Comparison of the Life Cycle and the Survival Strategies of two Sand Fly Vectors of Leishmanaisis

Phlebotomine sand flies are hematophagus insects responsible for transmission of Leishmania parasites, the causative agents of the group of diseases known as leishmaniasis. These diseases cause a number of manifestations in humans, ranging from self healing lesions (cutaneous leishmaniasis) to the fatal disease syndrome known as visceral leishmaniasis (kala azar, VL). Understanding the life cycle strategies of sand flies is a key to understanding the epidemiology of leishmaniasis. The aim of this study was to compare the life cycle of two sand fly species; Lutzomyia longipalpis , the vector of the parasite causing visceral leishmaniasis in Latin America and Phlebotmus duboscqi , the vector of the parasite causing cutaneous leishmaniasis in West Africa. Females from the two species were offered blood meals on mice and allowed to lay eggs in oviposition pots lined with plaster of Paris. Observations were made on time taken by each sand fly species to lay eggs and the number of eggs laid per female. After 10 days, the eggs were harvested and placed into new pots for hatching. The hatching rate was recorded and analyzed. These two species of flies showed marked differences in their reproductive and survival strategy. L. longipalpis females laid eggs at a higher rate and appeared to have a shorter life cycle than P. duboscqi females . Supported by NIH 2T34GM008411