Why do female Aedes aegypti (Diptera: Culicidae) feed preferentially and frequently on human blood?
Why do female Aedes aegypti (Diptera: Culicidae) feed preferentially and frequently on human blood?
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DOI：
10.1603/0022-2585-38.3.411
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发表时间：
2001-05-01
影响因子：
2.1
通讯作者：
Scott, TW
中科院分区：
文献类型：
--
作者：
Harrington, LC;Edman, JD;Scott, TW
埃及伊蚊（Aedes aegypti（L.）），登革热和黄热病病毒的传播媒介。喜欢吸食人血，并且倾向于放弃吸食糖。这一观察结果挑战了蚊子生物学的两个原则：ii）蚊子吸收植物碳水化合物用于合成能量储备和血液用于繁殖，以及（2）与其他物种的血液相比，当蚊子以人类血液为食时，产卵量减少。人体血液中氨基酸异亮氨酸（特别是血浆中的游离异亮氨酸）的次优量被认为是人体血液摄入时卵子产量降低的原因。我们测试了这样一个假设，即以人血为食与Ae的选择优势有关。埃及伊蚊，是这种蚊子与人类密切和流行病学上重要关系的根本原因。我们的五个实验研究了不同异亮氨酸浓度对积累的能量储备，宿主接触频率，存活率和产卵量的影响。当蚊子在7到10天的时间里吸食血食，而不喂糖时。增加异亮氨酸浓度降低能量储备，并且不增加产蛋量。与高异亮氨酸的小鼠宿主相比，埃及伊蚊每天以低异亮氨酸的人类宿主为食时，所采取的血餐较小但更频繁。以前的报道说，异亮氨酸提高鸡蛋生产得到证实，只有当女性被喂食糖，一个不寻常的行为，大多数国内Ae。埃及人。喂食人血和水的雌性比喂食人血加糖或富含异亮氨酸的小鼠血液（有或没有糖）的队列具有更高的年龄特异性生存率（l（x）），生殖输出（m（x））和累积净替代（R-0）。人类血液中独特的异亮氨酸浓度与埃及伊蚊的不寻常倾向有关，埃及伊蚊优先和频繁地以人类为食，这种行为增加了这种蚊子的适应性。合成能量储备，并与人类宿主接触，使其成为人类病原体的特别有效的传播者。
Adult female Aedes aegypti (L.), the vector of dengue and yellow fever viruses. have an affinity for feeding on human blood and a tendency to forego feeding on sugar. This observation challenges two tenets of mosquito biology: ii) mosquitoes imbibe plant carbohydrates for synthesis of energy reserves and blood for reproduction and (2) egg production is reduced when mosquitoes feed on human blood compared with blood from other species. Sub-optimal amounts of the amino acid isoleucine in human blood (particularly free isoleucine in plasma) are thought to be responsible for lowered egg production when human blood is ingested. We tested the hypothesis that feeding on human blood is associated with a selective advantage for Ae. aegypti and is an underlying reason for this mosquito's intimate and epidemiologically important relationship with human beings. Our five experiments examined the effects of different isoleucine concentrations on accumulated energy reserves, frequency of host contact, survival, and egg production. When mosquitoes imbibed blood meals over a 7- to 10-d period and were not fed sugar. increased isoleucine concentration decreased energy reserves and did not increase egg production. Aedes aegypti took smaller but more frequent blood meals when feeding on a low-isoleucine human host daily compared with a high-isoleucine mouse host. Previous reports that isoleucine enhances egg production were confirmed only when females were fed sugar, an unusual behavior for most domestic Ae. aegypti populations. Females fed human blood and water had greater age-specific survival (l(x)), reproductive output (m(x)), and cumulative net replacement (R-0) than cohorts fed human blood plus sugar or isoleucine-rich mouse blood with or without access to sugar. The unique isoleucine concentration of human blood is associated with Ae, aegypti's unusual propensity to feed preferentially and frequently on humans-a behavior that increases this mosquito's fitness. synthesis of energy reserves, and contact with human hosts, making it an especially effective disseminator of human pathogens.