Focus Of Cutaneous Leishmaniasis Research Articles

Bionomics of phlebotomine sand flies species (Diptera: Psychodidae) and their natural infection with Leishmania and Crithidia in Fars province, southern Iran.

Phlebotominae sand flies are involved in human diseases, such as leishmaniasis, and cause a considerable number of deaths every year. Besides, some of them have been identified as allergen sources or the potential mechanical vectors related to nosocomial infections. The present study aimed to assess the monthly activity, fauna, and detection of protozoan agents in phlebotomine sand flies using polymerase chain reaction (PCR) in re-emerging zoonotic cutaneous leishmaniasis foci of Shiraz and Kharameh in Fars province, southern Iran during 2016-2017. To determine the monthly activity, sand flies were caught from indoors and outdoors of both studied areas. Afterward, all female phlebotomine sand flies were processed for DNA extraction and PCR assays for Leishmania and Crithidia detections. During the study, 6975 sand flies of 16 species (eight Phlebotomus and eight Sergentomyia species) were caught in both foci. Sand flies' monthly activities started in early April and terminated in late November and October. Additionally, two active peaks of sand flies were observed in both foci; first in June and second in August to September. Phlebotomus papatasi (47.1%) was the most dominant species in out/indoors of both Shiraz (31.1%) and Kharameh (16.0%). It was also the only species which was found infected with Leishmania major, indeed, 2.68% and 2.53% of P. papatasi were infected to L. major in Kharameh and Shiraz, respectively. However, none of the female sand flies was positive for Crithidia spp. Despite various control strategies, especially against Leishmania, considerable cases of leishmaniasis are recorded from Iran every year. Phlebotomine plays the main role in transmission of Leishmania in these foci. Therefore, further studies are needed to determine the role of different phlebotomine species in epidemiological aspects of leishmaniasis.

Clinico-epidemiological features of cutaneous leishmaniasis in Mazandaran Province, northern Iran

IntroductionIran is considered as one of the most important endemic foci of cutaneous leishmaniasis (CL) worldwide. Recently, sporadic cases of CL have been reported in some parts of Mazandaran Province, northern Iran. This study aims to determine the clinical and epidemiological aspects of CL, for the first time, in this area. MethodsAll CL cases registered during 2009–2016 were entered into this descriptive study. Required data was collected from the portal of surveillance system in excel format and entered into SPSS Version 16 software and described as percent frequency, mean, standard deviation, minimum and maximum. The analysis was performed using Chi square and independent T tests. ResultsDuring 2009–2016, 343 subjects were entered into the study. Among investigated patients, 72.6% were male and 87.8% had history of travelling. Mean age of patients was 30.7 years and 21.6% of whom were reported in November while 18.4% were identified in October. The lesions were found in upper limb (39.7%), lower limb (25.7%) and face (6.4%). Of them, 37.3% had one lesion and 22.4% had two lesions. There were no significant difference in the mean age of men and women (p = 0.648) as well as number of lesions in both genders (p = 0.190). ConclusionOur results showed that the most CL cases in the studied area were aged 15–44 most of which had history of recent travelling to endemic areas. According to this study, Mazandaran is not considered as a CL endemic focus and most identified cases were affected following travel to the known endemic Iranian foci of CL.

Leishmania major and Trypanosoma lewisi infection in invasive and native rodents in Senegal.

Bioinvasion is a major public health issue because it can lead to the introduction of pathogens in new areas and favours the emergence of zoonotic diseases. Rodents are prominent invasive species, and act as reservoirs in many zoonotic infectious diseases. The aim of this study was to determine the link between the distribution and spread of two parasite taxa (Leishmania spp. and Trypanosoma lewisi) and the progressive invasion of Senegal by two commensal rodent species (the house mouse Mus musculus domesticus and the black rat Rattus rattus). M. m. domesticus and R. rattus have invaded the northern part and the central/southern part of the country, respectively. Native and invasive rodents were caught in villages and cities along the invasion gradients of both invaders, from coastal localities towards the interior of the land. Molecular diagnosis of the two trypanosomatid infections was performed using spleen specimens. In the north, neither M. m. domesticus nor the native species were carriers of these parasites. Conversely, in the south, 17.5% of R. rattus were infected by L. major and 27.8% by T. lewisi, while very few commensal native rodents were carriers. Prevalence pattern along invasion gradients, together with the knowledge on the geographical distribution of the parasites, suggested that the presence of the two parasites in R. rattus in Senegal is of different origins. Indeed, the invader R. rattus could have been locally infected by the native parasite L. major. Conversely, it could have introduced the exotic parasite T. lewisi in Senegal, the latter appearing to be poorly transmitted to native rodents. Altogether, these data show that R. rattus is a carrier of both parasites and could be responsible for the emergence of new foci of cutaneous leishmaniasis, or for the transmission of atypical human trypanosomiasis in Senegal.

One-year prospective study of pediatric cutaneous leishmaniasis: a neglected tropical disease in sub Himalayan region, India

Background: Satluj Valley of Himachal Pradesh is a newly identified focus of Cutaneous Leishmaniasis (CL) and here disease is still in emerging phase. Although children are most commonly affected victims by CL but till date no such study has been done on childhood CL in this region.Methods: All newly diagnosed cases of CL were registered and detailed clinico-epidemiological parameters of children between 0-18 years were recorded. Imprint smears for LD bodies and biopsies for histopathology were done in atypical cases to confirm clinical diagnosis.Results: Over a period of one year 337 cases of CL were registered, out of them 115 children (0-18 years) were enrolled for this study. School going (6-18 years) population was predominantly affected age group. Males outnumbered the females with a ratio of 1.88. Face was most commonly affected site and most (65.21%) cases presented with single lesion. Nodules (40.87%), plaques (24.35%) and papules (7.39%) were commonly observed morphologies although mixed patterns and atypical forms were also found. Most (62.60%) cases presented within 1-3 months of lesion onset. All cases responded well to treatment with antimonials. Lesional pain, swelling, bleeding, pigmentation and scarring were minor post treatment side effects.Conclusions: Pediatric CL is an emerging infection along the Satluj valley of Himachal Pradesh (HP). Although clinical diagnosis is simple, and all cases respond well to antimonials. But, availability of diagnostic tests is essential to diagnose atypical cases. Further annual record keeping, and reporting is recommended to know the exact disease burden so as to promote the effective treatment and preventive measures.

A newly emerged focus of zoonotic cutaneous leishmaniasis in South-western Iran

Leishmaniasis is rising in many countries, including Iran, due to climate change, refugee crises, urbanization and etc. The aim of this study was to explore the epidemiology, extent and identity of Leishmania species in a newly emerged focus in Abdanan County, Ilam Province, South-western Iran. This study was performed as a descriptive cross-sectional study by a systematic house-to-house approach. The Leishmania species was identified by RFLP-PCR and sequencing. Altogether, 46799 individuals consisting of 22907 (48.9) female and 23892 (51.1%) male were interviewed and physically examined for the presence of skin lesions. Overall, the incidence rate was 0.34% (n = 160). All age groups were affected and the incidence rate was the highest in <10 years of age group (0.49%) and the lowest in >50 years old individuals (0.15%), although there was no significant difference regarding the sex and age. The majority of patients had one lesion (47.5%) on hands (56%) and most of the cases occurred in Abdanan city (%54) in summer. Based on the RFLP-PCR analysis, all the Leishmania isolates were L. major of single genotype. A newly emerged focus of zoonotic CL caused by L. major occurred in South-western of Iran. Multiple risk factors created this epidemic area. Further studies on the vector and reservoir are crucial needed to provide evidences to select the prophylactic and therapeutic measures for future control strategies.

Molecular identification of Leishmania infection in the most relevant sand fly species and in patient skin samples from a cutaneous leishmaniasis focus, in Morocco.

BackgroundCutaneous leishmaniasis (CL) is an infectious disease caused by various species of Leishmania and transmitted by several species of sand flies. CL is among the most neglected tropical diseases, and it has represented a major health threat over the past 20 years in Morocco. The main objectives of this study were to identify relevant sand fly species and detect Leishmania infection in the most prevalent species and patient skin samples in Taza, a focus of CL in North-eastern Morocco.Methodology and findingA total of 3672 sand flies were collected by CDC miniature light traps. Morphological identification permitted the identification of 13 species, namely 10 Phlebotomus species and 3 Sergentomyia species. P. longicuspis was the most abundant species, comprising 64.08% of the total collected sand flies, followed by P. sergenti (20.1%) and P. perniciosus (8.45%). Using nested-kDNA PCR, seven pools of P. sergenti were positive to Leishmania tropica DNA, whereas 23 pools of P. longicuspis and 4 pools of P. perniciosus tested positive for Leishmania infantum DNA. The rates of P. longicuspis and P. perniciosus Leishmania infection were 2.51% (23/915) and 7.27% (4/55), respectively, whereas the infection prevalence of P. sergenti was 3.24%. We also extracted DNA from lesion smears of 12 patients suspected of CL, among them nine patients were positive with enzymatic digestion of ITS1 by HaeIII revealing two profiles. The most abundant profile, present in eight patients, was identical to L. infantum, whereas L. tropica was found in one patient. The results of RFLP were confirmed by sequencing of the ITS1 DNA region.ConclusionThis is the first molecular detection of L. tropica and L. infantum in P. sergenti and P. longicuspis, respectively, in this CL focus. Infection of P. perniciosus by L. infantum was identified for the first time in Morocco. This study also underlined the predominance of L. infantum and its vector in this region, in which L. tropica has been considered the causative agent of CL for more than 20 years.

Faune phlébotomienne du foyer leishmanien de Keur Moussa : données actuelles sur la diversité et variations saisonnières (Thiès, Sénégal)

An inter-epidemic oversight was conducted in the cutaneous leishmaniasis focus of Keur Moussa (Thies region) between June 2015 and October 2016, more than 20 years after the last epidemic. The three sampling methods (adhesive traps, CDC light traps, and indoor pyrethroids sprays) allowed the capture of 1,746 sand flies belonging to 2 genera and 24 species, those involved in the transmission of leishmaniasis in Senegal, as well as 11 new species for the focus. The vector of human cutaneous leishmaniasis in Senegal, Phlebotomus duboscqi Neveu-Lemaire, 1906, represents 10.9% of this fauna. Sergentomyia schwetzi, one of the species involved, with Sergentomyia dubia and Sergentomyia magna, in the transmission of canine leishmaniasis in Senegal, is the most abundant species with 38.1% of the samples. The other two species have individually smaller percentages. Seasonal variations of the abundance show an intense activity of sandflies at the end of the dry season under the influence of high average temperatures and a humidity exceeding 50%. Rains are a limiting factor. According to the enrichment of the fauna and the high density of the different vectors of leishmaniasis in this focus, particularly P. duboscqi, a specific importance should be given for this focus in order to prevent occurrence of epidemics.

Distribution and ecological aspects of sand flies (Diptera: Psychodidae) species in Northeastern Iran

Objective: To determine both the distribution and the ecological characteristics of sand flies in Golestan Province, northeast of Iran in 2016. Methods: In this study, 34 villages were selected based on their geographical conditions. Sticky paper traps were used for collecting the sand flies. Sampling was carried out in each of villages from May to November. In each village, 60 traps for indoors and 60 for outdoors were monthly installed. The species of all collected sand flies were determined using approved morphological keys. Pearson coefficient correlation was used to find the relationship between the number of collected Phlebotomus papatasi from different villages and incidence rate of zoonotic cutaneous leishmaniasis as well as the number of positive cases of the disease. The altitude of the studied villages was extracted from digital elevation model of the area using GIS and vegetation cover density index of the province was extracted from Modis satellite imagery and distribution map of sand flies drown up. Results: Overall, 5 428 sand flies were collected and identified, belonging to 18 species. Phlebotomus wenyoni was reported for the first time from the area in this study. The frequency of sand flies in the villages located in northeast of the Golestan province (the plateau area, lower altitude, arid and semi-arid climates, and lower vegetation cover density), were more than other villages in this province. There was a significant correlation between the number of collected Phlebotomus papatasi and incidence rate of the zoonotic cutaneous leishmaniasis cases in different villages (r=0.837, P=0.019) as well as the number of positive cases of the disease (r=0.688, P<0.001). Conclusions: In the northeaster areas of Golestan Province which is known as the endemic foci of zoonotic cutaneous leishmaniasis, the abundance of sand flies were more and the conditions for their growth and development were more appropriate.

Co-detection and isolation of Leishmania and Crithidia among naturally infected Tatera indica (Rodentia: Muridae) in Fars province, southern Iran

Objective: To explore the co-detection of natural infection of Trypanosomatidae parasites such as Leishmania and Crithidia in reservoir hosts of leishmaniasis. Methods: Rodent populations were monitored in two endemic foci of cutaneous leishmaniasis of Fars province, southern Iran from March to October 2016. Rodents were trapped alive in several parts of Shiraz and Kharameh cities. Afterwards, their organs were prepared for detection of Leishmania and Crithidia species by molecular, microscopic, and culture methods. Results: Totally, 115 rodents of five species; Tatera indica (T. indica) (85), Rattus rattus (12), Meriones libycus (9), Mus musculus (7), and Rattus norvegicus (2), were trapped alive and their tissue samples were examined using microscopic, cultivation, and molecular assays. Overall, 59 (51.3%) rodents were positive for Leishmania or Crithidia parasites. The highest rate (61.2%; 52/85) of Leishmania infection was related to the T. indica population. The cultivation, and molecular observations showed that two (2.4%; 2/85) of T. indica (foot-pad, and spleen samples) were positive to Crithidia. Conclusions: This is the first report of Crithidia infection in T. indica in Iran. Consequently, more epidemiological and ecological studies are needed to understand the role of Crithidia and Leishmania in T. indica.

Identification of Leishmania species using N-acetylglucosamine-1-phosphate transferase gene in a zoonotic cutaneous leishmaniasis focus of Iran.

Ilam province is one of the oldest known endemic foci of zoonotic cutaneous leishmani- asis (CL) in Iran; and the recent studies have shown an increasing trend in the number of cases from the region. This study was aimed to investigate the parasite species and genetic diversity of isolates obtained from CL patients based on the N-acetylglucosamine-1-phosphate transferase (nagt) gene. Exudate materials were collected from the swollen margin of the skin lesions of the patients suspected with CL who were referred to health centers laboratory of Mehran, Dehloran, Ilam and Malekshahi cities in the Ilam province. Demographic data were collected through a questionnaire. Smears were stained and examined microscopically. In total, 62 parasitologically positive samples were subjected to PCR-RFLP of nagt gene for identification of Leishmania species, in addition to genetic diversity investigation. Nearly, half of the positive cases were referred from Mehran followed by Dehloran City (40.4%). These included people from different age groups (1 to 73 yr), with majority being male (66.1%). The common site of lesions was hand (48.4%). Half of the patients had multiple lesions; most of them were wet ulcerative type. A 1450-60 bp band of the nagt gene was amplified from all the samples. Digestion patterns of acetyl-coenzyme A carboxylase 1 (ACC1) enzyme were similar to what expected for Leishmania major. No difference was observed at the nucleotide acid level or resulting amino acid in nine sequenced samples on the basis of phylogenetic analyses. However, intra- species differences (0.0015) were observed amongst the L. major isolates of present study and the other parts of Iran. The findings of this study demonstrated that the main causative agent of CL in Ilam Province is L. major, and there is no considerable heterogeneity among the L. major isolates. Moreover, nagt gene proved to be an efficient marker for differentiating Leishmania species. Further studies with more samples need to be carried out to achieve a more comprehensive result on the genetic variation of L. major isolates.

Role of environmental, climatic risk factors and livestock animals on the occurrence of cutaneous leishmaniasis in newly emerging focus in Iran.

Occurrence of leishmaniasis is affected by various biological and environmental factors. Kohgiluye and Boyerahmad (K-B) province is an emerging focus of cutaneous leishmaniasis (CL) in Southwest Iran. To elucidate some angles of occurrence of CL in this province, climatic and environmental factors and close proximity to livestock were studied by univariate and two multivariate logistic regression models. The dwelling addresses of 275 CL patients were obtained from Health Centers records for a 5 years period. The effect of mean annual temperature, minimum mean annual temperature, maximum mean annual temperature, mean annual rainfall, slope, elevation, land covers and close proximity to cattle and sheep/goat sheds on the occurrence of CL were analysed using geographical information systems (GIS) approach. CL occurred in all counties with the most cases in Northwest, West and South semi-arid and warm regions. Land cover, slope, elevation and close proximity to cattle sheds, were the most effective factors. Urban, dry farm and thin rangeland were found as the most important land covers. Slope and elevation decreased the probability of disease. Close proximity to cattle sheds notably increased the chance of CL. The importance of other factors such as rainfall, temperature and close proximity to sheep/goat sheds only were shown when their effects were evaluated independently from other factors. So regions with urban, dry farm and thin rangeland covers with lower slope and altitude where in close proximity of cattle sheds seems to be potentially most high risk areas. Distribution of CL cases is influenced by combination of environmental, ecological factors and close proximity to livestock sheds but control programs should be focused on cities and villages in the above-mentioned most high risk regions.

Phlebotomus halepensis (Diptera: Psychodidae) Vectorial Capacity in Afyon and Nigde Province, Turkey.

Leishmaniasis is a one of the vector-borne diseases and has two clinical forms in Turkey: cutaneous and visceral. The aim of this study was to determine the sand fly fauna in Afyon and Nigde provinces where endemic foci of cutaneous leishmaniasis (CL) in Turkey. In Afyon, 2,259 sand flies were collected in 73 locations in August 2009 and August 2010, using CDC light traps. In total, eight Phlebotomus species were identified; Phlebotomus halepensis (47.41%), Phlebotomus papatasi (31.42%), Phlebotomus neglectus/syriacus (9.38%), Phlebotomus balcanicus (7.48%), Phlebotomus simici (2.12%), Phlebotomus perfiliewi (1.90%), Phlebotomus sergenti (0.08%), Phlebotomus similis (0.13%), and Sergentomyia dentata (0.04%). A total of 418 sand fly specimens were caught by CDC light traps in 40 stations in Nigde in September 2009 and September 2010. In total, seven Phlebotomus species were identified; P. halepensis (74.16%), P. simici (13.87%), P. papatasi (3.82%), P. neglectus/syriacus (2.87%), P. balcanicus (2.63%), P. sergenti (2.39%), and Phlebotomus tobbi (0.23%). Collected sand flies were examined by microscope, and no promastigotes were found in their midguts. We categorized and pooled female specimens (1,031 females, 73 pools of 2-33 individuals). Leishmania species-specific ITS1 real-time PCR assay was performed for detection and identification of parasites. We detected 6 of the 73 pools with Leishmania tropica (Ross, 1903), (Trypanosomatidae). In conclusion, P. halepensis was found to be dominant species in both areas. We are in opinion that our findings support P. halepensis vectorial role for L. tropica in nature and it could be responsible for the transmission of L. tropica in these endemic areas.

Emergence of visceral leishmaniasis in Sri Lanka: a newly established health threat

Background: Sri Lanka is a new focus of human cutaneous leishmaniasis caused by a genetic variant of usually visceralizing parasite Leishmania donovani. Over 3000 cases have been reported to our institution alone, during the past two decades. Recent emergence of visceral leishmaniasis is of concern.Methods: Patients suspected of having visceral leishmaniasis (n = 120) fulfilling at least two of six criteria (fever > 2 weeks, weight loss, tiredness affecting daily functions, splenomegaly, hepatomegaly and anemia) were studied using clinic-epidemiological, immunological and haematological parameters. Seven cases (four progressive, treated (group A) and 3 non- progressive, potentially asymptomatic and observed (group B) were identified. Clinical cases were treated with systemic sodium stibogluconate or amphotericin B and all were followed up at the leishmaniasis clinic of University of Colombo for 3 years with one case followed up for 9 years.Results: All treated cases responded well to anti leishmanial treatment. Relapses were not noticed. Clinical features subsided in all non-progressive cases and did not develop suggestive clinical features or change of laboratory parameters. Visceral leishmaniasis cases have been originated from different districts within the country. Majority had a travel history to identified local foci of cutaneous leishmaniasis.Conclusion: Visceral leishmaniasis is recognized as an emerging health threat in Sri Lanka. At least a proportion of locally identified strains of L. donovani possess the ability to visceralize. Apparent anti leishmanial sensitivity is encouraging. Timely efforts in disease containment will be important in which accurate understanding of transmission characteristics, increased professional and community awareness, improved diagnostics and availability of appropriate treatment regimens.

Geographical Information Systems in Determination of Cutaneous Leishmaniasis Spatial Risk Level Based on Distribution of Vector Species in Imamoglu Province, Adana.

The Imamoglu district located in the southeast of Adana province in Turkey is an endemic focus of cutaneous leishmaniasis (CL) owing to dominancy of Phlebotomus tobbi, which is a probable vector of Leishmania infantum. About 11.26% of CL cases reported each year are from Imamoglu, Adana, and between 2008 and 2015, 223 cases of CL were reported. Leishmania infantum, which may be transmitted by P. tobbi, Phlebotomus neglectus/syriacus, and Phlebotomus perfiliewi, is referred as leishmaniasis factor in Adana. Thus, the aim of this study was to map the risk areas for each sand fly species using remote sensing images based on environmental factors and geographical characteristics. Two field works in two consecutive years (2013 and 2014) were conducted and six sand fly species were caught, four of which were identified as probable vector species. Field work results were compared with environmental data obtained from satellite images by univariate and binary logistic regression in PASW. ARCMAP 10.2 software was used for geographical adjustments, creating a database and estimating a risk model by using previous risk value formulas. The results showed that the distribution of three probable leishmaniasis vectors (P. tobbi, P. neglectus/syriacus, and P. perfiliewi) was associated with normalized difference vegetation index (NDVI), digital elevation model (DEM), night-time land surface temperature (LSTNIGHT), and emissivity (EMIS31) values, which were related to the local authorities, who take these findings into account when deciding on high risk areas for CL.

Identification of Leishmania Species for Cutaneous leishmaniasis in Gonabad, Bardaskan and Kashmar, Central Khorasan, 2015

Background: About 90% of cutaneous leishmaniasis (CL) cases are reported from 7 countries including Iran. In this study, the cutaneous leishmaniasis species causing CL in Gonabad, Bardaskan, Kashmar cities in central Khorasan (Iran) were identified by kDNA-PCR. Methods: During the study, 93 suspected patients with CL, who were referred to the dermatology research center in these cities, were evaluated based on age, clinical forms, and place of residence. Direct microscopy was employed for parasitological diagnosis and PCR from skin ulcers performed using specific kDNA primers. Data were analyzed using the SPSS software. Results: Among 93 individuals with skin ulcers suspected to CL, the results of 81 direct smears were positive. PCR bands were observed in 84 examined samples, of which 68 (81%) samples were identified for Leishmania tropica and 16 (19%) samples for L. major. 12 patients were from Bardaskan with 10 cases of L. tropica, 23 patients from Gonabad with 20 cases of L. tropica, and 49 patients from Kashmar with 38 cases of L. tropica. Most of the lesions were located on hands (37%), the most clinical feature was papule (75%), and most of patients were 21 - 30 years old. Conclusions: Previous epidemiologic studies have indicated that anthroponotic cutaneous leishmaniasis is the only dominant CL in the center and south of Khorasan. However, this study introduced new foci of zoonotic cutaneous leishmaniasis in these areas. Kashmar city was introduced as a new focus of zoonotic cutaneous leishmaniasis.

No Evidence of Interspecific Genetic Exchange by Multi-Locus Microsatellite Typing Between Leishmania Killicki and Leishmania Major in a Mixed Focus of Cutaneous Leishmaniasis in Southeast Tunisia

Sixty-four Leishmania samples were isolated from patients in several villages in the Tataouine governorate, southeast Tunisia. This region is known to be a mixed focus of human cutaneous Leishmaniasis caused by Leishmania (L.) killicki (synonymous L. tropica) and L. major. To identify the Leishmania species in this governorate, a nested polymerase chain reaction based on the variable region of the kinetoplast minicircle was performed on each isolate. Multi-locus microsatellite typing using markers selected for their ability to amplify the two species was used to explore patterns of interspecific genetic exchange. Thirteen L. major and 51 L. killicki isolates were identified. The analysis of microsatellite data showed very low genetic diversity in each species with this set of microsatellites but a high differentiation between the two species. Nine L. major and five L. killicki strains revealed heterozygous genotypes with no shared allele between the two species. These heterozygotes probably resulted from genetic mutation events and not from interspecific genetic exchange. Specific and different epidemiological cycles at the sympatric level might explain the absence of genetic exchange between the two Leishmania species in the Tataouine governorate.

Some ecological aspects of Phlebotomine sand flies (Diptera: Psychodidae) in an endemic area of leishmaniasis in Darab district, Fars province, southern Iran

Background: Phlebotomus species are solely responsible for transmitting leishmaniasis in the old world. The disease is endemic in several parts of Iran. Darab district located in Fars province of southern Iran is one of the most important endemic foci of cutaneous leishmaniasis. Sand flies and Methods: To identify the distribution of sand flies, a total of 5019 sand flies were collected in Darab district from May to September 2012. To determine the monthly activity, 2039 sand flies were biweekly collected from indoors and outdoors of two villages at lowland and highland regions. The relationship between the frequency of sand flies and wind speed (greater than 3 m/s as the influential factor) was studied. To determine the number of sand flies' bites per night, a native volunteer exposed his body every 1 h from sunset to sunrise. Results: In total, 13 species of Phlebotomine (five Phlebotomus spp. and eight Sergentomyia spp.) were identified. Besides, a relatively significant relationship was found between the frequency of sand flies and wind speed more than 3 m/s, especially in June and July 2012. Moreover, evaluation of the night blood-feeding peak during 8:00 P.M.–6:00 A.M. indicated that most bites occurred at 11:00-12:00 P.M. and 9:00-10:00 P.M. with 125 and 110 bites, respectively. Conclusion: Phlebotomus papatasi was the dominant species (49.2%). Additionally, wind speed more than 3 m/s showed a preventive effect on sand flies' activity. Thus, insecticide-treated nets are recommended to be used for all inhabitants, especially children and pregnant women, to prevent sand flies' bites through the night.

Susceptibility status of wild population of Phlebotomus sergenti (Diptera: Psychodidae) to different imagicides in a endemic focus of cutaneous leishmaniasis in northeast of Iran.

Phlebotomine sandflies (Diptera: Psychodidae) transmit several important zoonotic diseases to humans and leishmaniasis is one of them. Two types of leishmaniasis, viz. visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are endemic in Iran. The main vector of anthroponotic cutaneous leishmaniasis (ACL) is Phlebotomus sergenti. The aim of the present study was to determine the susceptibility status of wild strain of P. sergenti to different imagicides of DDT, bendiocarb and permethrin at the median lethal time, LT50 level. Sandflies were collected from selected village in North Khorasan Province, northeast of Iran from indoors using CDC light-traps. Susceptibility test was carried out against DDT (4%), bendiocarb (0.1%) and permethrin (0.75%) for all the females according to WHO method, and mortality was calculated. Species identification was carried out using the morphological keys. Data were analysed using probit regression analysis to determine the LT50 and LT90 values. In total, 851 female P. sergenti sandflies were tested. LT50 values to DDT (4%), Bendiocarb (0.1%) and permethrin (0.75%) were 15.4, 19.2 and 6.3 min respectively. The values for LT90 were 51.1, 47.4 and 18.6 min respectively. The mortality rates for 1 h exposure time to DDT, bendiocarb and permethrin were 89.8 ± 1.4; 93.6 ± 1.4; and 95.6 ± 1.7%, respectively. The suscesptibility studies revealed development of resistance against DDT (4%) in the wild strain of P. sergenti population. Monitoring and mapping of insecticide resistance in the region is recommended for vector control.

Diversity and ecology of sand flies (Psychodidae: Phlebotominae): foci of cutaneous leishmaniasis in Amazon Region, Brazil

Diversity and ecology of sand flies (Psychodidae: Phlebotominae): foci of cutaneous leishmaniasis in Amazon Region, Brazil

Current knowledge of sand fly fauna (Diptera: Psychodidae) of northwestern Yemen and how it relates to leishmaniasis transmission

This report presents the results of the first entomological survey of the sand fly fauna in northwestern Yemen. Sand flies were collected using sticky paper traps and CDC light traps from Hajjah governorate, a cutaneous leishmaniasis focus due to Leishmania tropica. Six Phlebotomus species: P. alexandri, P. arabicus. P. bergeroti, P. orientalis, P. papatasi, P. sergenti and ten Sergentomyia species: S. africana, S. antennata, S. christophersi, S. dolichopa, S. dreyfussi, S. fallax, S. multidens, S. taizi, S. tiberiadis, S. yusafi were identified. P. alexandri was the most predominant Phlebotomus species and P. papatasi was a scarce species. S. fallax was the principal Sergentomyia species and S. dolichopa was the least species encountered. The diversity of the sand fly fauna within and among three altitudinal ranges using Simpson index and Jaccard's diversity coefficient respectively were measured. High species diversity was found in all altitude ranges. There seemed to be more association between sand fly fauna in higher altitudes with fauna from moderate altitudes. Sand fly seasonal activity showed a mono-modal trend in the lowland and a confluent bimodal trend in the highlands. Leishmania DNA could not be detected from 150 Phlebotomus females using PCR-RFLP. A possible zoonotic cutaneous transmission cycle due to Leishmania tropica in northwestern Yemen would involve P. arabicus as the sand fly vector and the rock hyrax as the reservoir host. The vector competence for P. alexandri as a vector of visceral leishmaniasis in Hajjah governorate is discussed.