Which organism is a vector for West Nile Virus?

The Culex mosquito is the primary vector responsible for the transmission of West Nile Virus. This virus typically circulates between birds and mosquitoes, with the Culex species serving a pivotal role in the cycle. When Culex mosquitoes bite infected birds, they can acquire the virus. Subsequently, when these mosquitoes bite humans or other animals, they can transmit the virus, leading to potential illnesses associated with West Nile Virus.

Other mosquito species, such as Aedes and Anopheles, are known for transmitting different diseases. For instance, Aedes mosquitoes are recognized vectors for dengue fever, Zika virus, and chikungunya, while Anopheles is primarily associated with malaria transmission. Stegomyia, now often included under Aedes, is also linked to similar viruses as Aedes mosquitos. Thus, they do not play a significant role in West Nile Virus transmission, highlighting why Culex is distinctively the correct answer.