Insect migration is the mass movement of insects, usually in search of more appropriate conditions. The malaria mosquito, genus按蚊，，，，is not thought to be a migratory insect: generally, it doesn’t travel (‘disperse’) more than about five km, and long-range movements that have been recorded are thought to be ‘accidental’ and un-important in terms of the movement of disease.按蚊are weak fliers, and any long-distance dispersal would need to be assisted – i.e., wind-aided dispersion. However, in other weak-flying insects, it has been suggested that wind-aided dispersion is governed by changes in the insect’s pattern of activity, perhaps due to physiological mechanisms set in motion in response to particular environmental cues. Therefore, to an extent at least, under the insect’s control.

Mosquitoesrequire an aquatic habitat用于幼虫的发展。因此，令人惊讶的是，在一年中多个月的地表水，蚊子种群以及相关疾病的区域中，雨季开始时会涌现。

这萨赫尔is a semi-arid region stretching east to west across the south-central regions of North Africa. Malaria transmission in the Sahel deceases markedly during the (3 – 8 -month) dry season, in which the mosquito vectors are not present. The reappearance of mosquitoes alongside the rains is currently attributed to mosquito夏眠（（particularly一个。coluzzii），，，，or long-distance migration from regions with year-round larval habitats (一个。冈比亚sensu strictu和一个。arabiensis）。尽管已经记录了蚊子的散布（这里称为“移民”），但最近的研究Huestis及其同事indicates that migration of malaria mosquitoes may be of greater significance than previously appreciated.

为了采样迁移的蚊子，选择了马里萨赫勒的四个村庄，从大型氦气的气球上悬挂着粘性的昆虫网状陷阱，向空中发射了氦气（图1）。通过一块巨大的混凝土块将其固定在地面上，绳索连接到重新组合的花园软管卷轴上，将其上下固定，然后将昆虫陷阱连接到气球的绳索上，以在三个高度（最初为40，40）处采样120和160;然后在地面上方90、120和190 m。后来增加了240和290 m处的另外两个站。这些陷阱是大型矩形（3×1 m）的网眼，上面涂有昆虫胶，气球在2013年至2015年之间每月连续大约10个夜晚（总共617夜）送出了大约10个夜晚。

总共十种按蚊- 疟疾蚊子被捕。其中包括主要的疟疾媒介一个。coluzziiand一个。冈比亚s. s.，以及次要重要性的向量（一个。pharoensis，，，，一个。coustani，，，，一个。squamousand一个。Rufipes）和三个不确定的一个。species. A total of 235 anopheline mosquitoes was caught. Although this total is relatively low (total number of the five most-captured anophelines:一个。squamosus，100;一个。pharoensis，40;一个。coustani，，，，30;一个。Rufipes，，，，24;一个。coluzzii，，，，23), when modelling the number of mosquitoes predicted to cross a 100-km line linking the sampling sites (perpendicular to the prevailing wind direction), the annual migration figures are impressive: more than 80,000一个。冈比亚，，，，6 million一个。coluzzii和4400万一个。squamosus单独的蚊子。

Among captured anophelines, the majority were female (4:1), and more than 90 % of these had previously taken a bloodmeal (i.e. were blood-fed, or the bloodmeal-dependent development of eggs could be seen [gravid/semi-gravid]). These findings highlight the significance of the captured mosquitoes in terms of disease transmission – although none were found to harbour the malaria parasite (all anophelines were tested), it is probably a sample size issue. That they were blood-fed indicates they could have been exposed to infection. Assuming aPlasmodium（（Pl.）infection rate of 1 % across all anophelines, there was a possibility of seeing only 2.35 infected mosquitoes. Using aPl.infection rate of 1 % for一个。coluzzii，，，，一个。冈比亚，，，，一个。coustaniand一个。pharoensis,另一个（已知）为0.1％按蚊作者计算出的物种，每年，每年高度，超过286,000个受感染的移民蚊子将越过其100公里的线。

使用最准确的气象数据可用，作者随后对所有捕获的截骨线的2小时和9小时飞行轨迹进行了建模，从而揭示了蚊子的可能起源以及估计的夜间距离（图3）。对于9小时的夜间飞行，所有样本量超过20种昆虫的隔离线物种的最大距离（“流离失所”）为257 - 295 km。此外，2/9小时飞行的平均距离分别为30公里和120公里（最大值为70和295 km）。大多数预测给出了西南蚊子的起源，该蚊子与峰值迁移时间的盛行风向有关（图2B）。

考虑到大量预测的年度迁移按蚊，因此，这些有趣的发现对疾病控制具有相当大的意义。当我们推动某些地区消除疟疾时，可能通过Pl.-infected mosquito vectors may present a bigger threat than previously understood. It may be that figuring out – and then controlling – possible sources of immigrating mosquitoes, by modelling meteorological data and not-too-distant vector populations, could considerably aid in the drive to elimination.