Grieco John P, Achee Nicole L, Roberts Donald R, Andre Richard G
Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4799, USA.
J Am Mosq Control Assoc. 2005 Sep;21(3):279-90. doi: 10.2987/8756-971X(2005)21[279:CSOTSO]2.0.CO;2.
In August of 2000, a comparative susceptibility study was conducted using 3 species of Anopheles mosquitoes from Belize, Central America, and a standard species used in laboratory infection studies, Anopheles stephensi. Test populations were fed human blood infected with cultured Plasmodium falciparum (NF-54 strain) parasites via a membrane feeder. The control species, An. stephensi, exhibited the highest infections, with 73.8% of dissected specimens positive for sporozoites in the salivary glands. The control species also showed heavier sporozoite loads; 74.0% of positive glands having greater than 200 sporozoites. Of species from Belize, Anopheles darlingi was the most susceptibile, e.g., 41.0% of salivary glands were positive, with more than 200 sporozoites per gland. Anopheles vestitipennis had a low salivary gland infection rate (9.3%) and a moderate number of sporozoites in glands (i.e., 85.7% containing 50-250 sporozoites). Anopheles albimanus was the least susceptible species to infection. No specimens of An. albimanus from the Golden Stream population developed sporozoites in the salivary glands, yet 20.7% of dissected specimens had positive midgut infections. The An. albimanus Buena Vista population showed similar results with only a 2.2% salivary gland infection rate and a 21.5% midgut infection rate. Oocysts in An. stephensi increased in size by 20% after day 10. Development peaked at day 12, with a mean oocyst diameter of 58 microm at onset of oocyst differentiation. Oocysts developed more slowly in An. vestitipennis until day 10. After day 10, there was a 53% increase in oocyst development over the previous 10 days. Oocyst differentiation was not observed until day 13 postfeed. As with An. vestitipennis, both populations of An. albimanus showed similar slow rates of oocyst development; however, no dramatic growth increase occurred after day 10. The oocysts in the Golden Stream population exhibited a cessation of growth after day 10, peaking at a mean of 30 microm. The Buena Vista population did not exhibit the same level of reduced oocyst development. A gradual increase in growth continued until days 13 and 14 (36.7 and 35.7 microm, respectively).
2000年8月，利用来自中美洲伯利兹的3种按蚊以及实验室感染研究中使用的标准物种斯蒂芬斯按蚊进行了一项比较易感性研究。测试种群通过膜饲器吸食感染了培养的恶性疟原虫（NF - 54株）寄生虫的人血。对照物种斯蒂芬斯按蚊感染率最高，73.8%的解剖标本唾液腺中疟原虫卵囊呈阳性。对照物种的卵囊负荷也更重；74.0%的阳性腺体含有超过200个卵囊。在来自伯利兹的物种中，达林按蚊最易感，例如，41.0%的唾液腺呈阳性，每个腺体有超过200个卵囊。饰须按蚊的唾液腺感染率较低（9.3%），腺体中的卵囊数量适中（即85.7%含有50 - 250个卵囊）。白线按蚊是最不易感染的物种。来自金溪种群的白线按蚊标本在唾液腺中未发育出卵囊，但20.7%的解剖标本中肠感染呈阳性。布埃纳维斯塔种群的白线按蚊结果相似，唾液腺感染率仅为2.2%，中肠感染率为21.5%。斯蒂芬斯按蚊的卵囊在第10天后大小增加了20%。发育在第12天达到峰值，卵囊分化开始时平均卵囊直径为58微米。饰须按蚊的卵囊在第10天前发育较慢。第10天后，卵囊发育比前10天增加了53%。直到喂食后第13天才观察到卵囊分化。与饰须按蚊一样，白线按蚊的两个种群卵囊发育速度都较慢；然而，第10天后没有出现显著的生长增加。金溪种群的卵囊在第10天后停止生长，平均峰值为30微米。布埃纳维斯塔种群没有表现出相同程度的卵囊发育减少。生长逐渐增加，一直持续到第13天和第14天（分别为36.7微米和35.7微米）。
