Data from: The microsporidian parasite Vavraia culicis as a potential late life-acting control agent of malaria

Microsporidian parasites are being considered as alternatives to conventional insecticides for malaria control. They should reduce malaria transmission by shortening the lifespan of female mosquitoes and thus killing them before they transmit malaria. As the parasite replicates throughout the mosquito’s life, it should have little detrimental effects on young mosquitoes, thus putting less selection pressure on the hosts to evolve resistance. Here we examined these expectations for the microsporidian Vavraia culicis on Anopheles gambiae Giles sensu stricto mosquitoes under varying environmental conditions. Infection by the microsporidian delayed pupation by 10%, decreased fecundity by 23% and reduced adult lifespan by 27%, with higher infectious doses causing greater effects. The decrease of the lifespan was mostly due to an increase of the mortality rate with age. Similarly, the parasite’s effect on mosquito fecundity increased with the mosquitoes’ age. Neither infection nor food availability affected juvenile survival. Thus, as V. culicis reduced the longevity of A. gambiae (s.s.), yet affected mortality and fecundity of the young mosquitoes only slightly, the microsporidian is a promising alternative to insecticides for effective malaria control that will impose little evolutionary pressure for resistance.

微孢子虫寄生虫（Microsporidian parasites）正被视作疟疾防控领域传统杀虫剂的潜在替代方案。这类寄生虫可通过缩短雌性蚊子的寿命，使其在具备传播疟疾能力前死亡，从而降低疟疾传播风险。由于该寄生虫可在蚊子的整个生命周期内增殖，因此对幼龄蚊子几乎无有害影响，进而降低了宿主进化出抗性的选择压力。本研究在不同环境条件下，以冈比亚按蚊狭义种（Anopheles gambiae Giles sensu stricto）为实验对象，检验了微孢子虫Vavraia culicis的上述预期效应。感染该微孢子虫可使蚊子化蛹时间推迟10%、繁殖力降低23%、成虫寿命缩短27%；且感染剂量越高，上述效应越显著。寿命缩短主要源于随蚊龄增长的死亡率升高。类似地，该寄生虫对蚊子繁殖力的影响亦随蚊龄增加而增强。感染与否与食物供给量均未对幼体存活率造成影响。综上，鉴于V. culicis可缩短冈比亚按蚊（狭义种）的寿命，且仅对幼龄蚊子的死亡率与繁殖力产生轻微影响，该微孢子虫是一种极具前景的杀虫剂替代方案，可实现高效疟疾防控，且几乎不会施加抗性进化的选择压力。