Academic literature on the topic 'Phlebotomus papatasi'

Cutaneous leishmaniasis (CL) is an infectious disease caused by various species ofLeishmaniaand transmitted by several species of sand flies (Diptera: Psychodidae). In order to evaluate the risk of leishmaniasis transmission in Fes-Boulemane, an investigation was carried out in two localities, Aichoun and Bouasseme, during 2011. From January to December, 1120 specimens were collected in Aichoun comprising six species belonging to two genera:Phlebotomus sergenti(76.07%),Phlebotomus longicuspis(9.01%),Phlebotomus perniciosus(8.48%),Phlebotomus papatasi(4.82%),Sergentomyia minuta,andSergentomyia fallax. For Bouasseme, seven species were identified withPhlebotomus sergenti(60.39%) dominating, followed byPhlebotomus perniciosus(20%) andPhlebotomus longicuspis(12.15%). The remaining species,Phlebotomus papatasi,Phlebotomus ariasi,Sergentomyia minuta,andSergentomyia fallax,were less prevalent. The activity of sand flies in both localities is marked by the dominance ofPh. sergentiwith two peaks occurring in June and September. In order to obtain a better understanding of sand fly diversity among their species, results were analyzed by the ecological indices determinant: specific richness, the relative abundance, and Shannon-Weiner index (H′). Further studies of sand fly diversity should employ statistical tests and molecular analyses. This study can be useful in the implementation of appropriate future control measures.

Phlebotomus papatasi, an Old World sand fly species, is primarily responsible for the transmission of leishmaniasis, a highly infectious and potentially lethal disease. International travel, especially military rotations, between domestic locations and P. papatasi-prevalent regions in the Middle East poses an imminent threat to the public health of US citizens. Because of its small size and cryptic morphology, identification of P. papatasi is challenging and labor-intensive. Here, we developed a ribosomal DNA-polymerase chain reaction (PCR)-based diagnostic assay that is capable of detecting P. papatasi genomic DNA from mixed samples containing multiple sand flies native to the Americas. Serial dilution of P. papatasi samples demonstrated that this diagnostic assay could detect one P. papatasi from up to 255 non-target sand flies. Due to its simplicity, sensitivity and specificity, this rapid identification tool is suited for a long-term surveillance program to screen for the presence of P. papatasi in the continental United States and to reveal geographical regions potentially vulnerable to sand fly-borne diseases.

ABSTRACT Leishmania parasites, transmitted by phlebotomine sand flies, are obligate intracellular parasites of macrophages. The sand fly Phlebotomus papatasi is the vector of Leishmania major, a causative agent of cutaneous leishmaniasis in the Old World, and its saliva exacerbates parasite proliferation and lesion growth in experimental cutaneous leishmaniasis. Here we show thatP. papatasi saliva contains a potent inhibitor of protein phosphatase 1 and protein phosphatase 2A of murine macrophages. We further demonstrate that P. papatasi saliva down regulates expression of the inducible nitric oxide synthase gene and reduces nitric oxide production in murine macrophages. Partial biochemical characterization of the protein phosphatase and nitric oxide inhibitor indicated that it is a small, ethanol-soluble molecule resistant to boiling, proteolysis, and DNase and RNase treatments. We suggest that the P. papatasi salivary protein phosphatase inhibitor interferes with the ability of activated macrophages to transmit signals to the nucleus, thereby preventing up regulation of the induced nitric oxide synthase gene and inhibiting the production of nitric oxide. Since nitric oxide is toxic to intracellular parasites, the salivary protein phosphatase inhibitor may be the mechanism by whichP. papatasi saliva exacerbates cutaneous leishmaniasis.

Saliva inoculated by sandfly females during feeding stimulated production of high levels of anti-saliva antibodies. To determine whether 3 species of the genus Phlebotomus have species-specific salivary antigens we performed dot-blots and immunoblots using sera from mice, hamsters and rabbits repeatedly bitten by sandflies. Important differences were found in the antigen components of the salivary gland lysates (SGL) of Phlebotomus papatasi, P. perniciosus and P. halepensis. In total 4–9 species-specific antigens were detected in each species by immunoblotting. Cross-reactivity was not detected between P. papatasi and the other species tested; in the SGL of P. papatasi sera from animals bitten by this species recognized 5–7 major antigens while sera from animals bitten by other species did not react. A weak cross-reaction was observed between P. perniciosus and P. halepensis; in SGL from P. perniciosus, the sera from rabbits and hamsters bitten by this species recognized about 8 intense bands while sera from animals bitten by P. halepensis reacted weakly with up to 4 saliva polypeptides.

Phlebotomine sandflies are vectors of the humans’ and mammals’ parasite Leishmania spp. Although the role of gut microbiome in the biological cycle of insects is acknowledged, we still know little about the factors modulating the composition of the gut microbiota of sandflies. We tested whether host species impose a strong structural effect on the gut microbiota of Phlebotomus spp. Sandflies were collected from the island of Leros, Greece, and classified to P. papatasi, P. neglectus, P. tobbi, and P. similis, all being negative to Leishmania spp. The prokaryotic gut microbiota was determined via 16S rRNA gene amplicon sequencing. Phlebotomus species supported distinct microbial communities (p < 0.001). P. papatasi microbiota was the most distinct over-dominated by three Spiroplasma, Wolbachia and Paenibacillus operational taxonomic units (OTUs), while another Wolbachia OTU prevailed in P. neglectus. Conversely, the microbiota of P. tobbi and P. similis was composed of several less dominant OTUs. Archaea showed low presence with the dominant OTUs belonging to methanogenic Euryarcheota, ammonia-oxidizing Thaumarcheota, and Nanoarchaeota. We provide first insights into the composition of the bacterial and archaeal community of Phlebotomus sandflies and showed that, in the absence of Leishmania, host genotype is the major modulator of Phlebotomus sandfly gut microbiota.

AbstractDDT metabolism in Phlebotomus papatasi (Scopoli) was investigated and compared to that in DDT-resistant and susceptible strains of Culex quinquefasciatus Say and Anopheles gambiae Giles with the objective of establishing baselines for sandfly studies. P. papatasi produced eight metabolites of DDT, with DDE predominating, as in the two mosquito species. Both oxidases and glutathione transferases were found to be involved in DDT metabolism in insecticide-susceptible adults of P. papatasi. The activity level of glutathione transferases and the reduced and oxidized difference spectra of cytochrome P-450 were measured spectrophotometrically. The level of glutathione transferase activity in P. papatasi was lower than that in susceptible C. quinquefasciatus adults when expressed in terms of the activity per milligram of soluble protein but, in contrast, the cytochrome P-450 was slightly higher in both the reduced and oxidized states.

Master of Science
Department of Entomology
Marcelo Ramalho-Ortigao
Sand flies (Diptera:Psychodidae) are vectors of parasites of the genus Leishmania transmitted to suitable vertebrate host during blood feeding. For blood feeding arthropods, including sand flies, blood meal digestion requires the secretion of inhibitory molecules, such as Kazal-type serine proteinase inhibitors that are involved in preventing the blood from coagulating within the mouthparts and the midgut. Previous studies have identified such molecules in mosquitoes, ticks, and triatomine bugs. Following studies of the midgut transcriptome of Phlebotomus papatasi, the principal vector of Leishmania major, two non-classical Kazal-type serine proteinase inhibitors were identified (PpKzl1 and PpKzl2). We are interested in the role of these proteins as inhibitors of coagulation cascades, in addition to their potential effects on blood digestion in P. papatasi. Ppkzl1 is similar to thrombin and trypsin inhibitors in triatomines and mosquitoes and Ppkzl2 is similar to Kazal-type inhibitors in mosquitoes with unknown function. Analyses of expression profiles indicated that although both transcripts are expressed prior to blood feeding in the midgut of P. papatasi they are tightly regulated by the blood meal. Reverse genetics studies using RNAi-targeted knockdown of PpKzl1 and PpKzl2 by dsRNA injection did not result in a detectable effect on mRNA expression levels. Thus, we expressed a recombinant PpKzl2 in a mammalian expression system (CHO-S free style cells) that was applied to in vitro studies to assess activity against various serine proteinases. Recombinant PpKzl2 inhibited chymotrypsin at nanomolar levels and also inhibited thrombin and trypsin at micromolar levels, suggesting that native PpKzl2 is an active serine proteinase inhibitor and may regulate digestive enzymes and thrombin in the midgut. Leishmania development within the sand fly midgut is faced with several barriers that can severely impact the parasites. For transmission to occur, parasites must be able to overcome these barriers including digestive proteinases, escape from the peritrophic matrix, and midgut attachment. Early stages of Leishmania are susceptible to killing by digestive proteinases in the sand fly midgut. Thus, targeting serine proteinase inhibitors may provide a new strategy to prevent transmission of Leishmania.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
As proteínas presentes na saliva dos flebotomíneos possuem uma grande importância na proteção contra parasitas do gênero Leishmania. Uma das proteínas identificadas, denominada de SP15, demonstrou ser responsável pela proteção contra a progressão da doença e aumento do tamanho da lesão em modelos animais. A elaboração de vacinas de múltiplos componentes com proteínas salivares pode ser uma forma viável para o desenvolvimento de vacinas anti-Leishmania. Partindo desta estratégia adotada para elaboração de vacinas, é necessário entender a variabilidade dos genes que codificam proteínas salivares e suas implicações nas respostas imunes dos humanos. Neste trabalho, investigamos a variabilidade genética de SP15 de populações naturais de Phlebotomus papatasi do Oriente Médio. Adicionalmente, associamos a variabilidade genética observada com a predição da estrutura secundária da proteína e possíveis epítopos de ligação a MHC classe II. Os resultados obtidos indicaram um baixo nível de variabilidade genética entre as populações oriundas do Oriente Médio, apesar da ocorrência de um grande número de haplótipos, onde alguns deles são compartilhados entre as populações distintas. Em conjunto, estas observações evidenciam a existência de fluxo gênico ou retenção de polimorfismo ancestral entre as populações e a ausência da seleção purificadora atuando sobre este gene. Para os preditos epítopos de MHC classe II, muitos foram identificados como possuindo sítios de mutação, mas pelo menos três epítopos identificados não apresentaram qualquer tipo de mutação, sugerindo que esta molécula apresenta-se moderadamente conservada e deve induzir respostas imunes uniformes nos humanos

The prevalence of insecticide resistance in vector species around the world is a continuous threat for any success at mitigating the spread of vector-borne diseases. With a limited arsenal of new insecticides, it is crucial for public health programs to understand the geographic range and the genetic mechanisms of resistance to best approach controlling insect vectors. Insecticide resistance is being increasingly observed in phlebotomine sand fly (Diptera: Psychodidae) populations in both the Old World and New World. Sand flies transmit the protozoans that cause leishmaniasis, a disfiguring disease that kills tens of thousands of people each year. The goal of this dissertation was to have both an applied and basic research focus towards understanding resistance in phlebotomines. I began by comparing in vivo and in vitro methods for blood-feeding two species of sand flies, Phlebotomus papatasi and Lutzomyia longipalpis, in the laboratory, both of which are important leishmaniasis vectors. I investigated the susceptibility of both species to ten different insecticides by calculating lethal concentrations that caused varying levels of mortality. Based on these results, I determined diagnostic doses and diagnostic times for both species to the same ten insecticides using an accepted, but novel, assay for sand flies. Finally, I tested for known mechanisms of insecticide resistance in four artificially resistant-selected colonies of sand flies, as well as tested for novel resistance mechanisms. Through applied research, I developed methods for efficient sand fly rearing and for determination of population resistance to insecticides, tools that have worldwide applicability. Through basic research, I determined that laboratory populations of sand flies have sufficient standing genetic variation needed to survive sublethal doses of insecticides; however, I was unable to develop artificially-selected colonies resistant to these insecticides. My research has generated information to provide new insights into the evolution of insecticide resistance in natural sand fly populations. My results support that resistance development may be possible, but evolutionary challenging, an encouraging finding that may be exploited by vector biologists and public health officials to prevent or slow the development of resistance in sand flies to insecticides

Leishmania parasites are the causative agents of a diverse spectrum of infectious diseases termed the leishmaniases. These digenetic parasites exist as intracellular, aflagellate amastigotes in a mammalian host and as extracellular flagellated promastigotes within phlebotomine sand fly vectors of the family Phlebotominae. Within the sand fly vector’s midgut, Leishmania has to undergo a complex differentiation process, termed metacyclogenesis, to transform from non-infective procyclic promastigotes into mammalian-infective metacyclics. Members of our research group have shown previously that parasites deleted for the L. (L.) major cDNA16 locus (a region of chromosome 23 that codes for the stage-regulated HASP and SHERP proteins) do not complete metacyclogenesis in the sand fly midgut, although metacyclic-like stages can be generated in in vitro culture (Sádlová et al. Cell. Micro.2010, 12, 1765-79). To determine the contribution of individual genes in the locus to this phenotype, I have generated a range of 17 mutants in which target HASP and SHERP genes are reintroduced either individually or in combination into their original genomic locations within the L. (L.) major cDNA16 double deletion mutant. All replacement strains have been characterized in vitro with respect to their gene copy number, correct gene integration and stage-regulated protein expression, prior to phenotypic analysis. HASPA1 was not detected in cultured promastigotes, but was expressed in mouse isolated amastigotes. Parasite mutant lines were passaged through susceptible BALB/c mice, during which HASPA2 gene containing mutant lines, in the absence of a HASPA1 gene, were shown not to develop lesions. Mouse-passaged parasites were used to infect the L. (L.) major specific sand fly vectors, Ph. (Ph.) papatasi and Ph. (Ph.) duboscqi. The progress of parasite metacyclogenesis was then monitored over twelve days, by midgut dissection and microscopy. Metacyclogenesis was not fully recovered in any of the replacement mutants tested. Surprisingly, HASPB protein expression could not be detected in the replacement mutants within the sand fly midgut, although HASPB protein was readily detected when the same parasite lines were cultured in vitro. The same was true for SHERP, although in situ expression was recovered in the presence of a HASPB gene, which itself did not expressed detectable HASPB protein levels. These observations suggest a requirement for one or multiple as-yet-unidentified regulatory component(s) for HASPB expression within the sand fly midgut and these are not required in culture. Quantitative PCR data suggested HASPB upregulation to be essential for metacyclogenesis completion, suggesting a sand fly specific function for HASPB.

Doctor of Philosophy
Department of Entomology
Marcelo Ramalho-Ortigao
The emergence and reemergence of vector-borne diseases pose significant threats to humans and other animals worldwide. Although vector control relies mostly on insecticides, the emergence of insecticide resistance urges for the development of new strategies to control the spread of such diseases. For sand fly-transmitted leishmaniasis, Transmission Blocking Vaccines (TBV) may constitute a feasible strategy to impair Leishmania transmission from infected to uninfected vertebrate hosts. Moreover, sand fly saliva-based vaccines represent an alternative or complementary approach as these vaccines protect different mammalian hosts against Leishmania. Based on the potential use of sand fly molecules as vaccines against leishmaniasis, we assessed the potential of Phlebotomus papatasi midgut secreted proteins as TBV candidates and the expression variability of sand fly salivary gland genes. Regarding the TBV approach, we took advantage of the RNA interference (RNAi) technique to evaluate the effects of knocking down P. papatasi midgut-specific genes on Leishmania major development within the sand fly midgut. Whereas peritrophin 1 (PpPer1) knock down led to increased Le. major load by 39%, knocking down chitinase 1 (PpChit1) reduced Le. major load in P. papatasi midguts by 63%. Thus, our data strongly suggest that PpChit1 constitutes a potential target for TBV approaches against Leishmania transmission in endemic areas. Concerning protective vaccines based on salivary gland secreted proteins, we searched for expression polymorphism in selected salivary gland genes in natural and colonized populations of P. papatasi. Significant differences in salivary gland gene expression were not only exhibited in P. papatasi specimens collected in different geographic habitats but also seasonal difference in gene expression was displayed by specimens belonging to the same population. As antigen dose is an important component of immune responses, different doses of salivary protein inoculated into host skin may interfere with vaccine protection. Thus, the efficacy of sand fly saliva-based vaccine upon exposure to different salivary protein doses must be evaluated before deployment in endemic areas. Our data also ruled out some biotic factors as responsible for fine-tuning the expression of such genes. Overall, this dissertation makes significant contribution to the development of sand fly-based vaccines against leishmaniasis.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Flebotomíneos (Diptera: Psychodidae: Phlebotominae) são importantes vetores das leishmanioses, doenças causadas por protozoários do gênero Leishmania, distribuídos em dois grandes gêneros de importância médica: Phlebotomus no Velho Mundo e Lutzomyia no Novo Mundo. Após a ingestão de sangue o bolo alimentar é envolto por uma matriz quitino-proteica, chamada matriz peritrófica (MP). Em uma infecção por Leishmania, o intestino do vetor tem papel crucial, pois, para se estabelecer, o protozoário deve escapar do espaço endoperitrófico e se fixar na parede do intestino para evitar sua eliminação durante a excreção. Nesse sentido, a MP funciona como barreira ao desenvolvimento do parasito, sendo um componente importante na competência vetorial de flebotomíneos. Neste trabalho foi estudado o efeito da alimentação com células sanguíneas reconstituídas com anti-soros específicos para duas proteínas associadas à MP, a quitinase PpChit1 e a peritrofina PpPer2, na morfologia da MP de fêmeas de Phebotomus papatasi. A MP foi avaliada por microscopia de luz (ML) e microscopia eletrônica de transmissão (MET) (24, 42–46, 48 e 72 h após a alimentação), microscopia de força atômica (MFA) (30 h após a alimentação) e microscopia confocal (WGA-FITC) (72 horas após a alimentação). Nesta mesma espécie, também foi estudado a inibição da expressão de PpChit1 pela técnica de RNA de interferência (RNAi) após a injeção de dsPpChit1 (24, 48, 72 e 96 h após a alimentação sanguínea). Adicionalmente, o desenvolvimento pós embrionário do intestino médio foi investigado nas seguintes fases/estágios: larvas de 4o instar com três dias (L4-3) e com cinco dias (L4-5) após a ecdise, pré-pupa, pupa 24 horas e 72 horas após início da metamorfose e adulto recém-emergido, nos flebotomíneos Lutzomyia longipalpis e P. papatasi. Amostras de intestinos médios dissecados de cada fase foram avaliados por microscopias de luz (ML), eletrônica de transmissão (MET) e fluorescência. Verificamos que a alimentação de fêmeas de P. papatasi com antisoros específicos para PpChit1 e PpPer1, levou a um aumento na espessura da MP 72 h após a alimentação, bem como um aumento na amplitude da rugosidade na superfície da MP 30 h após a alimentação. A detecção de quitina com WGA-FITC, identificou que 72 h após a alimentação com anti-PpChit1, o conteúdo de quitina associada a MP no intestino médio do inseto era maior que nos insetos alimentados com soro naïve. A alimentação com antisoros específicos contra as proteínas associadas a MP (PpChit1 e PpPer2) afetam a cinética de maturação e degradação da MP, evidenciando o papel dessas proteínas na estruturação da MP de P. papatasi. A injeção de dsPpChit1 levou a uma reducão nos níveis de transcritos em todos os horários analisados, sendo esses resultados o primeiro passo para contribuir futuramente para o entendimento do papel de PpChit1 na MP P. papatasi. As mudanças morfológicas no intestino médio das duas espécies tiveram início no quarto instar larval, no entanto, em P. papatasi o processo degenerativo das células epiteliais iniciou um pouco antes em L4-3 enquanto que em L. longipalpis em L4-5. Durante a metamorfose, células regerativas foram vistas na base do epitélio, nas duas espécies. Além disso, as marcações positivas para a histona fosforilada H3, em ambas, sugerem que as células regenerativas se dividem durante o processo de remodelamento do intestino médio em flebotomíneos. A histólise do epitélio intestinal larval se dá possivelmente por autofagia, pela presença de numerosos vacúolos autofágicos, bem como por marcações positivas para a proteína LC3, entretanto, a detecção de caspase-3 sugere que a apoptose possa acontecer durante o processo de troca do epitélio larval pelo do adulto. Finalmente, o estudo do remodelamento do intestino médio em P. papatasi e L. longipalpis mostrou de forma inédita que o processo é conservado nas duas espécies, se diferenciando apenas no tempo do início do processo degenerativo entre as duas espécies. Os conhecimentos relacionados as proteínas da MP, bem como ao desenvolvimento pós-embrionário do intestino médio em flebotomíneos, o qual tem papel fundamental na transmissão de Leishmania, são importantes para uma melhor compreensão do inseto vetor.
Sand flies (Diptera: Psychodidae: Phlebotominae) are vectors of Leishmaniasis, a disease caused by parasitic protozoa of the genus Leishmania. They are distributed in two large medical importance genus: Phlebotomus from the Old World, and Lutzomyia from the New World. Leishmania suprapilarian life cycle in the vector midgut begins when insect females intake infected blood with amastigotes forms from the vertebrate host. After the blood meal, the food bolus is surrounded by a chitin-protein layer, called peritrophic matrix (PM). Sand fly midgut plays a crucial role during a Leishmania infection. In order to survive and develop, Leishmania parasites must escape from endoperitrophic space and attach themselves in the intestinal epithelium, preventing excretion with the fecal pellets. The PM can act as a barrier to parasite development, working as a relevant component in the vector competence. This study investigated the effects of reconstituted blood cells feeding with specific antisera targeting two PM associated proteins, chitinase PpChit1 and peritrophin PpPer2 in the PM formation. The PM was studied under light (LM) and transmission electron (TEM) microscopies (24, 42-46 , 48 and 72 h after blood meal), under atomic force microscopy (AFM) (30 h after blood meal) and under confocal microscopy (WGA–FITC) (72 hours after blood meal) in Phlebotomus papatasi. PpChit1 knockdown was performed in P. papatasi by means RNA interference technique (RNAi) after dsPpChit1 injection (24, 48, 72 and 96 h after blood meal). Additionally, the post-embryonic development of the midgut was investigated in the following life-stages: 4th instar larvae three days (L4-3) and five days (L4-5) after molting, pré-pupae, pupae 24 hours and 72 hours, and newly emerged adult in Lutzomyia longipalpis and P. papatasi. Midgut samples from each stage were dissected and assessed by LM, TEM and immunofluorescence. P. papatasi females feeding with anti-PpChit1 and anti-PpPer1 had the PM thickness increased at 72 h after blood meal, as well as a PM roughnes’s amplitude increase at 30 hr after feeding. WGA-FITC staining indicates that PM chitin content on insect midgut was higher in treated individuals than those treated with naïve serum. The feeding of P. papatasi females with red blood cells reconstituted with antisera targeting PM associated proteins (PpChit1 and PpPer2) affected the PM maturation and degradation, indicating the role of these proteins on PM structure. Injection of dsPpChit1 led to significant decrease in corresponding mRNA levels. These results are the first step on contribution to understand PpChit1 role in P. papatasi PM. The midgut metamorphosis in of the two species begins in the 4th instar, however, in P. papatasi, epithelial cells degeneration started shortly, in L4-3, while in L. longipalpis it began in L4-5. Larval gut epithelium degeneration was intensified in pré-pupa in both species by the presence of numerous autophagic vacuoles. During metamorphosis, midgut remodeling occurs by differentiation of stem or regenerative cells to replace larval digestive cells. Regenerative cells were seen at the epithelium basal region in both species. Furthermore, the detection of phosphohistone H3- positive cells suggested that the stem cells can divide during the remodeling process of the midgut. Stem cells in proliferation and differentiation were seen forming the new digestive epithelium in the pupae. Larval midgut replacement possibly occurs by autophagy by the presence of numerous autophagic vacuoles, as well as by the detection of LC3-positive cells. Additionally, cells positive for caspase-3 suggested that the apoptosis may occur during the elimination of larval epithelium. Finally, the study of midgut remodeling in P. papatasi and L. longipalpis was showed for the first time, and this process is conserved in these species, differing only in the time of th beginning of the degenerative processof the midgut epithelium. The study of MP formation as well as the post-embryonic development of the midgut of sandflies represent important steps for a better vector biology understanding.

This chapter presents an analysis of the seasonal activity of the Phlebotomus papatasi (leishmaniasis vector) through a correlation between its monthly activity and the monthly meteorological parameters. Three sites from three leishmaniasis endemic countries were used Morocco, Iran, and Greece. The high density of P. papatasi was observed in May in Greece, in July in Morocco and September in Iran. Before May and after September, an important decrease of P. papatasi activity was observed with a decline of maximum and minimum temperatures and an increase of precipitations. Secondly, strong associations between P. papatasi density and minimum and maximum temperatures were explored, third, no significant association have been detected between P. papatasi abundance and precipitations in the three sites. There is an average correlation between relative humidity and P. papatasi density for Isfahan and Creater Athens. Basically, P. papatasi is sensitive to low temperatures and high relative humidity, which makes these two variables better indicators for the possible emergence of cutaneous leishmaniasis.