Information for Health Departments and Districts

Dead bird and mosquito testing are no longer provided free of charge, although a few counties are still doing some limited testing either through Environmental Health or through mosquito control.

Mosquito Surveillance

Surveillance for mosquitoes provides information on species type and population. Positive mosquitoes indicate risk of West Nile virus is increasing, but even increases in Culex species populations can indicate a higher risk of disease locally.

Dead Bird Surveillance

Dead bird surveillance provides general information about when and where West Nile Virus is present in an area. Monitoring and mapping dead bird calls provides a means of determining where virus transmission may be occurring and presents an opportunity to educate callers about reducing their risk for arboviral diseases.

Download this pdf file.Guidance for West Nile Virus Surveillance

Download this pdf file.Status of West Nile Virus 2001-2019

Page last update 04/17/2020