Not only is West Nile Virus prevalent in the USA, but also Dengue Fever is making inroads.
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Tucson, Ariz., and Key West, Fla., each have had sustained populations of Aedes aegypti, a dengue-carrying mosquito, for some 20 years. And yet, whereas the virus rippled through southern Florida, documented cases in Tucson are still unknown. The interest is not just academic—answers could help avert future bouts of the virus. Right now, with no vaccine against the virus, the best defense available is reducing mosquito habitat in areas where dengue fever is common.
...Overall, dengue is challenging to combat. Bed nets, for example, a key tool when it comes to malaria prevention, are relatively useless against dengue, even though in both cases the vector is mosquitoes. The difference is bite timing. Whereas malarial mosquitoes feed at night (when nets around sleeping space are useful), the dengue-carrying variety typically feed during the two post-dawn hours and the two hours before sunset, Hayden says. As for therapy, it’s basically limited to painkillers. ...