Which species are the vectors for West Nile Virus (WNV)?

• A. Cx. tarsalis, Cx. pipiens, Cx. stigmatosoma
• B. Ae. aegypti, Anopheles gambiae, Mansonia
• C. Cx. quinquefasciatus, Aedes albopictus, Culiseta
• D. Anopheles stephensi, Culex restuans, Aedes vexans

Answer: (A)

West Nile Virus relies on mosquitoes in the genus Culex to spread between birds and, occasionally, to humans. These Culex species are efficient feeders on birds, sit in habitats where the virus circulates in the avian reservoir, and have the right level of competence to transmit the virus to people when they bite. The three species listed—tarsalis, pipiens, and stigmatosoma—are well-documented vectors of WNV in various regions, so a set that includes these Culex mosquitoes represents the established vector group for West Nile Virus.

Other mosquito groups (Aedes and Anopheles) are key vectors for different diseases (Aedes for dengue, Zika, chikungunya; Anopheles for malaria), and while some Culiseta can play a role in certain areas, they are not the primary, well-established transmitters of West Nile Virus.