Increase in West Nile Activity Prompts Aerial Spraying over Portions of Yolo County


August 10, 2012 


–Spraying will occur mainly over agricultural areas and small rural communities

 View Aerial Treatment Map

Elk Grove, Calif.— The Sacramento-Yolo Mosquito and Vector Control District announced today that aerial treatment for adult mosquitoes that may carry the potentially fatal West Nile virus is scheduled for next week beginning Tuesday,  August 14 and finishing Wednesday August 15 (weather dependant).  The applications will occur from approximately 8:00 pm to midnight over portions of Yolo County.  “We continue to see increased West Nile virus activity and high infection rates throughout the area” said David Brown,  District Manager. “The activity is widespread and many birds and mosquitoes have tested positive for the disease. We need to act immediately to decrease the risk of human infections” added Brown. “With the warm summer weather many residents will be outdoors when mosquitoes are most active and we need to protect public health.”

The aerial applications will cover approximately 28,000 acres and will mainly occur over known agricultural sources; however it will include the communities of Knights Landing, Dunnigan and areas south of Woodland and north of Davis. For exact spraying locations please visit  Aerial treatments will be made using Trumpet, an organophosphate insecticide registered for mosquito control by the US Environmental Protection Agency (EPA) and California EPA and traditionally used to treat agricultural areas. While attempts are made to notify the public, the District may postpone or cancel a scheduled application due to unfavorable weather conditions or other reasons.  The District will also continue to conduct ground treatments to supplement these aerial applications.

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  3–Sacramento County:  356 dead birds, 13 sentinel chickens, 351 mosquito samples have tested positive for West Nile virus to date.

Level 3–Yolo County:  35 dead birds, 2 sentinel chickens, 48 mosquito samples have tested positive forWest Nile virus to date.


            Contact: Luz Maria Rodriguez, Public Information Officer

Office:  916.405.2082 | Cell:  916.416.6337