Bionomics of Phlebotomine Sandflies at Dhamar City and Neighboring Districts, Yemen.

Background: Phlebotomine sandflies (Diptera: Psychodidae) are small blood-feeding insects of great medical and veterinary significance. Phlebotomine sandflies have long been incriminated as vectors of leishmaniasis in various parts of world. Aim: The main aim of this study was to identify, determine the relative abundance, seasonal distribution and density of phlebotomine sandflies species in Dhamar city and neighboring districts, Dhamar governorate, Yemen. Methods: An entomological study was carried out in Dhamar city and neighboring districts from December 2007 to January 2008. A total of 1007 flies were collected from different parts of the study area. Flies were sampled monthly between December 2007 and January 2008 using sticky traps “Oiled paper” and CDC miniature light traps. Sandflies specimens were identified morphologically using key characters such as pharynx and spermathecae of females and male genitalia. Results: The results of this study revealed that the sticky traps captured 51.4 % of the total sandflies collected, while CDC light captured 48.6%. Out of 1007 specimens examined, 630 (62.6%) and 377(37.4%) were males and females with sex ratio (1.67:1), respectively. Three species of sandflies were identified and all belong to the genus Phlebotomus. The species identified with their relative abundance were P. arabicus (44.1%), P. alexandri (35.2%), and P. sergenti (20.7%). The highest flies abundance was recorded in Utmah district (34.1%), whereas the lowest was in Dhamar city (0.7%) district. Positive correlation was observed between sandfly numbers and rainfall, the sandflies population density was increased with the beginning of the rainy season and reached the peak in July (22.01%) then declined to its lower level in December 0.4%). Conclusion: The present study concludes that phlebotomine sandflies are prevalent in the study areas. Findings of this study are useful for designing control program for combating sandflies and leishmaniasis in Dhamar governorate. [ABSTRACT FROM AUTHOR]