Eastern Equine Encephalitis is maintained in which ecological cycle and by which mosquito species?

• A. Maintained in bird cycle by Culiseta melanura
• B. Found along Atlantic & Gulf coasts
• C. Vaccines available for humans
• D. Primary vector: Aedes aegypti

Answer: (A)

Eastern Equine Encephalitis is kept in an enzootic bird–mosquito cycle, with the virus circulating primarily among birds. The mosquito that maintains this cycle is Culiseta melanura, which breeds in swampy, wooded areas and feeds mainly on birds, enabling the virus to persist in nature. Humans and horses can be infected only incidentally when a mosquito that bites an infected bird also bites a mammal, but they are not part of the ongoing maintenance cycle. The other options describe distribution, vaccine status, or a different mosquito not responsible for maintaining the enzootic cycle, so the bird cycle maintained by Culiseta melanura is the best answer.