Yellow fever as well as larvae-eating fish and copepods, which reduce the number of larvae. For many years, copepods of the genus "Mesocyclops" have been used in Vietnam for preventing dengue fever. It eradicated the mosquito vector in several areas. Similar efforts may be effective against yellow fever. Pyriproxyfen is recommended as a chemical larvicide, mainly because it is safe for humans and effective even in small doses. The second strategy is to reduce populations of the adult yellow fever mosquito. Lethal ovitraps can reduce "Aedes" populations, but with a decreased amount of pesticide because it targets the mosquitoes directly. Curtains and
Yellow fever viruses. The main vector ("A. aegypti") also occurs in tropical and subtropical regions of Asia, the Pacific, and Australia, but yellow fever has never occurred there, until jet travel introduced 11 cases from the 2016 Angola and DR Congo yellow fever outbreak in Africa. Proposed explanations include: But none is considered satisfactory. Another proposal is the absence of a slave trade to Asia on the scale of that to the Americas. The trans-Atlantic slave trade probably introduced yellow fever into the Western Hemisphere from Africa. The evolutionary origins of yellow fever most likely lie in Africa, with transmission of the