in 2006, 2007, 2008, and 2009, with a total number of vaccinated animals each year at 10099972, 4698482, 753153, and 1833482 head, respectively. The primary satisfactory outcome of the program was the apparent decline in livestock abortions leading to obvious increases in productivity. Regarding the incidence of brucellosis among the human population, the apparent decline in the middle and south of Iraq began with the vaccination phase of the control program in 2006. The results represented a significant decrease in human cases after only four vaccination campaigns of a program that was intended to continue for 15 years.

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Al, Nakkas Aref Fakher Hassan Ali. "A polymerase chain reaction assay for the diagnosis of human brucellosis in Kuwait." Thesis, London School of Hygiene and Tropical Medicine (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325112.

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Kunda, John Stephen. "The epidemiology of human brucellosis in the context of zoonotic diseases in Tanzania." Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/29840.

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The study was carried out in Arusha and Manyara regions, Tanzania with the objectives of determining the burden of disease caused by brucellosis, health seeking behaviour and clinical characteristics of brucellosis cases, risk factors for human brucellosis and to evaluate the different diagnostic armoury for human brucellosis. The objectives were achieved through a cross-sectional survey, a hospital based clinical study and a case-control study. Particular problems were observed with the diagnosis and treatment of brucellosis. No standardized diagnostic and treatment protocols were observed. Tests used showed low sensitivities and brucellosis mimicked other febrile conditions common in the study area such as malaria, typhoid, joint diseases and tuberculosis making diagnosis of brucellosis even more difficult. Patients on the other hand delayed to go to hospital which carried a poor prognosis during treatment. In cross-sectional survey brucellosis was found to be more common in agropastoral areas, but during hospital based study it was found to be more common in pastoral than in agropastoral areas. The burden caused by brucellosis is clearly underestimated in Tanzania. More effort on health education and improved diagnosis need to be put.

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Manhica, Anabela da Piedade. "The prevalence of brucellosis in cattle, sheep and goats in Maputo Province, Moçambique." Diss., University of Pretoria, 2009. http://hdl.handle.net/2263/27114.

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Brucellosis is a constraint to livestock production in Moçambique. Reproductive failure due to brucellosis has been reported in the country and abortions occur in cattle, sheep and goats on many of the farms in Maputo Province of Moçambique. Brucellosis is an infectious disease affecting mainly sexually mature animals and is caused by organisms of the genus Brucella. Brucella abortus is the species that mainly affects cattle throughout the world, while Brucella melitensis affects mainly goats and sheep. Control of bovine brucellosis using B. abortus S19 vaccine was undertaken before the civil war in Moçambique which started in 1978 and ended in 1992. During this period the vaccination status of animals was not known. The diagnosis of brucellosis is mainly based on serological surveys and conflicting results obtained previously emphasized the need for additional studies. The aims of this research were to determine the prevalence of brucellosis in cattle, goats and sheep due to B. abortus and B. melitensis in five districts of Maputo Province based on serology, and to assess the relationship between abortions and reproductive failure occurring in the study area by isolation of Brucella organisms or nucleic acid detection. A total of 971 adult beef and dairy cattle, 752 goats and 260 sheep from the study area were tested for Brucella antibodies using the Rose Bengal test (RBT), indirect ELISA and complement fixation test (CFT). Milk from 85 dairy cows and tissue samples from 32 cows and bulls from Gaza and Inhambane provinces slaughtered in Maputo municipal abattoir and Machava abattoir, and an aborted foetus were also examined. All serological test results for small stock were negative. An overall apparent prevalence of 14.0% (n=971) was found in beef and dairy cattle in the study area based on a 95% confidence interval. The highest prevalence was observed in Manhiça District (27.4% (n=180)) with a significant difference compared to other districts (p<0.05). The lowest prevalence was observed in Magude District (7.1% (n=241)). The prevalence in the remaining districts were 14.5% (n=138) in Matutuine, 8.7% (n=173) in Moamba and 14.6% (n=239) in Boane. Apparent prevalences of 15.5% (n=161) in small, 14.0% (n=578) in medium and 12.9% (n=232) in large livestock production sectors where found in the study area with no significant differences (p>0.05) between them. B. abortus was isolated from the spleen of an aborted foetus. A PCR amplification product of 600bp was generated from this isolate 584/05 and from the organs of five slaughtered cows using primers ISP1 and ISP2 for Brucella genus-specific sequences. The isolate 584/05 was confirmed as a B. abortus field strain when fragments of 498bp and 178bp were generated using a PCR assay for differentiation of B. abortus field strains and vaccine strains 19 and RB51. A correlation was made between the 584/05 isolate and serum from the cow that aborted. The results confirmed that the isolate was not a vaccine strain. The results from this study will supplement existing epidemiological data and aid brucellosis control programmes in Moçambique. Copyright Dissertation (MSc)--University of Pretoria, 2009. Veterinary Tropical Diseases unrestricted

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Fernandes, Dancella Marie. "Cell-mediated immunity as the basis for resistance or susceptibility to murine brucellosis /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487859313346275.

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MacMillan, Alastair. "The bovine immune response following Brucella vaccination and infection and the development of a discriminatory test." Thesis, University of Surrey, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313252.

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Baloglu, Simge. "Assessment of the Expression of Brucella Abortus Heat Shock Protein, Groel, in Vaccinia Virus to Induce Protection Against a Brucella Challenge in Balb/C Mice." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36943.

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B. abortus is an intracellular facultative bacterial pathogen which causes abortion in cattle and undulant fever in humans. Cattle vaccines such as B. abortus strains 19 and RB51 are live vaccine strains which protect approximately 75% of the vaccinated animals. No effective vaccines are available for the prevention of brucellosis in humans. We are developing vaccinia virus recombinants expressing various B. abortus proteins to prevent brucellosis in susceptible mammalian species. In this work the B. abortus groEL gene encoding the antigenic heat shock protein GroEL was subcloned into vaccinia virus via homologous recombination. Expression of the GroEL protein in vaccinia infected cells in-vivo was confirmed by immunoblotting. Groups of 5 female BALB/C mice were injected with the vaccinia recombinant or appropriate positive and negative control vaccines. Mice were bled and their humoral immune responses assessed. In addition, mice were challenged with virulent B. abortus strain 2308 and protection measured by the rate of splenic clearance of live Brucella. In spite of demonstrating specific GroEL antibodies in recombinant vaccinia injected mice, no significant level of protection was demonstrable. Preliminary lymphocyte transformation assays were carried out to establish if a cell mediated immune response to GroEL was induced in the vaccinated animals. Master of Science

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Poff, Sherry Ann. "Expression of Bacillus Anthracis Protective Antigen in Vaccine Strain Brucella Abortus Rb51." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/10039.

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Bacillus anthracis is a facultative intracellular bacterial pathogen that can cause cutaneous, gastrointestinal or respiratory disease in many vertebrates, including humans. Commercially available anthrax vaccines for immunization of humans are of limited duration and do not protect against the respiratory form of the disease. Brucella abortus is a facultative intracellular bacterium that causes chronic infection in animals and humans. As with other intracellular pathogens, cell mediated immune responses (CMI) are crucial in affording protection against brucellosis. B. abortus strain RB51 has been shown to be useful in eliciting protective cell mediated immunity and humoral responses against Brucella in cattle and other animal species. Since the protective antigen (PA) of B. anthracis is known to induce protective antibodies, it was decided that the objective of this research was to test whether the gene encoding PA could be expressed in Brucella producing a bivalent vaccine to protect against both brucellosis and anthrax. The pag gene was transcriptionally fused to promoters of genes encoding superoxide dismutase or heat shock protein groE, subcloned into a broad host range plasmid (pBBR1MCS) and shown to express in E. coli by immunoblotting using antiserum specific for PA. The immunoblot results revealed that E. coli produced a PA protein of the expected size. In addition, the culture medium was shown to contain the same PA protein using immunoblotting. These results show that E. coli is capable of expressing B. anthracis PA in both the cellular and extracellular forms. The pBB/PA plasmid was used to transform B. abortus RB51 and CmR clones screened for the expression of PA by immunoblotting. Twenty clones of strain RB51/pBBSOD were show to express a 30kDa PA protein. Three clones of strain RB51/pBBGroE-PA were shown to express a 63-83kDa protein as detected by antiserum specific for PA. Using the A/J mouse, an immunocompromised vertebrate model, immunization and challenge studies were performed. Preliminary results demonstrate that the bivalent vaccine is capable of producing protection against a live challenge with B. abortus and some protection against live non-disease producing spores of B. anthracis. Master of Science

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Vaz, Yolanda Maria. "Analysis of policies for the eradication of brucellosis from sheep and goats in Portugal." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319249.

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Rajasekaran, Parthiban. "Development of an Antibiotic Resistance Free Bivalent Vaccine Against Swine Brucellosis and Swine Influenza." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/77310.

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Livestock across the world contract several infectious diseases of both bacterial and viral origin. Swine brucellosis caused by Brucella suis and swine influenza caused by Influenza A virus affect both domestic and feral swine populations. Both the diseases have zoonotic potential to cause disease in humans with serious complications apart from inflicting huge economic losses. Infected feral swine can also act as a source of spread and outbreak where the disease is not endemic. At present, there is no vaccine available for swine brucellosis. The currently used swine influenza vaccine may not be effective against influenza strains like the recent H1N1 strain that caused a pandemic. To develop an effective bivalent vaccine for swine against these two diseases, a leucine auxotroph of the USDA approved vaccine B. abortus strain RB51 was constructed along with leuB gene complementing plasmid pNS4 to over-express antigens from Brucella and influenza. This antibiotic resistance free system over-expressed Brucella derived antigens SOD, L7/L12 and WboA in three different constructs. Against a virulent challenge of B. suis, the candidate vaccine strain over-expressing both SOD and WboA protected mice more significantly than the control group and was also found to be better protective than other candidate vaccine strains over-expressing either SOD and L7/L12 together or SOD alone. Immunoassays (ELISA) suggested that the protection afforded is Th1 type mediated immune response, as cytokine IFN-γ and IgG2a antibody sub-isotype was observed in the splenocyte culture supernatant and serum samples respectively. The strain RB51leuB platform was not expressing influenza derived antigens Hemagglutinin (HA) and Nucleoprotein (NP) when screened for expression by immunoblot. Influenza antigens, HA, NP and ectodomain of matrix protein M2e, were not found to be expressing even after optimizing their codon usage to suit Brucella tRNA preference. However, RT-PCR showed that the influenza genes mRNA were produced. In conclusion, this dissertation describes the construction of an environmentally safe antigen over-expression platform and successful employment of the system as a candidate vaccine in protecting mice against B. suis challenge. This new platform is a potential candidate for developing vaccines against other infectious diseases of livestock. This document also discusses alternate strategies for expressing influenza antigens in a Brucella platform. Ph. D.

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Poff-Reichow, Sherry Ann. "Development of Brucella abortus RB51 as a Vaccine to Protect Against Brucellosis and Anthrax." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/11144.

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Bacillus anthracis is a facultative extracellular bacterial pathogen that causes cutaneous, gastrointestinal or respiratory disease in many vertebrates, including humans. Commercially available anthrax vaccines for immunization of humans are known to provide protection of limited duration and may not protect against the respiratory form of the disease. Commercially available live vaccines for animals have been shown to cause disease in certain species. Brucella abortus is a facultative intracellular bacterium that causes chronic infection in animals and humans. As with other intracellular pathogens, cell mediated immune responses (CMI) are crucial in affording protection against brucellosis. B. abortus strain RB51 has been shown to be useful in eliciting protective CMI and antibody responses against Brucella in cattle and other animal species. Since the protective antigen (PA) of B. anthracis is known to induce antibodies, the pag gene encoding PA was expressed in B. abortus RB51, producing a dual vaccine to protect against both brucellosis and anthrax. In a previous study, the entire pag gene was expressed in strain RB51 and following immunization the vaccine induced antibodies against PA in A/J mice. However, PA stability and protective efficacy were less than desirable as only 1/6 were protected. The studies in this dissertation involved synthesizing a gene corresponding to domain 4 (PA4) of the pag gene utilizing the native codon usage of Brucella. The PA4 domain was fused to Brucella signal sequences of Brucella 18kDa protein, superoxide dismutase or no signal sequence to localize the PA4 to the outside cell envelope, periplasmic space or cytosol respectively. Comparisons of the expression level and stability of the native and synthetic PA4 in B. abortus strain RB51 were assessed by immunoblot. The protective efficacy of PA4 expressed in Brucella was assessed by immunization and protection studies in A/J mice against a live challenge with either B. abortus or B. anthracis Sterne spores. ELISA and western blot indicate the induction of PA specific antibodies by these recombinant strain RB51 vaccine constructs. Results based on subisotype antibody ELISA (IgG, IgG1, IgG2a and IgM) and CMI assays (cytokine ELISA of IL-4 and INF-g, and LPA) suggest a Th1 based immune response to strain RB51 and PA. B. abortus strain RB51 expressing PA4 fused to the signal sequence of Brucella 18kDa protein was able to induce 50% protection, while strain RB51 expressing PA4 with no signal sequence gave 17% protection against B. anthracis Stern spore challenge. Mice were boosted with an intraperitoneal injection of purified PA after an initial immunization with Brucella vaccine candidates, sterile saline or pure PA. Protection assessed by live challenge with B. anthracis Sterne spores increased following boosting with PA in 4 cases. Immunization with purified PA, and 3 strain RB51/PA vaccines and a PA boost gave protection against a spore challenge ranging from partial to full. This study suggests that additional work is needed to define the antigens of B. anthracis involved in the induction of specific CMI. Ph. D.

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Bagchi, Tamishraha. "Immune mechanisms in murine brucellosis : studies with strain RB51, a rough mutant of Brucella abortus /." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-09162005-115020/.

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Barbknecht, Andrea Ellen. "Ecology of elk parturition across winter feeding opportunities in the brucellosis endemic area of Wyoming." [Ames, Iowa : Iowa State University], 2008.

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Shirima, Gabriel Mkilema. "The epidemiology of brucellosis in animals and humans in Arusha and Manyara regions in Tanzania." Thesis, University of Glasgow, 2005. http://theses.gla.ac.uk/4826/.

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The aims of this study were to assess community knowledge, awareness and practices on zoonoses, to gather baseline data on brucellosis in livestock and wildlife, to establish brucellosis seroprevalence in domestic ruminants and humans and risk factors associated with livestock seropositivity, to assess brucellosis dynamics and impact on livestock production and reproduction and to evaluate the performance of the Rose Bengal Plate Test (RBPT) in Tanzania. The results described in this study were carried out through Participatory Rural Appraisal (PRA), cross-sectional and longitudinal studies. In the PRA and cross-sectional studies, rabies, tuberculosis, anthrax and brucellosis were the zoonoses most frequently identified. Cattle were frequently identified as being associated with tuberculosis, anthrax and brucellosis, whereas dogs were frequently identified as being associated with rabies. Small ruminants, pigs, cats and poultry were either infrequently, or not identified as being associated with zoonoses. Recognition of clinical signs of zoonoses in humans was better than in animals. Ingestion of animal products was a route frequently identified as transmitting zoonoses to humans. During the baseline serosurvey, seroprevalences for brucellosis were 6.2% in cattle, 6.5% in small ruminants and 13% in wildlife, respectively. Seropositivity was significantly higher in the pastoral (13.2%), followed by agro-pastoral (5.3%), and lowest in the small holder dairy system (2.3%) (p<O.05). During the cross-sectional serosurvey, the seroprevalence was significantly higher in older animals and large herds (p<O.OOl). Variation in seropositivity between households was higher (1-30%) in the pastoral compared to agro-pastoral (1-14%) households. The model that best explained c-ELISA seropositivity included the feeding of dogs with foetuses and placentae, calving during the wet season, and the fanning system. In humans, 28% of families were seropositive for brucellosis with the highest levels in Ngorongoro district (46%), and lowest in Babati district (0%). Families with seropositive herds were 3.3 times more likely to be seropositive. However, 25% of families were seronegative when their herds were seropositive, and 48% of families were seropositive with seronegative herds. In the longitudinal study, the incidence was 73211,000 cases per animal-years at risk with an estimated survival probability of 0.836. Households with a high seroprevalence at the initial sampling had a high incidence of seroconversion in the subsequent visits. Occurrence of new seropositive cases was significantly higher in the wet season (p< 0.05). Calf serostatus was statistically associated with dam serostatus but no significant difference in growth rate was observed between calves suckled from seropositive and seronegative dams. Brucella melitensis type-1 was isolated from goats' milk following culture. Blood and placenta samples were negative on bacteriological culture. The RBPT was found to have low sensitivity in both field and laboratory settings. Brucellosis infection in livestock is widespread, but poses the greatest risk to human health and livestock production in pastoral systems in Tanzania.

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Lambert, Sébastien. "Transmission and management of brucellosis in a heterogeneous wild population of Alpine ibex (Capra ibex)." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1278.

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La gestion des maladies infectieuses dans la faune sauvage se heurte à de nombreuses limites, et le développement de stratégies efficaces représente un défi de taille. Pour atteindre cet objectif, une compréhension fine des facteurs influençant la transmission et la persistance de l’infection est nécessaire. Parmi ces facteurs, l’hétérogénéité de transmission est une caractéristique importante des populations sauvages. En effet, la diversité des comportements, des structures sociales et spatiales, ou encore des espèces peut conduire à des contributions très variables au nombre de nouvelles infections. Par conséquent, quantifier l’hétérogénéité de transmission pourrait permettre d’améliorer l’efficacité des mesures de gestion sanitaire dans la faune sauvage, en ciblant les individus ou les unités de population qui sont responsables de la majorité des évènements de transmission. L’objectif de cette thèse était d’améliorer les connaissances sur la gestion des maladies infectieuses dans des populations sauvages hétérogènes, en utilisant la brucellose à Brucella melitensis dans une population de bouquetin des Alpes (Capra ibex) comme modèle d’étude. En effet, la biologie de la brucellose et l’écologie de l’espèce hôte se prêtent bien à l’existence et donc à l’étude d’une hétérogénéité de transmission à différentes échelles. A l’aide de cultures bactériennes, nous avons tout d’abord montré que seulement 58 % des individus séropositifs sont à risque d’excréter la brucellose, et que ce risque diminue avec l’âge. Ensuite, mettant à profit l’existence d’informations détaillées sur la dynamique de population et le comportement du bouquetin, et de données épidémiologiques dans la population d’étude, nous avons développé un modèle individu-centré afin de quantifier l’hétérogénéité individuelle et spatiale de la transmission. Nous avons démontré que la transmission de la brucellose était hétérogène entre individus, les femelles provoquant environ 90% des nouvelles infections, et entre unités spatiales, plus de 80% des cas de transmission ayant lieu dans les trois sous-unités socio-spatiales qui forment la zone cœur du massif. Nous avons également estimé l’évolution temporelle de la séroprévalence et de la force d’infection, en utilisant différents modèles statistiques. Les résultats suggèrent que l’importante opération de capture menée en 2015, avec test systématique et élimination des individus séropositifs, a permis de diminuer la transmission de la brucellose dans la population. Sur la base de l’ensemble de ces résultats, nous avons évalués une série de stratégies de gestion sanitaire qui pourraient être utilisées à l’avenir dans la population. Les résultats, issus du modèle individu-centré, confirment que la stratégie prioritaire devrait être d’éliminer le plus d’individus séropositifs, et que cibler les femelles et/ou la zone cœur permet d’améliorer l’efficacité des mesures. Bien qu’il n’y ait pas de solution évidente pour la gestion de la brucellose dans notre cas d’étude, les stratégies de gestion ciblées sont très prometteuses et permettent de raffiner les mesures sanitaires classiquement utilisées. Il est donc primordial de bien comprendre l’hétérogénéité de transmission dans les populations sauvages infectées, et de rechercher des stratégies ciblées qui peuvent permettre d’améliorer la gestion en termes d’efficacité et d’acceptabilité The management of infectious diseases in wildlife reservoirs is particularly challenging and faces several limitations. The development of appropriate management strategies requires a detailed understanding of the factors affecting the transmission and persistence of the infectious agent in the population. Among these factors, heterogeneity of transmission is a common characteristic in natural host-pathogen systems. Indeed, wild animals express a broad range of behaviours, are organised in a variety of social and spatial structures, occupy many areas with very different characteristics and belong to a large diversity of species. Such heterogeneities, from between-individuals to between-species, may result in different contributions to the overall number of new cases of infections. Thus, understanding transmission heterogeneity could provide valuable insights on how to effectively manage these systems, by targeting the individuals or areas that are responsible for most transmissions. The aim of this thesis was to provide insights on the monitoring and management of infectious diseases in heterogeneous wild populations, using Brucella melitensis infection in a French population of wild Alpine ibex (Capra ibex) as a case study. The biology of brucellosis and the ecology of Alpine ibex makes this case study a good candidate for transmission heterogeneity at several levels. Using bacterial examinations, we first established that only 58% of seropositive individuals were at risk to excrete Brucella, and that this risk decreased with increasing age. Then, we took advantage of detailed information available on ibex population dynamics, behaviour, and habitat use, and on epidemiological surveys, to build an individual-based model in order to quantify heterogeneity at the individual and spatial levels. The transmission is extremely heterogeneous between individuals, with females generating around 90% of the new cases of brucellosis infection, and between spatial units, three of the five socio-spatial units (the core area) accounting for more than 80% of brucellosis transmission. Using statistical models to estimate the temporal dynamics of the seroprevalence and of the force of infection in the population, we found evidence that the massive captures with test-and-remove operations that were conducted in 2015 managed to reduce brucellosis transmission in the population. Based on these results, we evaluated several predictive disease management strategies in the individual-based model. Our results confirmed that the primary strategy should be to remove as many seropositive individuals as possible, and that strategies targeting females and/or the core area are more effective than untargeted management. Although there is no silver bullet for the management of brucellosis in the population of study, targeted strategies offer a wide range of promising refinements to classical sanitary measures. We therefore encourage to look for heterogeneity in other infection-wildlife systems and to evaluate potential targeted strategies for improving management schemes in terms of efficiency and acceptability

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Silva, Nairleia dos Santos. "Estudo das vacinas contra brucelose bovina: revisão." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-01072013-170508/.

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A brucelose bovina é uma das zoonoses mais difundidas no mundo e provoca prejuízos econômicos decorrentes de problemas reprodutivos. Diversos investimentos e esforços têm sido feitos para preveni-la em várias partes do mundo. Em destaque no cenário da pesquisa mundial sobre brucelose, está a busca por uma vacina que seja inócua aos humanos e animais, garanta uma boa imunidade e, principalmente não interfira nos testes de diagnóstico. Desde a criação da primeira vacina contra brucelose, diversas outras foram desenvolvidas, no entanto, poucas foram aceitas e usadas em larga escala. As perspectivas para o futuro das vacinas contra brucelose, demostram ser tão variadas quanto o seu passado. Nesse contexto, o objetivo desse trabalho é fazer uma reflexão sobre as vacinas contra brucelose considerando as principais vacinas desenvolvidas no passado, as utilizadas na atualidade e as perspectivas para a vacinologia contra brucelose. Bovine brucellosis is one of the most widespread zoonoses in the world and it causes economical losses due to reproductive problems. Several investiments and efforts have been done to prevent bovine brucellosis in many parts of the world. The search for a vaccine which is harmless to both human and animals, ensure good immunity and , mainly, does not interfere in diagnostic tests is featured on the scene of worldwide research on brucellosis. Since the creation of the first vaccine against brucellosis, several others have been created. However, few have been accepted and widely used. The perspectives for the future of vaccines against brucellosis can be seen as varied as they were in the past. In this context, the aim of this study is to reflect on brucellosis vaccines considering the main vaccines developed in the past, the ones in use today and the perspectives for the future of vaccinology againt brucellosis.

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Nyanhongo, Nhamo. "Field trial to evaluate the brucellin skin test in cattle in the Mpumalanga Province, South Africa." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/33370.

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Brucellosis is a disease of socio-economic and zoonotic importance worldwide. In animals it is associated with the ingestion of feed that is contaminated with cyetic material from aborting herd-mates, while in humans it is associated with the consumption of unpasteurised milk and dairy products from infected animals. It may also be acquired from contact with infected material of animal origin by farmers, veterinarians, and abattoir and laboratory workers. Brucellosis was first reported in South Africa in the late nineteenth century. It is still present in the country today, with reported annual losses of at least R 300 million, and a national annual incidence of 5 000 cases in humans. The global incidence of human brucellosis is about half a million infections annually. As the incidence of human brucellosis is directly associated with prevalence in animals, control of animal brucellosis is emphasised. Veterinary control is compromised by the chronic nature and the variable incubation period of the disease, with an estimated up to 15% of cattle in infected herds aborting before sero-conversion. Latency, which involves about 5% of calves born from infected dams, is also problematic as these infected animals often test seronegative, only to seroconvert in the peri-parturient period, thus allowing opportunity for disease spread within and between herds before diagnosis is made. In addition, the currently used serological tests are at times unable to distinguish brucellosis from cross-reacting antibodies from other infections or brucellosis vaccines. x It was the objective of this study to investigate, under South African conditions, the value of the brucellin skin test (BST) in improving the sensitivity and specificity of the currently used serological tests. It has proved a valuable additional test in diagnosing early and latent infections as well as in differentiating brucellosis from cross-reacting organisms in unvaccinated cattle in Europe. The study also evaluated the benefit of replacing some of the currently used serological assays with the fluorescence polarisation assay (FPA). The FPA, a rapid and homogenous serological test with only a few operational steps, has been validated and is in current use in Canada. The study was carried out in Mpumalanga Province, on herds selected to reflect prevailing South African farming conditions. These herds were divided into certified Brucella abortus-negative herds (608 head) for the estimation of BST specificity, and confirmed B. abortus-infected herds (845 head) for the estimation of BST sensitivity. The results obtained indicated the BST had a specificity of 99.18%, and a relative sensitivity of 42.86%. However, 65.38% of BST-positive animals were negative on serology. When the high specificity is considered, together with the experiences of other researchers who found that the skin test became positive earlier than serological tests, these animals may be assumed infected. It is concluded that the BST is a valuable addition to the panel of diagnostic tests currently used to identify infected herds and individuals in South Africa. The FPA, with a relative sensitivity of 93.65% and a specificity of 98.85%, can potentially be of use as a screening test under South African conditions. Dissertation (MSc)--University of Pretoria, 2012. gm2014 Veterinary Tropical Diseases unrestricted

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Mohamed, Gamal Wareth Abdelaziz [Verfasser]. "Molecular Epidemiology of Brucellosis in Egypt, Diagnostic Procedures, Proteomics and Pathogenesis Studies / Gamal Wareth Abdelaziz Mohamed." Berlin : Freie Universität Berlin, 2015. http://d-nb.info/1077212003/34.

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Cassidy, Clifton Clark. "Brucella abortus Strain RB51 Outer Membrane Vesicles as a Vaccine Against Brucellosis in a Murine Model." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/33859.

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Brucella abortus is a zoonotic agent that primarily infects cattle and causes brucellosis. B. abortus strain RB51 is a live, attenuated vaccine licensed for cattle. However, there is no available vaccine to prevent human brucellosis. Outer membrane vesicles have been tested as potential vaccines to prevent diseases caused by bacterial species. OMV are constantly released from Gram-negative bacteria. They are comprised principally of the outer membrane components and periplasmic proteins from the bacterial cell envelope. The research in this thesis examined the adjuvant property of non-replicative, metabolically active irradiated strain RB51 and the protective ability of OMV derived from strain RB51. Irradiated B. abortus strain RB51 was assessed for its ability to act as an adjuvant to induce protection against malaria. It was found that irradiated B. abortus strain RB51 administered along with fasciclin related adhesive protein (FRAP) to mice induced a protective immune response and a significant decrease in parasitemia after challenge with Plasmodium berghei. Strain RB51 and strain RB51 over-producing Cu/Zn superoxide dismutase (Cu/Zn SOD) were used to produce OMV. Western blotting and SDS-PAGE gel staining confirmed the presence of OMV and the over-production of Cu/Zn SOD. OMV were delivered to mice using an intraperitoneal route and, in some cases, with aluminum hydroxide adjuvant. The immune response was assessed by antibody isotyping with respect to OMV and measuring splenic clearance (i.e. protection) from a B. abortus strain 2308 challenge. The results demonstrate that OMV from B. abortus strain RB51 or strain RB51 over producing Cu/Zn SOD produced a Th1 polarized immune response as measured by specific OMV antibodies and cytokines but no statistically significant protection was observed. Master of Science

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Patrek, Victoria Elizabeth. "The effects of supplemental feeding on stress hormone concentrations in elk." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2009/patrek/PatrekV0509.pdf.

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On twenty-two feedgrounds in western Wyoming, elk (Cervus elaphus) are provided with supplemental feed throughout the winter. Brucellosis seroprevalence of feedground elk is 26% whereas other elk in the Greater Yellowstone Ecosystem have historically had a brucellosis seroprevalence of 2-3%. The aggregation of elk during peak transmission allows brucellosis to persist in the feedground populations. In addition to creating the opportunity for disease transmission, the aggregation of elk on feedgrounds may have detrimental physiological effects. Studies have shown that chronically high stress hormone concentrations can suppress the immune system and lead to increased disease susceptibility. Potential stressors on the feedgrounds include high densities, large group sizes and aggressive social interactions. In this study I investigated how factors associated with supplemental feeding affect stress hormone levels, as indexed by fecal glucocorticoid levels, in elk on feedgrounds and elk on native winter range. I also worked with managers to experimentally alter the feeding distribution on the feedgrounds to examine how feeding density affects stress hormone levels and aggression rates. Results show that elk on feedgrounds have stress hormone levels 31% higher than elk on native winter range (Welch's tâ‚‚â‚‡.â‚‚â‚ƒ=2.39, p=0.024). Experimental reduction of feed density did not have an effect on stress hormone level or aggression rates. But note the relationship between fGCs and local densities here. Although the feeding treatments did appear to reduce local feeding densities,s this effect was not significant and was small relative to the large differences in density among sites. Regardless as to the cause of the high stress hormone levels seen in supplementally fed elk, the feedgrounds are creating an epidemiological setting for disease transmission and a physiological state that may increase susceptibility to disease. The impact of these stress hormone concentrations on disease susceptibility remains unknown, but may be an important driver of disease dynamics in these elk populations.

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Makita, Kohei. "Urban and peri-urban agriculture and its zoonotic risks in Kampala, Uganda." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4924.

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In developing countries, cities are rapidly expanding, and urban and peri-urban agriculture (UPA) has an important role in feeding a growing urban population. However, UPA carries risks of zoonotic disease transmission. This study aims to understand the characteristics of UPA in Kampala, Uganda and the zoonotic risks to humans. Following a general overview of the subject in Chapter 1, Chapter 2 describes the determination of urban, peri-urban and rural areas of the Kampala economic zone and socio-economical characteristics of the peri-urban interface compared with the urban and rural counter parts using the Village Characteristic Survey in 87 randomly selected Local Councils (LC1s). Chapter 3 describes the characteristics of UPA in Kampala and found both the contribution of agriculture to the livelihood and risks of zoonoses were high. In Chapter 4, the most important zoonotic diseases affecting populations living in urban and peri-urban areas in Kampala were identified; brucellosis, GI infections, Mycobacterium bovis tuberculosis and Taenia solium cycticercosis based on investigations using the medical records of Mulago National Referral Hospital. Chapter 5 describes a series of case-control studies of the identified most important zoonoses using a spatial approach. The risks of identified zoonoses might be homogenously high at all levels of urbanicity. Brucellosis appeared to be the most significant disease. Chapter 6 investigates brucellosis further, with an epidemiological investigation into the prevalence of the disease in milking cows and a quantitative analysis of the level of infection in milk for sale in and around Kampala. The prevalence was 6.2% (95%CI: 2.7-9.8) at the herd level. Chapter 7 describes the risk analysis for purchase raw milk infected with Brucella abortus in urban areas of Kampala. A quantitative milk distribution model was developed synthesizing the results from the cattle survey and interviews with milk sellers. The infection rates of milk at sale obtained from milk testing and cattle survey were multiplied to this model to present distribution of the risk. 11.7% of total milk consumed in urban Kampala was infected when purchased and the risk management analysis found the most effective control option for human brucellosis was construction of milk boiling centres either in Mbarara, the largest dairy production area in Uganda, or in peri-urban areas of Kampala.

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Suxo, Blanco Macario. "Brucellosis in alpacas (Lama pacos) in communities of the city Ulla Ulla, Franz Tomayo province, department of La Paz." BYU ScholarsArchive, 2005. https://scholarsarchive.byu.edu/etd/5436.

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This investigation was performed in the Altiplano Altoandino sub-humid region in the Ulla Ulla district, Pelechuco township, Franz Tomayo province, department of La Paz, Bolivia. The objective of this study was to quantify and compare the presence of Brucellosis in male and female alpacas (Lama pacos) at ages 2, 3, 4, 5, 6, and 7 years. Blood samples were taken from the jugular vein of 500 alpacas from the Hichucollo, Huacuchani, Ucha Ucha, and Ulla Ulla communities. The serum from each sample was separated and a serological diagnosis was performed by rapid agglutination with Rose Bengal chemical stain. In the Ulla Ulla district, 11.0% of alpacas were suspected of being infected. Of that 11.0%, 9.6% represented female alpacas while the remaining 1.4% represented male alpacas. By community, the overall results were 0.6%, 0.2%, 7.4%, and 2.8% for Hichucollo, Huacuchani, Ucha Ucha, and Ulla Ulla respectively. With regards to gender in each community, 1.4%, 1.6%, 13.3%, and 11.1% of female alpacas and 2.7%, 0.0%, 1.2%, and 1.9 % of male alpacas were suspected of being infected in Hichucollo, Huacuchani, Ucha Ucha, and Ulla Ulla, respectively. According to age, 0.8%, 2.6%, 3.8%, 2.0%, 11.8%, and 0.0% were suspected of Brucellosis in alpacas 2, 3, 4, 5, 6, and 7 years old, respectively in the Ulla Ulla district. The analysis of variance among the results does not present significant differences (p ≥ 0.05), failing to reject the given hypothesis. The final prevalence point found in the Ulla Ulla district was 11.0%. It was concluded that the prevalence of suspected cases of Brucellosis in alpacas is a consequence of the antigenic characteristics of each biotype. Furthermore, the results affirm that the poor management of livestock and livestock health lead to significant problems with alpaca health. It is therefore necessary to implement control strategies as well as disease monitoring in communities by following a detailed program of diagnostic tests for Brucellosis. Also, non-infected flocks must be protected against infection.

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Silva, Lilia Marcia Paulin. "Estudo comparativo de diferentes técnicas sorológicas para diagnóstico de infecções por Brucella abortus em búfalos (Bubalus bubalis)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-25092007-101838/.

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Tendo em vista a importância da bubalinocultura como fonte de proteína para o Brasil e também do Programa Nacional de Controle e Erradicação da Brucelose e da Tuberculose para a evolução das cadeias produtoras de bovinos e bubalinos e, devido à escassez de estudos sobre o sorodiagnóstico da brucelose na espécie bubalina, procedimento no qual se apóia o processo de certificação de rebanhos livres e monitorados, o presente estudo objetivou comparar o desempenho de diferentes testes para o sorodiagnóstico da brucelose nessa espécie. Soros de 696 fêmeas bubalinas adultas foram submetidos aos testes qualitativos BPA, AATE, AAT e quantitativos: SRP, SLT, ELISAI, ELISAC, PF e ME e FC. Foi empregada, gold standard, a combinação de dois testes, FC e ME, considerando dois critérios: a) animais positivos para os reagentes na FC (título ≥ 20UI) e no ME (critério para fêmea vacinada) e como negativos os animais não reagentes na FC (título < 20UI) e no ME; b) animais positivos os reagentes na FC (título ≥ =20UI) e no ME (critério para fêmea não vacinada) e negativos os não reagentes na FC (título < 20UI) e no ME. Esta consideração foi necessária em função dos animais não apresentarem histórico de vacinação confiável o que interfere na determinação do ponto de corte a ser utilizado no teste ME de animais vacinados e não vacinados. Desta forma, numa primeira análise todos os animais foram avaliados no ME como vacinados e em outra como não vacinados. Com base nesses resultados, foi construída a curva ROC para todos os testes quantitativos (SRP, SLT, ELISAC, ELISAI e PF). Com os resultados dessa análise estabeleceu-se pontos de corte que otimizam os valores de sensibilidade e especificidade relativas para cada teste. Esses valores foram utilizados para o cálculo do índice de concordância Kappa para cada teste, incluindo os qualitativos. Concluiu-se que: a) os resultados dos estudos com os testes de ELISAC e PF em bovinos podem ser inferidos para bubalinos com razoável segurança; b) devem ser estabelecidos pontos de corte específicos para búfalos para o SLT, o SRP e o ELISAI; c) as melhores combinações de sensibilidade e especificidade relativas foram alcançadas pelo ELISAC, o PF, o BPA e o AAT; d) os melhores resultados de Kappa foram verificados para o ELISAC (kappa), PF, BPA, AATE e AAT; e) o BPA, AAT e AATE são os melhores testes para o sorodiagnóstico de triagem em bubalinos e o ELISAC e o PF são os mais promissores testes confirmatórios nessa espécie, já que ganhos adicionais de especificidade podem ser alcançados pelo aumento do ponto de corte. Considering the importance of the buffalo as a protein source in Brazil and the National Program of Brucelosis and Tuberculosis Control and Eradication for the evolution of the bovine and bubaline sector, and also due to the few number of studies on serological diagnosis of brucelosis in this specie, procedure that supports the process of certification of brucelosis free herds, the present study aimed to compare different serological tests for brucelosis diagnosis on buffaloes. Serum samples from 696 adult bubaline females had been analyzed to BPA, AATE, AAT (qualitatives), SRP, SLT, ELISAI, ELISAC, PF and ME and FC (quantitatives). The combination of two tests, FC and ME was used as reference, considering two criteria: a) positive animals: reactors for the FC (titer ≥ 20UI) and ME (vaccinated females), negative animals: no reactors for the FC (titer < 20UI) and ME (vaccinated females); b) positive animals: reactors for the FC (titer ≥ 20UI) and ME (not vaccinated females), negative animals: no reactors for the FC (titer < 20UI) and ME (not vaccinated females). It was necessary because was not possible to garantee the true vaccination status of the animals. The first step was performing the ROC analysis for all the quantitative tests (SRP, SLT, ELISAC, ELISAI and PF), and so the relative sensitivity and specificity and the Kappa were calculated for each test. Conclusions: a) the cut offs of ELISAC and PF tests proposed for bovines can be used for bubalines with reasonable security; b) specific cut offs for buffaloes to be used in SLT, SRP and ELISAI must be established; c) the best relative sensitivity and specificity had been reached by the ELISAC, PF, BPA and AAT; d) the best results of the Kappa had been reached by ELISAC (kappa), PF, BPA, AATE and AAT; e) BPA, AAT and AATE are the best screening diagnosis test for bubalines and ELISAC and PF are the most promising confirmatory tests for this species.

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Colby, Lesley A. "The Humoral Immune Response of Elks (Cervus elaphus nelsoni) and Mice to Vaccination with Brucella abortus Strain RB51." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/30600.

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Vaccine Brucella abortus strain RB51, unlike the wild strain 2308 and another vaccine strain (strain 19) does not induce anti-O-chain antibodies. An efficacious vaccine strain that fails to produce an O-chain and thus a lack of an anti-O-chain humoral response greatly simplifies identification of vaccinated versus field strain infected animals. The three primary objectives of this research were the following: 1) to develop a serological assay to detect anti-RB51 antibodies in vaccinated elk (Cervus elaphus nelsoni), 2) to identify potential antigenic alterations in RB51 after vaccination of elk and BALB/c mice, and 3) to confirm the general stability of RB51. Elk were divided into four groups based upon gender and the route of inoculation (subcutaneous or ballistic) of RB51 bacteria. This study developed a highly reliable ELISA (using a monoclonal anti-bovine IgG 1 antibody and acetone killed whole RB51 bacteria) which can identify RB51-vaccinated elk. Also, isolates recovered from RB51-vaccinated elk were inoculated into female BALB/c mice whose spleens were then cultured. All elk and mice isolates were bacteriologically, biochemically, and serologically evaluated. This study showed that RB51 is a highly stable strain, which does not revert to smooth morphology or initiate synthesis of LPS-O-chain, maintains it biochemical characteristics, does not undergo detectable antigenic variations, and remains attenuated even after successive passages in elk and mice. Overall, this research indicates that RB51 is a vaccine candidate for the prevention of brucellosis in elk. Further studies are needed to determine the protective capabilities of RB51 in elk. Master of Science

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Almeida, Laerte Pereira de. "Bursite cervical em bovinos: avaliação da brucelose como fator de risco." Universidade de São Paulo, 1996. http://www.teses.usp.br/teses/disponiveis/6/6135/tde-06022018-140305/.

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Estudo realizado no Frigorífico Triângulo de Uberlândia, Minas Gerais (MG), utilizando delineamento tipo caso-controle, procurou estabelecer a possível relação entre bursite cervical e brucelose, em bovinos abatidos no período de agosto de 1993 a julho de 1994. O diagnóstico de brucelose foi realizado mediante a prova de soroaglutinação rápida em placa. Os casos de bursite foram identificados, por técnico do Serviço de Inspeção Federal (SIF), com base em características morfológicas, previamente padronizadas. Para a determinação do odds ratio e do risco atribuível , entre bursite e brucelose, utilizaram-se 30 animais com o quadro e, como controle, 90 bovinos sem a patologia. Dos municípios que enviaram animais para o abate 60,0 por cento pertenciam à microregião do Triângulo Mineiro, MG, correspondendo a 94,7 por cento do total de bovinos abatidos; o número de machos e fêmeas equivaleram-se. A frequência de ocorrência de bursite cervical foi igual a 0,14 por cento (40/28.677); 80,0 por cento dos casos foram registrados entre os meses de agosto de 1993 e fevereiro de 1994. Goiás (GO) apresentou uma frequência de bursite da ordem de 0,28 por cento contra 0,13 por cento de MG (P=0,139) ; Itapirapuã, GO, com 5,0 por cento de casos de bursite, foi o município com a maior ocorrência da patologia (P<0,05). As fêmeas apresentaram 0,20 por cento de frequência de bursite, contra 0,07 por cento dos machos (P<0,05). Vascularização intensa (56,7 por cento ) e espessamento da parede da bolsa (43,4 por cento ) foram as características morfológicas mais encontradas. Dos animais com bursite, 13,3 por cento eram brucélicos, contra 5,6 por cento do grupo controle (P=0,115). Dentre aqueles com brucelose e bursite, as bolsas continham fibrina (40,0 por cento ) e projeções digitiformes (33,3 por cento ); encontradas as presenças de pús 1 de nódulos e de líquido viscoso. O odds ratio encontrado entre a brucelose e a bursite foi da ordem de 2,61 (P>0,05). O risco atribuível da patologia na população estudada foi igual a 7,64 por cento , valor esse correspondente à frequência esperada de redução de casos de bursite cervical, após a erradicação da brucelose em populações semelhantes à do presente estudo. No âmbito da saúde ocupacional, mesmo diante da ausência de relação estatística entre bursite e brucelose, esta patologia deve continuar a merecer a atenção de técnicos e profissionais de frigoríficos, com o escopo de diminuir eventuais riscos de infecção de trabalhadores, bem como de evitar a contaminação de carcaças, equipamentos e instalações. The present study was conducted in the municipal of the Municipality of Uberlândia in the State of Minas Gerais. An examination is made of the association between a sorological diagnosis indicating brucellosis and the existence of supraspinous bursitis in cattle slaughtered between August, 1993 and July, 1994. To diagnose brucelloses the \"Rapid Aglutination\" test was performed on a plate with the standardized antigen count considered to be positive if above 100. The bursas examined were identified by technicians of the Federal Inspection Service based on the presence of ten standardized morphological characteristics. Using the case-control design 30 animals identified as having supraspinous bursitis were compared with 90 animals rendomly selected, without bursitis- but with other characteristics (sex, background, lot, conformation) similar to those affected. All animals were then diagnosed for brucellos. Of all municipios counties that sent animals for slaught 60,0 per cent came from the microregion of Triângulo Mineiro, MG, corresponding to 94,7 per cent of the total of slaughtered bovine; the number of females and males were equivalent. 80,0 per cent of cases of bursitis were registrated between August 1993 and February 1994. The State of Goiás had a rate of 0,28 per cent of bursitis cases against 0,13 per cent in Minas Gerais, (P=0,139). Itapirapuã, GO, with 5,0 per cent of cases was the municipal region with the highest rate of ocorrence (P<0,05). The rate or bursitis in female animals was 0,20 per cent while in male it was 0,07 per cent (P<0,05). The most frequency intense vascularization (56,66 per cent ), the presence of nodules (53,33 per cent ). Of the animals with bursitis, 13,33 per cent were found to have brucellosis while of the other animals, 5,56 per cent had the disease (P=0,115). The morphological characteristics of the bursae examined of the animals with brucellosis contained, most frequency, fibrin (40,0 per cent ) and digital projections (33,3 per cent ). The presence of pus, nodules and viscous fluid were found only among the animals who tested negative for brucellosis. The odds ratio between brucellosis and supraspinous bursitis was 2,61 (P>0,05). The attributable risk of bursitis in the population was calculated at 7,64 per cent . This is to say that the expected frequency of supraspinous bursitis, with the eradication of brucellosis, can be expected to reduce by this amount (in populations similar to that of the present study) . In the area of work related health hazards, although the statistical relation between bursitis and brucellosis lacks significance, bursitis continues to merit the attention of technicians and profesionals employed in slaughterhouses in and effort to reduce the risk of infection to their health as well as contamination of carcasses, equipment and installations.

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Salgado, Vanessa Riesz. "Avaliacão das técnicas de cultivo microbiológico e soroaglutinação rápida em cartão com e se 2-Mercaptoetanol da Brucelose canina /." Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/94594.

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Orientador: Jane Megid Banca: Marcio Garcia Ribeiro Banca: Silvio Arruda Vasconcellos Resumo: A brucelose canina causada pela Brucella canis (B. canis) é uma das principais causas infecciosas de desordens reprodutivas em cães. O presente trabalho teve como objetivo comparar as técnicas de Cultivo Microbiológico e Soroaglutinação Rápida em Cartão (SAR) com e sem o emprego de 2-Mercaptoetanol (2-ME) no diagnóstico da brucelose canina. Adicionalmente foram avaliados sangue, urina, swab vaginal, prepucial e sêmen como materiais a serem processados no diagnóstico microbiológico. Foram avaliados 236 cães quanto à infecção por B. canis, muitos com histórico de problemas reprodutivos, dos quais 24,2% resultaram positivos na SAR, 10,2% na SAR-2ME, 28% na hemocultura, 9,2% na urocultura, 2,1% na cultura de swab vaginal, 13,6% na cultura dos swabs prepuciais e 28,6% no cultivo de sêmen. Dos 71 animais positivos no cultivo microbiológico, 92,9% apresentaram-se positivos na hemocultura. Nos demais materiais foram obtidos percentuais menores. A sensibilidade relativa da SAR resultou em 66,2% e a especificidade relativa 93,9%. A SAR-2ME apresentou sensibilidade relativa de 29,5% com ligeiro aumento na especificidade relativa 98,2%. Quando associados SAR e hemocultura foram observados 97,6% e 93,9% de sensibilidade e especificidade, respectivamente. Os resultados sugerem a utilização associada da SAR à hemocultura sem realização em paralelo com 2-ME. Abstract: Canine brucellosis caused by Brucella canis (B. canis) is one of the major infectious causes of reproductive disorders in dogs. The present study aimed to compare the performance of bacteriological methods and Rapid Slide Agglutination Test (RSAT) with or without 2-Mercaptoethanol (2-ME) in canine brucellosis diagnosis. Additionally, blood, urine, vaginal and prepucial swabs and semen were evaluated regarding their use in bacteriological diagnostic. Two hundred thirty six dogs, many of them showing reproductive problems, were submitted to investigation for diagnosis of B. canis infection. Among them, 24.2% were positive in RSAT, 10.2% 2ME-RSAT, 28% blood culture, 9.2% urine culture, 2.1% vaginal swab culture, 13.6% prepucial swab culture and 28.6% semen culture. Among the 71 positive dogs in bacteriological culture, 92.9% were positive in blood culture. The percentage of positivity was variable in others samples. The relative sensitivity of RSAT was 66.2% and the relative specificity was 93.9%. The 2ME-RSAT presented lower sensitivity 29.5% and greater specificity 98.2%. The use of blood culture and RSAT associated presented 97.6% e 93.9% of sensibility and specificity, respectively. These results suggest that RSAT should be used with blood cultures independently of the use of 2ME-RSAT. Mestre

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44

Tobias, Lynette. "The pregnant mouse model of brucellosis: the pathology and protection studies comparing Brucella abortus strains 2308, 19 and RB51." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/39917.

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45

Nyarku, Rejoice E. "Development and analytical validation of a genus-specific Brucella real-time PCR assay targeting the 16S-23S rDNA internal transcribed spacer." Diss., University of Pretoria, 2020. http://hdl.handle.net/2263/77428.

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Brucellosis is an economically important bacterial disease of both animals and humans. In sub-Saharan Africa, the diagnosis of the disease remains a challenge. Brucellosis is underreported in South Africa, due to inconsistency in reports of bacteriological and serological tests, which lack adequate sensitivity and specificity in the diagnosis of the disease. They also are ineffective in confirming brucellosis during early stages of the disease. The aim of this study was to develop a 16S-23S ribosomal deoxyribonucleic acid (rDNA) internal transcribed spacer (ITS) quantitative polymerase chain reaction (qPCR) assay for early diagnosis of brucellosis and as a rapid screening tool. To achieve this, blood, milk and tissue samples were spiked with B. abortus biovar (bv.) 1 (B01988-18 strain) to determine the analytical sensitivity and specificity of the assay. The efficiency was 105% in tissue, 99% in blood, and 93% in milk. The 95% limit of detection (LOD) of the ITS qPCR assay was highest in tissue, followed by blood, then milk; thus (1.45, 13.30 and 45.54 bacterial genome copies/PCR reaction). Furthermore, the diagnostic performance of the assay was compared to the Brucella cell surface protein real time polymerase chain reaction (BCSP31 qPCR) assay. Out of 56 aborted foetal tissue samples from bovine, ovine and caprine, 33% (19/56) were positive for Brucella spp. The sensitivity and specificity of the ITS qPCR assay were 87% and 95% respectively, compared to the 92% and 89% for the BCSP31 qPCR assay and 47% and 55% for bacterial culture, respectively. The ITS qPCR gave earlier CT’s with a difference in CT (ΔCT) between ITS and BCSP31 ranging between 7.1 and 3.24. The assay was efficient, sensitive and specific. It detected as little as 1.45 bacterial genome copies/PCR reaction in tissue, making this assay a valuable tool in early detection of the presence of the Brucella pathogen. It is sensitive and specific in the diagnosis of brucellosis. Dissertation (MSc)--University of Pretoria, 2019. Veterinary Tropical Diseases MSc Unrestricted

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McGiven, John. "Immunoselection and structural evaluation of Brucella O-polysaccharide epitopes and their application to the serodiagnosis of bovine brucellosis." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/45541.

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Brucellosis is one of the world’s most significant zoonosis and is caused by infection with members of the genus Brucella. These have a cell wall characteristic of Gram-negative bacteria including lipopolysaccharides and, in the most significant Brucella species, O-polysaccharide (OPS). The major economic and health impacts of the disease arise from livestock, in particular ruminants and swine, where the main clinical feature is reproductive failure. The principle source of infection in the general human population is most often via ingestion of unpasteurised dairy products. Serology is the most cost effective means of disease detection but has significant imperfections including false positive serological reactions (FPSRs) due to antibodies that are raised against other Gram-negative bacteria in possession of OPS structures similar to that of Brucella. Serology with non-OPS antigens has been largely ineffective and alternative approaches such as bacterial culture, PCR or measurements of cell mediated immunity are impractical, ineffective or unproven. The OPS from Brucella is an unbranched homopolymer of 4,6-dideoxy-4-formamido-D-mannopyranosyls (D-Rha4NFo) that are variably -(12) and -(13) linked. This structure contains some epitopes that are shared with the OPS from other organisms, notably Yersinia enterocolitica O:9, and some that appear to be unique. Previous attempts to harness the unique epitopes using competitive ELISA failed to resolve FPSRs because the unique and common epitopes overlap causing steric hindrance of specific antibody binding. Oligosaccharides were derived from the OPS of B. abortus, B. melitensis and Y. enterocolitica O:9 by partial acid hydrolysis. These were separated and analysed by chromatography with on-line ESI-QqToF and QqQ. OPS specific antibodies were used to select from this pool of oligosaccharides and those captured were evaluated by graphitised carbon chromatography with on-line ESI-QqQ. On the basis of the mass spectrometry evidence the synthesis of a D-Rha4NFo tetrasaccharide comprised of a single -(13) link flanked on either side by single -(12) links was commissioned. This tetrasaccharide was used to develop an indirect ELISA for the detection of specific antibodies. Equivalent indirect ELISAs were also developed using native OPS and from synthetic penta- and nonasaccharide antigens, received from a collaborating laboratory. The tetrasaccharide ELISA was the most effective assay for discriminating between bovine FPSRs and true positives. The diagnostic capability of this ELISA was significantly superior (P < 0.05) than all others except the pentasaccharide ELISA (P = 0.159). The results show that the iELISA developed with the tetrasaccharide may effectively detect antibodies from animals infected with Brucella strains with low or high abundance of -(13) links within their OPS and has a significantly improved capability to resolve FPSRs compared to antigens that include common OPS epitopes.

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Nombebe, Thobeka. "Prevalence, seasonal trends and incidences of cattle tuberculosis and brucellosis in the Cacadu municipality, Eastern Cape, South Africa." Thesis, University of Fort Hare, 2012. http://hdl.handle.net/10353/d1016200.

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A cross-sectional study was conducted from February 2011 to August 2012 to investigate the status and identify risk factors for Bovine Tuberculosis (BTB) and cattle Brucellosis. A total of 1277 cattle from 6 selected dairy farms were tested. The farms were purposively selected on suspected risk. Samples were analysed using Rose Bengal Test (RBPT) and Complement Fixation Test (CFT) for Brucellosis and Comparative Intradermal Tuberculin Test (CITT) for BTB. The results revealed the overall prevalence of 1.6% for Brucellosis and no BTB was found. Logistic regression analysis revealed that age of cattle, herd size and number of calves a cow has had significant association with Brucellosis with p-values 0.0071, 0.0490 and 0.000 respectively. The role of location (p>0.05), gender (p>0.05) and breed (p>0.05) in the occurrence of the disease was not statistically significant at α=0.05, although higher rates were obtained in females and Jersey breed. Questionnaires were also administered to 47 individuals a total of 12 females and 35 males. Most respondents were not aware about cattle brucellosis and cattle tuberculosis. Consumption of raw or unpasteurized milk still occurs with 74.75% of respondents revealed.

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Mai, H. M. (Hassan Mohammed). "Epidemiological studies of brucellosis, campylobacteriosis and trichomonosis, and other factors affecting calving rate in cattle herds in northern Nigeria." Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/30870.

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Abstract:

Livestock production, of which cattle production is a major component, plays a key role in the socio-economic development of Nigeria, with 70-80% of the nation’s population of over 150 million engaged in agriculture and the livestock industry as their major occupation. Cattle production provides essential food products – meat, milk, and other dairy products, animal power, fuel, transport and organic manure for arable farming. However, the productivity and reproductive performance of cattle in Nigeria is generally low due to many factors, including a number of infectious reproductive diseases resulting in decreased calving percentage, infertility, abortion and decreased milk production. Brucellosis is one of the most important reproductive diseases and widespread zoonosis in the world and previous studies have indicated an increase in its occurrence in cattle in Nigeria. In addition, bovine campylobacteriosis and trichomonosis are widespread diseases associated with bovine infertility worldwide. However, there is little recent or reliable information on the prevalence of these important diseases in Nigeria and their effect on reproductive performance. Most studies have used nonrepresentative samples, small sample sizes and relatively non-specific diagnostic tests. Few studies have been conducted on bovine campylobacteriosis and trichomonosis in Nigeria and none on the concurrence of brucellosis and campylobacteriosis. Therefore, a large crosssectional study covering Adamawa, Kaduna and Kano states of northern Nigeria was designed. A multistage random cluster sampling strategy was used to sample 4,745 cattle from 271 herds, including diverse production systems. The objectives of the study were to estimate, at the animal and herd level, the seroprevalence of brucellosis in adult cattle, the prevalence of bovine genital campylobacteriosis and trichomonosis in bulls and the association between the three diseases. In addition, the study aimed to identify herd-level managemental and environmental risk factors for each of the diseases, as well as risk factors for within-herd seroprevalence of brucellosis. Further objectives were to determine the reproductive efficiency and occurrence of reproductive disorders in the herds, and to estimate the effect of the three infectious diseases, as well as other factors, on calving rate. Serum samples were tested for antibodies to Brucella using the Rose-Bengal plateagglutination test (RBPT) and positives were confirmed using a competitive enzyme-linked immunosorbent assay (c-ELISA). Thirty-seven percent of all animals were RBPT positive, and after confirmation with c-ELISA the overall true animal-level prevalence, adjusted for test sensitivity and specificity and for sampling weights and clustering in the complex survey design, was 26.3% (95% CI, 22.1%-31.0%). Of the herds sampled, 210 (77.5%; 95% CI, 68.6%-84.5%) had at least one animal positive to both tests; this did not differ significantly between states (P = 0.538). A significantly higher seroprevalence of brucellosis was found in males than in females (P < 0.001), in non-pregnant than in pregnant females (P < 0.001), and in cattle >7 years than in cattle <4 years of age (P < 0.001). Seroprevalence was highest in the pastoral management system (45.1%) while the commercial system had the lowest seroprevalence with 15.9% (P < 0.001). Preputial samples of 602 bulls from 250 herds were tested for Campylobacter fetus and Tritrichomonas foetus using culture and identification. The estimated true animal-level prevalence of C. fetus infection in bulls was 16.4% (95% CI: 13.0%-20.7%), of which 18.5% was C. f. fetus and 81.5% was C. f. venerealis. Of the latter, 92% were C. f. venerealis biovar intermedius, the major aetiology of bovine genital campylobacteriosis. A higher prevalence was found in bulls >7 years old (33.4%) than in bulls 4-5 years old (13.6%) (P = 0.018). Prevalence was highest in the Gudali breed (28.8%) and in pastoral herds (43.5%). There was a strong positive association between the presence of campylobacteriosis and brucellosis, both within bulls (OR = 8.3, 95% CI: 5.2-13.4) and within herds (OR = 16, 95% CI: 3.8-68) (P < 0.0001). All the samples tested for trichomonosis using different isolation methods were negative. Multilevel logistic regression models were used to identify herd-level risk factors for brucellosis and campylobacteriosis. The odds of both Brucella seropositivity and C. fetus infection increased significantly with the presence of small ruminants (sheep and/or goats) on the same farm and with the introduction of animals to the farm without quarantine. In addition, Brucella seropositivity was positively associated with larger herd size, with the pastoral management system and with the presence of a crush or improvised chute on the farm, while regular or occasional gynaecological examination was associated with reduced odds of seropositivity. Initial purchase of stock from a market, regular or occasional gynaecological examination, failure to practice regular or occasional herd prophylactic measures and high rainfall were associated with increased odds of C. fetus infection. A zeroinflated Poisson model showed that the presence of small ruminants, the introduction of animals without quarantine, and borrowing or sharing of breeding bulls were associated with a higher within-herd seroprevalence of brucellosis within infected herds, while routine provision of mineral supplementation was associated with a lower within-herd seroprevalence. Thesis (PhD)--University of Pretoria, 2012. Production Animal Studies PhD Unrestricted

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49

Coker, Michelle. "Detection of an immunological response in heifers experimentally infected with epizootic bovine abortion (foothill abortion)." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1456474.

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50

Meirelles, Raphaella Barbosa [UNESP]. "Avaliação do teste do antígeno acidificado tamponado em soros tratados com rivanol como teste confirmatório no diagnóstico sorológico da brucelose bovina." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/94662.

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Abstract:

Made available in DSpace on 2014-06-11T19:27:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-15Bitstream added on 2014-06-13T20:56:04Z : No. of bitstreams: 1 meirelles_rb_me_jabo.pdf: 431142 bytes, checksum: 402455070a5e87681746e4ec463e7683 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) O trabalho teve por objetivo avaliar a prova do antígeno acidificado tamponado após tratamento dos soros com rivanol (AAT-RIV), como teste confirmatório no diagnóstico sorológico da brucelose bovina. Foram selecionadas 1.061 amostras de soros bovinos, previamente analisadas pelos testes preconizados pelo Programa Nacional de Controle e Erradicação de Brucelose Tuberculose (PNCEBT): como teste de triagem, a prova do antígeno acidificado tamponado (AAT), e como testes confirmatórios, a combinação das provas de soroaglutinação lenta e 2-mercaptoetanol (SAL+2-Me), e a reação de fixação de complemento (RFC). O AAT-RIV foi realizado com o antígeno nas concentrações de 8% e 4% de volume celular, não tendo sido encontrada diferença nos resultados. Os dados foram analisados pelo indicador kappa e pelo χ2 de McNemar, adotando-se com ponto-de-corte o título 25 no 2-Me e 4 na RFC. O AAT-RIV apresentou concordância regular (kappa = 0,53) com o AAT e boa com os testes confirmatórios (kappa: 2-Me = 0,67; SAL+2-Me = 0,66; RFC = 0,76). O χ2 de McNemar apontou diferenças significativas entre os testes. A comparação entre os resultados do AAT-RIV e a condição verdadeira do animal, estabelecida pela combinação dos resultados das provas AAT, SAL+2-Me e RFC, resultou em uma sensibilidade relativa de 76,5%, com intervalo de confiança (95%) de 72,7% a 80,3%, e especificidade relativa de 100%. Conclui-se que o AAT-RIV poderia ser utilizado como teste confirmatório no diagnóstico sorológico da brucelose bovina, sendo os animais com resultado positivo considerados infectados e aqueles com resultado negativo submetidos a um dos dois testes confirmatórios adotados pelo PNCEBT. The purpose of the investigation was to evaluate the rose Bengal plate test in bovine serum after treatment with rivanol (RBPT-RIV) as a confirmatory test for brucellosis diagnosis. Serum samples from 1,061 bovine were analyzed by serological diagnostic techniques adopted by the Brazilian Program for Animal Brucellosis and Tuberculosis Control and Eradication: as screening test, the rose Bengal plate test (RBPT), and as confirmatory tests, the 2- mercaptoethanol plus standard tube agglutination test (STAT+2-Me), and the complement fixation test (CFT). RBPT-RIV was performed with 8% and 4% cellular concentration antigen, and there was no difference between the results. Data were analyzed by kappa statistic and McNemar χ2 (2-Me cut-off = titer 25, and CFT cutoff = titer 4). RBPT-RIV showed a moderate agreement (kappa = 0,53) with RBPT, and substantial agreement with the confirmatory tests (kappa: 2-Me = 0,67; STAT+2-Me = 0,66; CFT = 0,76). The McNemar χ2 showed significant difference among the tests. Comparing the RBPT-RIV results with the true condition of the animals, stablished by combining the results of RBPT, STAT+2-Me and CFT, the relative sensitivity was 76.5%, with a 95% confidence interval from 72,7% to 80.3%, and relative specificity of 100%. The results suggested that the RPBT-RIV is suitable to be used as a confirmatory test for brucellosis serological diagnosis; in this case, an animal testing positive should be classified as infected, and an animal testing negative should be tested by CFT or STAT+2-Me.

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Dissertations / Theses on the topic 'Brucellosis Brucellosis Brucellosis Brucellosis'

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