Effect of Leishmania spp infection on the survival,life expectancy,fecundity and fertility of Lutzomyia longipalpis s.l. and Lutzomyia pseudolongipalpis

We evaluated the effects of Leishmania spp infection on severalpopulation parameters of Lutzomyia longipalpis sensu latoandLutzomyia pseudolongipalpis, vectors of visceral leishmaniasisin Venezuela, under experimental conditions during the first post-feeding period.Females of both species were allowed to feed and engorge on a suspension of freshwashed human red blood cells in foetal calf serum. These blood cells were eithernon-infected or infected with one of the fourLeishmania spp strainsand were offered through a chicken skin membrane. The longevity, life expectancy andthe fecundity of uninfected flies were similar in both species, but the fertility wassignificantly lower in uninfected Lu. longipalpis females. In allcases, the infection of Lu. longipalpis and Lu.pseudolongipalpis by the Leishmania strains resulted insignificant detrimental effects, which exerted a fitness cost expressed by reducedsurvival and life expectancy, as well as decreased fertility and fecundity comparedwith the control groups. Nevertheless, differences in these parameters were observedbetween these vector species depending on whether they were infected with theautochthonous Venezuelan Leishmania infantum strain (NESA) or theBrazilian reference strain (PP75). The experimental data obtained agree with fielddata on the natural infection of these vector species and the significance of thisscenario is discussed.