Concerns Grow Over Widespread West Nile Virus Activity Throughout Sacramento County


June 27, 2012


–Additional aerial treatments may be necessary 

View an image of the area of concern

Elk Grove,Calif.— The Sacramento-Yolo Mosquito and Vector Control District continues to closely monitor the spread of West Nile Virus activity as many new dead birds and mosquito samples test positive for the disease and activity is now widespread throughout Sacramento County. “We are continuing to see significant West Nile virus activity” said David Brown, District Manager. “We need to act rapidly in order to reduce infected mosquito populations and protect public health” he added. The District is considering expanding aerial spraying to reduce populations of infected mosquitoes. In the meantime, cooperation from the public to drain any stagnant water from their property and protect themselves from bites by using a mosquito repellent is critical.

The areas where the majority of activity is concentrated include portions of Sacramento County south of the American River down to the Elk Grove area.  In addition, the area around North Highlands is also currently seeing an increase of dead birds and mosquito samples that have tested positive for the disease. “Our bird populations continue to have high infection rates and they are infecting the mosquitoes allowing for the virus to amplify” indicated Brown.

While most of the activity is currently concentrated in Sacramento County, the virus has also been detected in areas of Yolo County including West Sacramento and Davis.

For a location of the areas being considered for aerial applications, please refer to the attached map and visit . Please note that the area can be modified based on ongoing surveillance results. If aerial spraying becomes necessary, they will be made using either a pyrethroid or an organophosphate insecticide registered for use in mosquito control by the US Environmental Protection Agency (EPA) and California EPA.

Residents can subscribe to receive email notifications for mosquito treatments by zip code. To sign up, visit  and go to Spray Notifications. Information for current treatments planned is also available on the District website under Spraying Updates.


2012 West Nile virus activity update:

Level 2–Sacramento County: 135 dead birds, 0 sentinel chickens, 124 mosquito samples have tested positive for West Nile virus to date.

Level 2–Yolo County:  4 dead birds, 0 sentinel chicken, 4 mosquito sample have tested positive for West Nile virus to date

            Contact: Luz Maria Rodriguez, Public Information Officer

Office:  916.405.2082 | Cell:  916.416.6337