Concerns Intensify Over Mosquito And West Nile Virus Activity In North Sacramento County

July 5, 2013


Contact: Luz Maria Rodriguez, Public Information Officer
Office: 916.405.2082 | Cell: 916.416.6337


–Aerial spraying is being considered next week

Elk Grove, Calif.— The Sacramento-Yolo Mosquito and Vector Control District continues to closely monitor West Nile virus activity throughout Sacramento and Yolo counties. While activity is widespread, of specific concern is an area in north Sacramento County where over the last couple of weeks, virus activity has increased with the finding of many positive dead birds and multiple infected mosquito samples. “We’re concerned about the high infection rates and are considering aerial spraying” said David Brown, District Manager. Though no formal decisions have been made, aerial treatments to reduce adult mosquito populations may be necessary early next week. Laboratory surveillance results that will be available on Monday will determine next steps in the response plan. The unusual summer rain of last week followed by the extremely hot temperatures of the past days increased the number of mosquitoes and elevated infection rates. “We know mosquitoes are infected and we need to do everything we can to ensure they will not become a public health threat” said Brown.

While WNV activity is very widespread, the area currently being evaluated for adult mosquito control treatment is approximately 25,000 acres of North Sacramento County, north of the American River. If aerial spraying becomes necessary a map of the specific area will be provided. The product(s) that could be used for the aerial spraying are a pyrethrin or naled. Both insecticides are registered for use in mosquito control by the Environmental Protection Agency and these product(s) have been successfully used in previous mosquito control applications.

The District will continue to monitor mosquito and virus activity in the area through widespread trapping and testing. If a decision is made to proceed with aerial treatments, media will be notified immediately so information can be disseminated to the public. Localized ground fogging in the area will continue as necessary.

To see a map of all West Nile virus activity to date visit Residents can subscribe to receive email notifications for mosquito treatments by zip code. To sign up, visit our website and go to Spray Notifications. Information for current treatments planned is also available on the District website.

2013 West Nile virus activity update:

Sacramento County: 18 dead birds and 58 mosquito samples have tested positive for West Nile virus to date. 1 human case has been reported by the California Department of Public Health.

Yolo County: 6 dead birds and 19 mosquito samples have tested positive for West Nile virus to date