Ferguson Heather M, Gouagna Louis C, Obare Peter, Read Andrew F, Babiker Hamza, Githure John, Beier John C
Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, UK.
Am J Trop Med Hyg. 2005 Aug;73(2):312-20.
We conducted a field study in an area of endemic malaria transmission in western Kenya to determine whether mosquitoes that feed on gametocyte-infected blood but do not become infected have reduced or enhanced fecundity in comparison to mosquitoes fed on uninfected blood. Fifteen paired membrane-feeding experiments were conducted in which two strains of Anopheles gambiae mosquitoes were simultaneously fed on either Plasmodium falciparum-infected blood from children or uninfected control blood from adults. The presence of noninfecting gametocytes in blood increased the probability that An. gambiae would produce eggs after one blood meal by sixfold (odds ratio for control relative to infected blood group 0.16; 95% CI 0.10-0.23). This result could not be explained by variation in blood meal size or hemoglobin content between hosts. When children cleared their infections, the difference in gravidity between mosquitoes fed on their blood and uninfected adults disappeared, suggesting this phenomenon is due to the presence of Plasmodium gametocytes in blood and not to host-specific factors such as age. This result was observed in two mosquito strains that differ in their innate fecundity, suggesting it may apply generally. To our knowledge, this is the first time that Plasmodium has been implicated as enhancing vector gravidity.
我们在肯尼亚西部疟疾流行传播地区开展了一项实地研究，以确定吸食感染配子体血液但未被感染的蚊子与吸食未感染血液的蚊子相比，其繁殖力是降低还是增强。我们进行了15组配对膜饲实验，让两株冈比亚按蚊同时吸食来自儿童的感染恶性疟原虫的血液或来自成年人的未感染对照血液。血液中存在非感染性配子体，使冈比亚按蚊在一次血餐后产卵的概率增加了6倍（对照相对于感染血液组的优势比为0.16；95%置信区间为0.10 - 0.23）。这一结果无法用宿主间血餐大小或血红蛋白含量的差异来解释。当儿童清除感染后，吸食他们血液的蚊子与未感染成年人的蚊子在妊娠率上的差异消失了，这表明这种现象是由于血液中存在疟原虫配子体，而非年龄等宿主特异性因素。在两种先天繁殖力不同的蚊子品系中都观察到了这一结果，表明这可能具有普遍适用性。据我们所知，这是首次发现疟原虫与提高媒介妊娠率有关。
