Transmission

人类疟疾完全由按蚊传播。在南部非洲，这些病媒物种中最重要的是An。arabiensis、阿拉伯隐翅虫An. gambiae和An. funestus，与一个。具有更广的分布范围和更大的生态和生物可塑性。这些病媒的相对分布和丰度在生态和地理上各不相同。本提案所针对的研究地点不仅反映了疟疾传播生物学和强度的差异，而且还反映了影响这些病媒差异的生态差异。传播生物学在很大程度上受到蚊子行为及其对以蚊子为基础的控制措施（如驱虫蚊帐）的反应的影响。经杀虫剂处理过的蚊帐广泛分布在南非各地，是一项巨大的投资。经杀虫剂处理过的蚊帐不仅为蚊子提供了物理屏障，而且众所周知，经杀虫剂处理过的蚊帐具有驱虫作用，鼓励蚊子以其他宿主为食。然而，在南部非洲的一些地区，尽管分发和使用了驱虫蚊帐，蚊子仍然几乎完全以人类宿主为目标。西非最近的数据表明，在某些地区，驱虫蚊帐的驱虫效果（通常是使用驱虫蚊帐产生的）失效，具有抗药性的蚊子并没有因此而停止吸食人血。因此，了解生物学、觅食行为、杀虫剂抗性水平以及种群遗传学和分布对于指导南部非洲区域选择和实施有效和适当的疟疾干预措施是不可或缺的。目的1）了解三个研究点疟疾媒介生物学特性和昆虫学接种率。 描述南部非洲疟疾病媒种群的群落结构，并进一步描述南部非洲阿拉伯按蚊的摄食和休息行为。目的2）调查所有三个现场的病媒种群对杀虫剂的敏感性，并确定抗药性的机制。目的3）利用单核苷酸多态性（SNP）标记对阿拉伯按蚊种群进行遗传分析。

Human malaria is exclusively vectored by anopheline mosquitoes. In southern Africa the most important of these vector species are An. arabiensis, An. gambiae, and An. funestus, with An. arabiensis having a wider range and considerably greater ecological and biological plasticity. The relative distribution and abundance of these vectors vary ecologically and geographically. The study sites targeted in this proposal not only reflect differences in malaria transmission biology and intensity, but also ecological differences that affect these vector differences. Transmission biology is largely affected by mosquito behavior and their response to mosquito-based control measures such as insecticide-treated bed nets (ITNs). ITNs are widely distributed throughout south Africa and represent an enormous investment. ITNs not only provide a physical barrier to mosquitoes, but it is also well known that ITNs repel insects, encouraging mosquitoes to feed on alternative hosts. In some areas of southern Africa, however, mosquitoes have continued to almost exclusively target human hosts, despite the distribution and use of ITNs. Recent data from West Africa have shown that in some areas the repellency, typically induced by ITN use, fails and resistant mosquitoes are not deterred from taking human blood meals. Therefore, understanding the bionomics, foraging behavior, levels of insecticide resistance and population genetics and distribution are integral for guiding selection and implementation of effective and appropriate malaria interventions within the southern African region. Aim 1) Characterize the bionomics and entomological inoculation rates (EIR) of malaria vectors in each of the three study sites. Characterize the community structure of malaria vector populations in southern Africa and further characterize the feeding and resting behavior of Anopheles arabiensis in southern Africa. Aim 2) Survey insecticide susceptibility of vector populations at all three field sites and to determine the mechanisms of insecticide resistance. Aim 3) Conduct population genetic analysis of Anopheles arabiensis populations using single-nucleotide polymorphism (SNP) markers.