Name the primary vector for transmitting West Nile virus.

The primary vector for transmitting West Nile virus is mosquitoes. This is because the life cycle of the virus involves an amplification host, which is typically birds, but mosquitoes are responsible for the transmission of the virus to humans and other animals. Mosquitoes become infected with the virus when they feed on the blood of infected birds, and then they can subsequently spread the virus when they bite other hosts.

While birds serve as the main reservoir, they do not directly transmit the virus to humans; instead, it is the mosquitoes that bridge the gap between the bird reservoir and mammals, including humans. Other vectors such as ticks and mice are not involved in the transmission of West Nile virus to humans, making mosquitoes the key players in the epidemiology of this disease. Hence, understanding the role of mosquitoes in the transmission cycle is crucial for disease prevention and control strategies regarding West Nile virus.