West Nile virus Facts
- West Nile virus is the most common mosquito-borne disease that affect residents in Los Angeles County
- Public health agencies detect West Nile virus every year in L.A. County. This means the virus is found naturally in our city environments, which means it's endemic.
- Our agency uses routine traps to colect samples of mosquitoes. The mosquito samples are tested for a mosquito-borne diseases, such as West Nile virus. In addition, dead birds, which can carry West Nile virus, are submitted for testing.
2022 West Nile Virus Activity
Last update: 10/3/22
West Nile Virus Positive Mosquito Samples
A sample is a random collection of 10-50 mosquitoes from a trap. Positive mosquito samples from routine and randomized trapping provide insight into of the spread of West Nile virus.
|City/Community||Number of WNV+ Mosquito Samples||Date of first report|
|Altadena (LA County)||1||9/12|
|East San Gabriel (LA County)||9||7/11|
|South Monrovia Island (LA County)||2||8/8|
|West Valinda/Bassett (LA County)||11||7/25|
West Nile Virus Positive Dead Birds
People report dead birds they observe in their community. Positive dead birds are an indication West Nile virus is widespread in the region.
|City/Community||Number of WNV+ dead birds||Date of first report|