Learn more about WNV
To learn about WNV in humans in LA County,
To read more about WNV statewide, visit
Where does this
data come from?
Members of the public report dead birds and to
various agencies in LA County and in California.
Each dead bird is tracked, even when they cannot
be tested for WNV. The
Veterinary Public Health Program graphs and maps
the LA County data from all participating
agencies and shares it on this page.
The dead bird testing effort has been in
operation since 2004, the year after the virus
first appeared in LA County. It has helped
reveal shifts in the environmental epidemiology
of the virus over the years. Testing was
significantly decreased in mid-2013, and began
to increase again in 2015. A vibrant dead bird
testing program is an essential part of tracking
the virus in our environment in LA County.
Public Health has made reasonable efforts to provide accurate translation. However, no computerized translation is perfect and is not intended to replace traditional translation methods. If questions arise concerning the accuracy of the information, please refer to the English edition of the website, which is the official version.