Academic literature on the topic 'Leptospirosis/epidemiology'

The objective was to describe the current epidemiology and trends in New Zealand human leptospirosis, using descriptive epidemiology of laboratory surveillance and disease notification data, 1990–8. The annual incidence of human leptospirosis in New Zealand 1990–8 was 4·4 per 100000. Incidence was highest among meat processing workers (163·5/100000), livestock farm workers (91·7), and forestry-related workers (24·1). The most commonly detected serovars were Leptospira borgpetersenii serovar (sv.) hardjo (hardjobovis) (46·1%), L. interrogans sv. pomona (24·4%) and L. borgpetersenii sv. ballum (11·9%). The annual incidence of leptospirosis declined from 5·7/100000 in 1990–2 to 2·9/100000 in 1996–8. Incidence of L. borgpetersenii sv. hardjo and L. interrogans sv. pomona infection declined, while incidence of L. borgpetersenii sv. ballum infection increased. The incidence of human leptospirosis in New Zealand remains high for a temperate developed country. Increasing L. borgpetersenii sv. ballum case numbers suggest changing transmission patterns via direct or indirect exposure to contaminated surface water. Targeted and evaluated disease control programmes should be renewed.

Swine leptospirosis is an important bacterial disease known from the past century. At present its significance is underestimated contrary to the epidemiological and other scientific evidences. This review is dealing with aetiology, pathogenesis, epidemiology, clinical signs, post mortem findings, diagnosis, treatment and control measures of swine leptospirosis. Finally the relation of leptospirosis, in general, with public health is examined.

Background The burden of leptospirosis in sub-Saharan Africa remains unclear although it is accepted that this infection is widely spread in this region. The global estimated number of cases is one million with 58 900 deaths attributable to leptospirosis annually. Objective To describe the profile of patients with suspected leptospirosis and to compare their in hospital outcomes. Methods & Material We performed a retrospective study at a tertiary referral hospital in South Africa. All adults with suspected leptospirosis who had a laboratory request for leptospirosis ELISA IgM testing between 2005 and 2015 were included. Clinical and laboratory findings at presentation were correlated with the patient's subsequent clinical course and ELISA IgM status. Results During the study period 223 patients who had ELISA IgM test requests were enrolled. Leptospirosis ELISA IgM was positive in 45 (20%) patients. Enrolled patients had a median age of 38 (IQR 31 – 53) years, 147/223 (66%) were males and 80/223 (36%) were HIV positive. There were 12/45 (27%) HIV-positive patients in the IgM-positive group compared to 68/178 (38%) in the IgM-negative group, p=0.22. Compared to IgM-negative patients, patients with positive IgM were more likely to present with jaundice 37/45 (82%) vs. 82/178 (46%), p <0.01, and acute kidney injury (AKI) 34/45 (76%) vs.102/178(57%), p=0.06. The median length of hospital stay was 13 days (IQR 8-22 days) for IgM-positive compared to 10 days (IQR 6-21 days) in IgM-negative patients, p= 0.10. A total of 11/45 (24%) IgMpositive patients required ICU admission compared to 41/178 (23%) of IgM-negative patients, p=0.84 and the median length of ICU stay was 7 days (IQR 4-11) for IgM-positive compared to 6 days (IQR 3-9.5) for IgM-negative patients, p=0.51. There were 13/45 (29%) IgM-positive patients who needed dialysis compared to 42/178 (24%) of IgM-negative patients, p= 0.46. The mortality rate was 7/45 (16%) in IgM-positive compared to 52/178 (29%) in IgM-negative patients, p=0.07. Conclusion Patients with positive IgM presented predominantly with jaundice and AKI. There was no statistically significant difference in HIV status and outcomes between the two groups of patients

Realizamos uma investigação epidemiológica em uma zona que fora inundada pela rio Aricanduva e seus afluentes, a leste do município de São Paulo, em 61 coabitantes de casos confirmados laboratorialmente de leptospirose humana ocorridos em 1983, residentes nessa área, com o objetivo de conhecer o nível de infecção por leptospiras nesse grupo de pessoas. Para pesquisa de anticorpos anti-leptospiras realizamos o teste de soroaglutinação microscópica nas 61 amostras de soro colhidas, tendo sido considerado soro reagente aquele que apresentou um título mínimo igual ou superior a 1:100. Para diferenciarmos se a infecção encontrada era recente ou passada, além de outros dados epidemiológicos investigamos a presença de anticorpos da classe IgM nesses soros por meio da prova de hemaglutinação passiva, considerando significante o título igual ou maior que 1:128. Os resultados nos mostraram que 18 pessoas, ou seja 29,6 por cento dos coabitantes eram de prendas domésticas, enquanto que 18,2 por cento eram menores e 6,6 por cento eram aposentados; 6,6 por cento eram operários não qualificados, ficando outras ocupações com 3,3 por cento ou 1,6 por cento . Em relação ao meio ambiente, as unidades residenciais investigadas eram diferentes daquelas descritas na literatura no tocante a casos de leptospirose humana. Estas apresentavam codições de urbanismo, ou seja, eram servidas por transporte coletivo nas proximidades em 95,8 por cento , tinham iluminação pública em 79,2 por cento , apresentavam ruas pavimentadas em 75 por cento , além de serem servidas por rede de esgoto em 70,8 por cento e por rede pública de abastecimento de água em 100. por cento . Quanto ao tipo de construção, 100 por cento era de alvenaria. Em relação a fatores que poderiam favorecer a infecção humana por leptospiras verificamos que quase 90 por cento das unidades residenciais estudadas tinham terrenos baldios a menos de 100 m de distincia, 58,4 por cento apresentavam ratos ou nas próprias dependências ou nas suas proximidades e 79,1 por cento das casas estavam localizadas até 200 m de correntes fluviais. Dos 61 coabitantes estudados, 42 (67,8 por cento ) tiveram um ou mais contato com enchentes, a maioria das quais ocorreram nos meses de janeiro e fevereiro de 1983, época aproximada em que 127 (63,5 por cento ) dos 200 doentes desse ano também o fizeram. Quanto ao nível de infecção, encontramos 6(9,8 por cento ) amostras de soro, reagentes para os sorotipos panama (2), copenhageni (1), javanica (2) e patoc (1). Todos esses dados sugeriram influência do binômio enchente-população murina sobre esse nível de infecção. As 61 amostras de soro examinadas foram negativas para pesquisa de IgM fazendo-nos considerar os soros reagentes como relativos a uma infecção passada, presumivelmente relacionados à época de infecção do caso.
It was investigated actual leptospirosis prevalence, using epidemiological methodology, in a zone that was flood in 1983 by Aricanduva river and their tributaries situated at the east side of São Paulo country. On that time, this zone was affected by human leptospirosis, diagnosticated through laboratory. The population selected for the present survey was a group of 61 human beings who dwelled together with subjects affected by leptospirosis, in order to establish the actual level of infection by leptospira remaining on such a population. In 61 serum samples it was determined the antileptospira anti-body activity following microscopic agglutination test, considering as a reagent serum that having a lower tittle equal or higher than 1:100. In order to differentiate if the infection was either recent or anciently adquired, it was investigated, together with epidemiological data, the presence of antibodies concerning to IgM class using passive hemagglutination test, considering as significant a tittle equalor higher than 1:128. The population distribution according to the occupational activities showed that 29,6 per cent (18subjects) belonged to home task category, 18,2 per cent were children, 6,6 per cent were retired by social security laws, 6,6 per cent non-qualified manual workers. The rest of surveyed population belonged to indetermined or to different labor activities. In relation to living environment, the residential units were different to those previously descrived in cases of human leptospirosis. Houses showed characteristics of an urban environment, having 95,8 per cent a public transport system, 79,2 per cent had public lighting, 75 per cent had streets with pavement, 70,8 per cent showed drainage system and 100 per cent drinking water service. Masonry was detected in 100 per cent of buildings. Those factors which could favor human infection development by leptospira were also studied. It was verified that 90 per cent of residential units showed uncultivated yards in a radio lower to 100 m around the house, 58,4 per cent of cases studied had rats in or near the house and 79,1 per cent of houses were localized near the river (less than 200m). 67,8 per cent (42 subjects) had the chance to contact with flood water once or many times, ocurred most of them, during the months of january or february 1983. At that time, also 127 from 200 patients affected by leptospirosis (63,5 per cent ) had a similar chance of contact with flood water in 1983. It was found that 9,8 per cent (6 cases) of serum samples showed reagents for serovars panama (2), copenhageni (1), javanica (2) and patoc (1). All the data obtained from this research suggest the influence of flood-rat population binomial on the level of infection detected. Looking for IgM, 61 serum samples were found negative, which could be interpreted as the serum reagents were compatible with an past infection, may be related to the time of infection of the cases considered as leptospirosis in 1983.

A serological and questionnaire study on zoonoses was performed among cattle farms in Tanga, Tanzania. The study revealed that leptospirosis and other zoonoses are common in cattle in Tanga. Herd sero-prevalences were 58% for leptospirosis, 12% for brucellosis. 6% for tuberculosis and 12% for toxoplasmosis. Prevalence was higher in traditional herds than in smallholder herds. The zoonoses were not restricted to rural areas, but also occurred in urban and peri-urban areas, where livestock keeping is expanding.

La leptospirose, spirochetose tropicale négligée, est considérée comme la zoonose la plus répandue dans le monde. Selon l’Organisation Mondiale de la Santé, les formes sévères représentent 5 à 15% des infections humaines et le taux de létalité peut varier entre 5% et 30%. En Océanie et particulièrement en Nouvelle-Calédonie et à Futuna, la leptospirose est une préocupation majeure de santé publique: son incidence annuelle moyenne est de 45 pour 100 000 habitants et peut atteindre 150 pour 100 000 habitants pendant les saisons pluvieuses. Malgré les progrès considérables accomplis pour comprendre la physiopathologie de la maladie, plusieurs aspects de la leptospirose encore négligés méritent d’être exploré: les infections symptomatiques pédiatriques, la réaction de Jarisch-Herxheimer (JH) pourtant bien étudiée dans les autres spirochetoses, et les reinfections nécessitant une hospitalisation. Questions posées et objectifs: La pratique clinique suggère que les enfants hospitalisés pour leptosirose sont moins sévèrement atteints que les adultes. Les raisons susceptibles d’expiquer cette différence de présentation sont peu claires. L’obejctif de l’étude 1 était de décrire l’épidemiologie et le profil clinico-biologique des formes pédiatriques de leptospirose nécessitant une hospitalisation en Nouvelle Calédonie et d’identifier des différences en fonction des classes d’âge. La réalité de la réaction de Jarisch-Herxheimer – bien connue dans les autres spirochetoses – reste un sujet controversé dans la leptospirose. Afin d’effectuer une mise au point sur le sujet, une revue systématique de la littérature préalable à été réalisée (Etude 2) avant de préciser la prévalence, la sévérité, et les facteurs de risque des réactions de Jarisch-Herxheimer au cours des épisodes de leptospirose humaine traitée par antibiotiques en Nouvelle Calédonie et à Futuna (Etude 3)
Leptospirosis is an endemo-epidemic zoonotic disease associated with potentially fatal renal, cardiovascular or pulmonary failure. Several aspects of the disease are poorly explored, including infections in children, Jarisch-Herxheimer reactions (JHR) and symptomatic re-infections. The objectives of the studies were the following: to describe disease spectrum and outcome differences in children and adolescents admitted for leptospirosis in a large at-risk population; to quantify frequency of and risk factors for JHR in leptospirosis management; and to assess incidence and characteristics of reinfection by leptospirosis in the Pacific region. Using a retrospective data collection, clinical and laboratory data were obtained on hospitalized confirmed cases in New Caledonia and in Futuna. A case-control study was designed to identify risk factors using a logistic regression model. There are four principal findings from this series of studies with direct implications for clinical practice in those settings. First, leptospirosis in New Caledonia is responsible for a limited number of admissions among children due to milder symptomatic clinical presentation. Second, although generally assumed to be a rare event, the true prevalence of JHR in leptospirosis is unknown in most part of the world. The awareness of this event is probably insufficient considering the significantly high proportion of JHR observed in Futuna. Third, recurrent episodes of symptomatic leptospirosis appear to be non-severe. Finally, specific immunity resulting from a previous episode of leptospirosis with the serovar Copenhageni did not protect against subsequent infection against the same serovar. Future research based those results may provide insights into the still challenging pathogenesis of this complex infectious disease

Para relacionar possíveis variáveis para infecção pelos agentes N. caninum, B. abortus e Leptospira spp em rebanhos bovinos do Estado do Pará utilizando a frequência de anticorpos foram colhidas amostras de sangue de 3466 vacas provenientes de 176 propriedades, nas quais um questionário foi aplicado. A prova de RIFI foi utilizada para pesquisa de anticorpos anti-N.caninum; a prova de triagem do AAT seguida pela SAL e 2-ME como confirmatórias para pesquisa de anticorpos anti-B. abortus; e o método de SAM para pesquisar anticorpos contra Leptospira spp., utilizando uma bateria de 22 antígenos. As análises estatísticas foram realizadas pelas provas do Qui-quadrado (X2) e Mann-Whitney, com intervalo de confiança de 95%. A ocorrência de anticorpos anti-N. caninum, B. abortus e Leptospira spp. em bovinos foi de 14,7%, 3,7% e 65,5% em 87,4%, 41,3% e 98,8% das propriedades analisadas, respectivamente. O sorovar Hardjo foi o mais freqüente, seguido por Wolffi, Grippotyphosa e Hebdomadis, e o mais provável causador da infecção nos animais, seguido de Grippotyphosa, a associação Hardjo+Wolffi e a sorovariedade Wolffi. A presença de abortamentos foi associada à ocorrência de N.caninum (p<0,05), assim como a realização de inseminação artificial e o destino inadequado dos produtos de abortamento foram associados à ocorrência de anticorpos anti-B. abortus e a presença de cães, destino inadequado de vacas que abortaram e a inseminação artificial foram variáveis associadas à ocorrência das sorovariedades Hardjo, Grippotyphosa e Hebdomadis. Demonstrou-se a necessidade de um controle sanitário efetivo para neosporose e leptospirose e de mais estudos para determinar a causa da alta ocorrência do sorovar Grippotyphosa, que pode estar relacionada com a degradação ambiental
Aiming for association of possible infection variables with antibodies frequency of the agents N. caninum, B. abortus and Leptospira spp., 3466 female cattle from 176 herds were examined and a inquiry was applied. IFAT was used for research of antibodies against N. caninum; serum samples were examined for B. abortus antibodies using TAA trial test and SAA plus 2-ME for confirmation; and antibodies against Leptospira spp. were searched using MAT, with a 22 antigens battery. Statistical analysis were performed using Chi-Square (X2) and Mann-Whitney tests, with 95% confidence interval. Occurrence of antibodies against N. caninum, B. abortus and Leptospira spp. in cattle was 14,7%, 3,7% and 65,5% in 87,4%, 41,3% and 98,8% of analysed herds, respectively. Serovar Hardjo was the most frequent, followed by Wolffi, Grippotyphosa and Hebdomadis, and also most probable responsible for infection in animals, followed by Grippotyphosa, Hardjo+Wolffi association and serovar Wolffi. Occurrence of anti-N. caninum antibodies was associated with abortion presence (p<0,05), as artificial insemination and inappropriate destination of abortion products were linked with frequency of antibodies against B. abortus and occurrence of antibodies anti-Hardjo, Grippotyphosa and Hebdomadis was associated with dog presence, inappropriate destination of aborting cows and artificial insemination. It was demonstrated lack of sanitary control for neosporosis and leptospirosis and also necessity for more studies to determine causes for serovar Grippotyphosa high occurrence, condition that may be related with environmental destruction

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-12-10T07:08:27Z No. of bitstreams: 2 Dissertação - Taiã Mairon Peixoto Ribeiro - 2015.pdf: 1116616 bytes, checksum: 188f3991a70516850a90d379351bc899 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-12-10T07:10:56Z (GMT) No. of bitstreams: 2 Dissertação - Taiã Mairon Peixoto Ribeiro - 2015.pdf: 1116616 bytes, checksum: 188f3991a70516850a90d379351bc899 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Made available in DSpace on 2015-12-10T07:10:56Z (GMT). No. of bitstreams: 2 Dissertação - Taiã Mairon Peixoto Ribeiro - 2015.pdf: 1116616 bytes, checksum: 188f3991a70516850a90d379351bc899 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-08-20
Infection with bacteria of the genus Leptospira spp. is the origin of the clinic disease called leptospirosis and has significant impact on equine husbandry and public health. This study aimed to investigate the prevalence of anti-Leptospira spp antibodies. in horses in the municipality of Rorainópolis, State of Roraima, Brazil's Amazon, and identify the predominant serotypes in positive serological reactions, and possible factors associated with the presence of Leptospira spp. A cross-sectional observational study using an epidemiological questionnaire and the collection of 303 samples of equine rural and urban areas that were only entered in the research after reading and signing the informed consent and informed the owner was accomplished. Samples of equine serum used in the research were obtained by puncturing the jugular vein by means of a closed vacuum collection system and sent for analysis by microscopic agglutination test (MAT / MAT) on Leptospirosis Diagnostic Laboratory of the Veterinary School and Animal Science of the Federal University of Goiás. Statistical analyzes were performed using chi-square test that provided evidence of potential factors associated with Leptospira spp. As a result of research, it was observed prevalence of 72.94% of infections in horses, prevalence of 96.43% of foci of infection, and the prevalence of serovars Patoc, Sentot, Icterohaemorrhagiae, Grippotyphosa, Hardjoprajitno and Castellonis in serological reactions positive. Presence of rodents, Veterinary care and Use of animals were found to associads factors for infection by Leptospira spp. Therefore, it was found to endemic infection with Leptospira spp. in the municipality due to the high number of cases and outbreaks, and significant occurrence of positive for the serovars Sentot, Grippotyphosa, Butembo and castellonis indicate the contact and the circulation of these serotypes also in wild animals, and the occurrence of positive for the serovars icterohaemorrhagiae and serovar respectively suggests contact with synanthropic rodents and cattle.
A infecção por bactérias do gênero Leptospira spp. é a origem da enfermidade clínica denominada leptospirose e que possui impacto significativo na pecuária equina e na saúde pública. Este estudo teve como objetivo investigar a prevalência de anticorpos anti-Leptospira spp. em equinos no município de Rorainópolis, Estado de Roraima, Amazônia brasileira, além de identificar os sorovares predominantes nas reações sorológicas positivas, e os possíveis fatores associados à presença da infecção por Leptospira spp. Foi realizado um estudo observacional seccional (transversal) com a utilização de um questionário epidemiológico e a colheita de 303 amostras de equinos da zona rural e urbana que somente foram inseridos na pesquisa após a leitura e assinatura do termo de consentimento livre e esclarecido pelo proprietário. As amostras de soros de equinos utilizados na pesquisa foram obtidas através da punção da veia jugular por meio de sistema fechado de colheita a vácuo e encaminhadas para análise através da soroaglutinação microscópica (SAM/MAT) no Laboratório de Diagnóstico de Leptospirose da Escola de Veterinária e Zootecnia da Universidade Federal de Goiás. As análises estatísticas foram realizadas por meio do teste de chi-quadrado que evidenciassem potenciais fatores associados com a infecção por Leptospira spp. Como resultado da pesquisa, foi constatada prevalência de 72,94% de casos de infecção nos equinos, prevalência de 96,43% de focos de infecção, e a predominância dos sorovares Patoc, Sentot, Icterohaemorrhagiae, Grippotyphosa, Hardjoprajitno e Castellonis nas reações sorológicas positivas. Presença de roedores, Assistência veterinária e o Uso dos animais foram verificados como fatores associados para infecção por Leptospira spp. Portanto, verificou-se a endemicidade da infecção por Leptospira spp. no município devido ao alto número de casos e de focos, e que a ocorrência significativa de positividade para os sorovares Sentot, Grippotyphosa, Butembo e Castellonis indicam o contato e a circulação destes sorovares também em animais silvestres, e a ocorrência de positividade para os sorovares Icterohaemorrhagiae e Hardjo sugere respectivamente o contato com roedores sinantrópicos e bovinos.

Doctor of Philosophy
Department of Diagnostic Medicine/Pathobiology
K.R. Harkin
T.G. Nagaraja
Associations of land cover/land use, socio-economic and housing, and hydrological and soil-hydrological variables were evaluated retrospectively as potential risk factors for canine leptospirosis in Kansas and Nebraska using Geographic Information Systems (GIS). The sample included 94 dogs positive for leptospirosis based on a positive polymerase chain reaction test for leptospires in urine, isolation of leptospires on urine culture, a single reciprocal serum titer of 12,800 or greater, or a four-fold rise in reciprocal serum titers over a 2 to 4 week period; and 185 dogs negative for leptospirosis based on a negative polymerase chain reaction test and reciprocal serum titers less than 400. Publicly available geographic datasets representing land cover/land use, socio-economic and housing characteristics, and hydrologic and soil hydrologic themes were analyzed along with geocoded addresses of case/control locations in GIS. Among different land cover/land use variables evaluated, urban areas (high and medium intensity urban areas and urban areas in general) and evergreen forests and forest/woodlands in general were significant risk factors. Among socio-economic and demographic determinants evaluated, houses lacking complete plumbing facilities, poverty status by age (18-64), and living within 2500 meters of a university/college or parks/forests were significant risk factors. Proximity to water features, hydrologic density and frequently flooded areas were identified as significant risk factors for canine leptospirosis among hydrologic and soil-hydrologic variables. Pet owners whose dogs live in such areas or under these circumstances should consider vaccination to prevent canine leptospirosis.

This chapter consists of short notes, diagrams, and tables to summarize infections caused by spirochaetes. The chapter begins with a classification system to divide these organisms into Treponema, Borrelia, Leptospira, and Brachyspira. Separate sections then follow on the infections of most clinical significance for the tropics and subtropics, including leptospirosis, syphilis, non-venereal treponemes, and relapsing fevers. For ease of reference, each topic is broken down into sections, including classification, epidemiology, microbiology, pathophysiology, clinical syndromes, diagnosis, treatment and prevention.

A wide range of tropical infectious diseases can cause critical illness. Knowledge of the local epidemiology where the disease is acquired is essential. In addition, local resistance patterns of common bacterial pathogens can be very different in tropical countries, so that antibiotic regimens might need adaptation. The ‘surviving sepsis’ guidelines are not always appropriate for the treatment of tropical sepsis. Both diseases require a more restricted fluid management. Leptospirosis is another important tropical disease that can cause sepsis with liver and renal failure or ARDS with pulmonary haemorrhages. Neglected tropical diseases causing neurological syndromes include trypanosomiasis (Sub-Saharan Africa) and rabies. Several viruses in the tropics can cause encephalitis. Recent epidemics of respiratory viruses causing life-threatening pneumonia have had their origins in tropical countries, including severe acute respiratory syndrome, influenza A subtype H5N1 (‘avian influenza’), and recently Middle East respiratory syndrome coronavirus.

The spectrum of acute kidney injury (AKI) encountered in the hospitals of the tropical zone countries is different from that seen in the non-tropical climate countries, most of which are high-income countries. The difference is explained in large part by the influence of environment on the epidemiology of human disease. The key features of geographic regions falling in the tropical zones are climatic, that is, high temperatures and absence of winter frost, and economic, that is, lower levels of income. The causes and presentation of tropical AKI reflect these prevailing cultural, socioeconomic, climatic, and eco-biological characteristics.Peculiarities of tropical climate support the propagation of several infectious organisms that can cause AKI and the disease-transmitting vectors. In contrast to the developed world, where AKI usually develops in already hospitalized patients with multiorgan problems and iatrogenic factors play a major role, tropical AKI is acquired in the community due to issues of public health importance such as safe water, sanitation, infection control, and good obstetric practices. Infections such as malaria, leptospirosis, typhus, HIV, and diarrhoeal diseases; envenomation by animals or insects; ingestion of toxic herbs or chemicals; intravascular haemolysis; poisoning; and obstetric complications form the bulk of AKI in the tropics. Poor access to modern medical facilities and practices such as seeking treatment from traditional faith-healers contribute to poor outcomes.AKI extracts macro- and microeconomic costs from the affected population and reduces productivity. Improvement in the outcomes of tropical AKI requires improvement in basic public health through effective interventions, and accessibility to effective medical care.