Which two mosquito species are primarily responsible for transmitting dengue virus?

• A. Culex quinquefasciatus and Anopheles gambiae
• B. Aedes vexans and Aedes polynesiensis
• C. Aedes aegypti and Culex quinquefasciatus
• D. Aedes aegypti and Aedes albopictus

Answer: (D)

Dengue virus is spread mainly by Aedes mosquitoes that breed in standing water around human habitations and bite during the day. Aedes aegypti is the principal urban vector worldwide because it thrives in close contact with people, feeds predominantly on humans, and reproduces in artificial containers. Aedes albopictus acts as a major secondary vector in many regions, expanding transmission into peri-urban and temperate areas and helping sustain dengue where aegypti is present. Other mosquito species listed are more associated with transmitting different diseases or have limited role in dengue transmission, so the combination of these two Aedes species best explains the primary dengue vectors.