How Does It Spread?

Infected Mosquitoes. Most often, WNV is spread by the bite of an infected mosquito. Mosquitoes are WNV carriers that become infected when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals when they bite.

Transfusions, Transplants, and Mother-to-Child. In a very small number of cases, WNV also has been spread through blood transfusions, organ transplants, breastfeeding and even during pregnancy from mother to baby.

Not through touching. WNV is not spread through casual contact such as touching or kissing a person with the virus.


Guidance for Clinicians
Statistics & Surveillance
WNV - What You Need to Know
California Information about WNV
Centers for Disease Control and Prevention (CDC) Links

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