Application of Polovodova's method for the determination of physiological age and relationship between the level of parity and infectivity of Plasmodium falciparum in Anopheles gambiae s.s,south-eastern Benin

Background: polovodova method based on counting follicular dilatations estimates the number of egg-laying in mosquitoes. however,some researchers doubt the reliability of this method because of the absence of multiple dilatations in vectors after many gonotrophic cycles. it is in this context of controversy that our study was carried out to evaluate the importance of follicular dilatations in the determination of parity levels in an. gambiae s.s. moreover,the application of this method allowed us to clarify the evolution of vectors' infectivity to p. falciparum according to their parity level. methods: we used two techniques to determine the parity level in an. gambiae s.s. we used two batches of wild strain mosquitoes reproduced after a known number of egg-laying in laboratory. the first batch was submitted to oil injection in the ovaries using a micropipette. in the same way,the classic technique of ovaries dilaceration (a technique based on the polovodova method) was applied to the second batch. in order to assess relationship between parity level and mosquitoes' infectivity,polovodova method was applied on vectors collected on humans. finally,heads and thoraces of these vectors were individually analyzed for p. falciparum antigen detection using an elisa assay. results: in the first batch including 50 female mosquitoes never laid