Topographical distribution of anopheline mosquitoes in an area under elimination programme in the south of Iran

Background: Malaria is a major vector-borne disease in tropical and sub-tropical countries caused by Plasmodium infection. It is one the most important health problem in south and southeast of Iran. Since Iran has recently launched to the elimination phase of malaria and vector control is one of the main strategies for elimination, this study was conducted to determine the topographical distribution of malaria vectors in Minab County, one of the important malaria endemic areas in south of Iran. Methods: In this cross-sectional study, six villages in three topographically different sites namely coastal plain, foothill and mountainous areas were selected by simple random sampling. The anopheline larvae were collected using the standard dipping method. The specimens were identified using a morphology based-key. Statistical analyses were performed using SPSS ver.16 software. Results: In total, 3,841 anopheles larvae were collected from 24 larval habitats. They consisted of ten species: Anopheles moghulensis (25.23%), Anopheles stephensi (24.47%), Anopheles dthali (19.14%), Anopheles culicifacies (9.63%), Anopheles fluviatilis (7.52%), Anopheles superpictus (5.62%), Anopheles turkhudi (5.55%), Anopheles pulcherrimus (1.93%), Anopheles multicolor (0.47%), and Anopheles apoci (0.44%). Most species were distributed in different topographies and only An. Stephensi and An. culicifacies, the main malaria vectors in Iran, were significantly associated with the altitude of studied areas. An. moghulensis, An. stephensi and An. dthali were the most widespread species and were, respectively predominant in Coastal plain, foothill and mountainous areas. Conclusion: Results of this study have revealed that there are many malaria vectors that are distributed in Minab County and some of them are expected to be predominant in areas with special topographic characteristics. This finding can provide a basis for effective planning and implementation of evidence-based malaria vector intervention strategies towards vector control, which may help in malaria elimination in the study area.