Ibrahim M S, Trpis M
Department of Immunology and Infectious Diseases, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, MD 21205.
Med Vet Entomol. 1987 Oct;1(4):329-37. doi: 10.1111/j.1365-2915.1987.tb00363.x.
Life table statistics were used to examine the survival functions of filarial susceptible and refractory species of the Aedes scutellaris (Walker) group of mosquitoes, following infection with high and moderate doses of Brugia pahangi (Buckley & Edeson). Survivorship curves and hazard function curves were generated, and the median survival times and the proportions of mosquitoes surviving beyond the extrinsic incubation period of the parasite were determined. In the susceptible populations of Aedes polynesiensis Marks, Ae. pseudoscutellaris (Theobald) and Ae.tabu Ramalingam & Belkin a dose-response relationship was detected between parasite load and mortality. This relationship was characterized by a significant reduction in the proportions of infected female mosquitoes surviving at days 1 and 9 postinfection, reduction in the median survival times and an increase in the hazard rates as the infectious dose increased. The survival of the refractory species, Ae.alcasidi Huang and Ae.katherinensis Woodhill was not significantly affected by the infection. A positive correlation between microfilaraemia in the vertebrate host and parasite load in the susceptible mosquito populations was also observed. Regression analysis of the number of parasites recovered from susceptible mosquitoes at the time of death showed that mosquitoes at highest risk of dying harboured from 11.6 to 19.4 infective larvae when fed on a gerbil with sixty-five microfilariae per 20 microliters blood; this resulted in 34.4-40.2% mortality by day 9 postinfection. A mean number of 32.6-46.9 infective larvae was observed when these populations were exposed to a gerbil with a microfilaraemia of 150 mf/20 microliters and resulted in 72.8% to 80% mortality in these populations. Viable infective larvae were recovered from infected mosquitoes up to 50 days postinfection.
使用生命表统计数据来研究感染高剂量和中等剂量彭亨布鲁线虫（Buckley & Edeson）后，斯氏伊蚊（Walker）组中对丝虫易感和难治的蚊虫种类的存活函数。生成了生存曲线和风险函数曲线，并确定了中位生存时间以及在寄生虫外在潜伏期之后存活的蚊虫比例。在波利尼西亚伊蚊Marks、伪斯氏伊蚊（Theobald）和塔布伊蚊Ramalingam & Belkin的易感种群中，检测到寄生虫负荷与死亡率之间存在剂量反应关系。这种关系的特征是，感染后第1天和第9天存活的受感染雌蚊比例显著降低，中位生存时间缩短，且随着感染剂量增加，风险率上升。难治性种类的存活，即阿尔卡西迪伊蚊Huang和凯瑟琳伊蚊Woodhill，未受到感染的显著影响。还观察到脊椎动物宿主中的微丝蚴血症与易感蚊虫种群中的寄生虫负荷之间存在正相关。对死亡时从易感蚊虫中回收的寄生虫数量进行回归分析表明，当以每20微升血液中有65条微丝蚴的沙鼠为食时，死亡风险最高的蚊虫体内携带11.6至19.4条感染性幼虫；这导致感染后第9天的死亡率为34.4 - 40.2%。当这些种群接触微丝蚴血症为150 mf/20微升的沙鼠时，观察到平均有32.6 - 46.9条感染性幼虫，这些种群的死亡率为72.8%至80%。在感染后长达50天的时间里，从受感染的蚊虫中回收了活的感染性幼虫。
