在美国，六月的最后一周被称为National Mosquito Control Awareness Week, or simply “Mosquito Week”, as declared by the American Mosquito Control Association. While mosquito season is only starting for this year in the US, we already had 10 human cases so far this year. Why should we pay attention to this and to mosquito control in general?

Mosquitoes are the最致命的动物on the planet, responsible for 830,000 lost lives per year through their bites. Being微虫，他们不会仅仅通过他们的叮咬, but indirectly through the variety ofpathogensthey transmit, ranging from viruses, bacteria, protozoans and even worms. The most common of these microorganisms pose a considerable amount ofglobal health burden，以Disability Adjusted Life Yearsof the diseases they cause globally. For example, 216 million cases of疟疾在2016年全球发生，而3.9亿箱denguewere estimated to occur in 2013. While we mostly associate mosquitoes with tropical diseases such as above, they also transmit diseases of public health importance at temperate latitudes, such as西尼罗河病毒(WNV),东部马脑炎病毒, and many others. Finally, there is something psychologically disturbing about knowing that flying insects that bite us can transmit pathogens that can make us sick, promoting our awareness.

Most mosquito-borne diseases (with some notableexceptions) do not have specific therapeutics or vaccines, and therefore their control and prevention relies on the control of their mosquito vectors. Traditionally, this has been done mostly using insecticides that target adult flying mosquitoes (adulticides). While now we know that this method generally only has ashort-term和limited effect on mosquito population size, it is an important method in emergency circumstances, such as the large西尼罗河病毒outbreak in Texas in 2012. It is also an important method in the case of室内残留喷涂within homes for malaria control in sub-Saharan Africa. In contrast, compounds that target larval mosquitoes within breeding sites (larvicides) such asBtiusually have a longer-term, more sustainable effect on mosquito populations, and tend to have less detrimental effects on non-target organisms. Most importantly, these and the many other available methods to control mosquitoes need to be used synergistically in anIntegrated Vector Managementframework, similar to the method ofIntegrated Pest Managementapplied for agricultural and residential pests.

The most important aspect of such an Integrated Vector Management framework is a clear focus on the ecology and evolution of the target mosquito vector species, and their actual “control” is the smallest part of the job. Each mosquito-borne disease (be it疟疾,dengue,西尼罗河病毒或者EEE）有一个潜在的蚊子物种列表，这些物种是该特定病原体的合格载体。这些特定物种需要通过蚊子监测来监测和测试感兴趣的病原体。这涉及设置和检索蚊子陷阱（例如CDC light-traps或者gravid traps), sorting and identifying the collected mosquito specimens to species, and testing the vector species for pathogens.

所有这些都需要在人力，运输，专业知识和实验室能力上进行大量投资和资金。例如，就我而言，我在夏季环境中每周两次花几个小时，然后检索2至3个陷阱，然后将它们运送到Washington Department of Health Zoonotic Disease Program, who then sort, identify and test them. This is the same for many other surveillance partners across Washington State, as well as at the Mosquito Control Districts, and across many other States. We do all this so that we can detect changes in mosquito populations and the risk of West Nile virus infection before we start to get equine and human WNV cases.

Even when trying to decide where to set up mosquito traps for surveillance, it is important to consider the ecology of mosquito vectors. For example,Culex pipiens, one of main vectors of West Nile virus, is known to be associated withurban environments, specifically with culverts and catch basins. There is also evidence that productive breeding sites and disease transmission risk can be associated with certainland-cover types和socio-economic conditions, such asurbanization和poverty，缺乏可访问的potted water. However, there is still limited information on the relationship between the characteristics of breeding sites and their productivity for specific mosquito vectors. For example, we know that large outside drums which residents use to store rainwater in the tropics aremajor breeding sitesforAedes aegypti，登革热，Zika，Chikungunya和许多其他病毒的媒介。但是，当我们看一个带有各种小物体收集水的后院混乱时，很难确定哪种潜在的繁殖地点更为重要。不管，reducing these sourcesof mosquito production would be the most important way to control mosquito vectors.

In addition to the ecology of mosquito vectors, the evolution of the mosquitoes as well as the pathogens is also important to consider and monitor as part of mosquito control programs. Mosquito vectors do have the ability to developresistanceto the insecticides used to control them, especially if they have been used for long-term indiscriminately. In fact, this iswhat happenedin the 1960s to DDT, which led to the failure of the eradication campaign of malaria in Africa. Therefore, insecticide resistance needs to be monitored to ensure that mosquito control remains effective. This is most frequently practiced in Africa where疟疾mosquito controlprograms routinely test mosquitoes for insecticide resistance. Finally, pathogens can also evolve resistance to therapeutics, such as howPlasmodium falciparumdeveloped and continues to develop对抗疟疾的抗性.

While the specific ecology and evolution of mosquito vectors can create challenges for mosquito control programs, it also creates opportunities for novel treatment methods. For example, genetically modified mosquitoes such as those developed byOxitecare effective to reduce populations because of the specific property of femaleAedes aegyptithat they only mate once in their lifetime. Similarly,autocidal gravid ovitrapsthat lure adult femaleAedes aegyptimosquitoes rely on their behavior ofskip oviposition，将鸡蛋放在许多不同的繁殖地点，并运输杀死幼虫的化合物，使其有效性增加。

These intricacies and complications of mosquito and mosquito-borne disease ecology make their control a highly complex and expensive enterprise. Typically, mosquito surveillance and control is the范围of local, regional or state government. In areas wheremosquito control districts在操作中，这些活动具有当地税收和费用稳定的资金。但是，在其他领域，蚊子控制和监视必须以有限的预算作为当地卫生部门的一部分。通常，当预算紧张时，first thing that goesis local mosquito surveillance and control. This enterprise also shares the curse of success with local health in that it only gets attention when there is a problem – when everything goes well, the lack of mosquitoes and disease gets taken for granted, and therefore looked at as an unnecessary expenditure. Once mosquito surveillance and control is lost, it is very difficult to regain the lost physical and intellectual infrastructure. This leads to amosaic patchworkof coverage of mosquito control and surveillance across the United States, with some areas (such asCalifornia) having an extensive, professional system, while others are serviced by a single person with a spray truck that only responds to nuisance mosquito calls. Such a patchwork isill-equipedto detect and respond to novel emerging mosquito-borne diseases (such as Zika virus) or changes in the ecology or evolution of endemic pathogens (see e.g. the2012 West Nile virus outbreak). Mosquito surveillance and control costs iscapableof protecting citizens from diseases that can kill and disable them at afraction of the expense照顾患者，是good investment.

If you had any doubts about the value of mosquito surveillance and control, I do hope that I convinced you that it is a well-spent expense! If you know someone in a position of deciding on funding for your local mosquito surveillance and control program, please share this article with them – thanks!