West Nile Virus Transmission Cycle
  1. Transmission Process
  2. Signs & Symptoms
  3. Risk Groups
  4. Yard Protection
  5. Personal Protection
  6. Mosquito Repellents

Transmission Process

The female Culex mosquitoes become infected when they feed on infected birds, which may circulate the virus in their blood for a few days. Infected mosquitoes can then transmit the virus to humans and animals while feeding on blood. The virus is located in the mosquito's salivary glands. During blood feeding, the virus may be injected into the animal or human, where it may multiply, possibly causing illness.