ROLE OF MOSQUITO SALIVARY GLAND SECRETIONS ON BLOOD FEEDING BY CULICIDAE (O:DIPTERA)

Abstract

The role of mosquito salivary gland secretion on human blood feeding process among three mosquito species, namely Culex (Cx.) pipiens, Aedes (Ae.) caspius and Anopheles (An.) pharoensis was investigated. The obtained results showed that the salivary gland extract did not induce blood agglutination. The whole blood clotting time was not affected by the addition of salivary gland extract. Platelet aggregation of human platelet rich plasma was decreased by the addition of salivary gland extract. The platelet aggregation inhibition was more pronounced in An. pharoensis than in Ae. caspius and Cx. pipiens indicating the presence of apyrase enzyme in the three studied species with different activities being higher in case of An. pharoensis than in Ae. caspius and Cx. pipiens. The salivary gland extract of mosquito species did not affect the human blood clotting factors (prothrombin, partial thromboplastin and fibrinogen). Probing and engorgement time of An. pharoensis was less than that of Ae. caspius and Cx. pipiens, confirming the presence of apyrase activity, though in different degrees. The present study elucidates the role of mosquito salivary secretions in facilitating blood feeding, by keeping blood flowing during the blood meal. Parasites may thus profit in order to achieve increased transmission, which eventually lead to enhance the role of mosquitoes as diseases vectors and expose human to infection risk.