Spatial distribution and infection rate of leishmaniasis vectors (Diptera: Psychodidae) in Ardabil Province, Northwest of Iran

Objective: To determine the spatial distribution and infection rate of sand flies as vectors of Leishmania parasite in Ardabil province, northwest of Iran. Methods: This was a descriptive cross-sectional study. The sand flies were collected from 30 areas in all 10 districts of Ardabil province during 2017. The specimens were caught using the sticky traps. The head and genitalia of sand flies were separated and mounted in Berlese solution for microscopic identification. The Geographical Information System ArcMap10.4.1 software was used to provide the spatial maps. Results: A total of 2794 sand flies specimens were collected and 22 species of sand flies were identified from the two genera: Phlebotomus and Sergentomyia from Ardabil province. The highest frequency was found in Phlebotomus papatasi (23.7％) followed by Phlebotomus kandelakii (13.0％). The promastigote form of Leishmania infantum parasite has been reported from the three main vectors of visceral leishmaniasis (Phlebotomus kandelakii, Phlebotomus perfiliewi and Phlebotomus tobbi) from Ardabil province, where the spatial distribution map of these visceral leishmaniasis vectors was prepared. Some important species of sand flies such as Phlebotomus kandelakii, Phlebotomus perfiliewi and Phlebotomus tobbi were reported and identified as main and probable vectors of visceral leishmaniasis in Ardabil. Conclusions: According to the Geographic Information System based maps, the frequency of the sand flies as leishmaniasis vectors, the leishmania parasite infection rate and the prevalence of the disease in the central areas of Ardabil province are higher than in other areas in Ardabil province.

Spatial distribution of sand flies (Diptera: Psychodidae; Larroussius group), the vectors of visceral leishmaniasis in Northwest of Iran

Objective: To determine spatial distribution of sand flies (Diptera: Psychodidae; Larroussius group), the vectors of visceral leishmaniasis in Ardabil province, Northwest of Iran. Methods:Sand flies were collected using sticky traps from the 30 selected points in Ardabil province, during May-November 2017. The MaxEnt model in GIS software was used for modeling. Results: A total of 2794 specimens of sand flies were collected, of which 33％ were Larroussius subgenus sand flies. Phlebotomus kandelakii and Phlebotomus wenyoni were the highest and lowest collected species respectively. Based on the modeling, four areas in the province were identified with more than 70％ probability of the presence of Larroussius group vectors which were at risk of visceral leishmaniasis disease transmission. Conclusions: The distribution of Larroussius subgenus sand flies was observed in all parts of Ardabil. But the northern parts of the province (Germi and Bilesavar counties) as well as central part (Ardabil and Meshkinshahr counties) were of great importance in terms of the presence of Larroussius subgenus sand flies and the possibility of transmission of the visceral leishmaniasis.

Molecular characterization, biological forms and sporozoite rate of Anopheles stephensi in southern Iran

Objective: To identify the biological forms, sporozoite rate and molecular characterization of the Anopheles stephensi (An. stephensi) in Hormozgan and Sistan-Baluchistan provinces, the most important malarious areas in Iran. Methods: Wild live An. stephensi samples were collected from different malarious areas in southern Iran. The biological forms were identified based on number of egg-ridges. Molecular characterization of biological forms was verified by analysis of the mitochondrial cytochrome oxidase subunit I and II (mtDNA-COI/COII). The Plasmodium infection was examined in the wild female specimens by species-specific nested–PCR method. Results: Results showed that all three biological forms including mysorensis, intermediate and type are present in the study areas. Molecular investigations revealed no genetic variation between mtDNA COI/COII sequences of the biological forms and no Plasmodium parasites was detected in the collected mosquito samples. Conclusions:Presence of three biological forms with identical sequences showed that the known biological forms belong to a single taxon and the various vectorial capacities reported for these forms are more likely corresponded to other epidemiological factors than to the morphotype of the populations. Lack of malaria parasite infection in An. stephensi, the most important vector of malaria, may be partly due to the success and achievement of ongoing active malaria control program in the region.