Concerns Intensify over Mosquito and West Nile Virus Activity in South Sacramento


July 9, 2010


–Aerial spraying may be necessary

Elk Grove, Calif.— The Sacramento-Yolo Mosquito and Vector Control District continues to closely monitor an area in South Sacramento for West Nile virus.  Over the last couple of weeks, virus activity has increased with the finding of positive dead birds and multiple infected mosquito samples. “We’re very concerned with 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. Late spring rains and sudden hot temperatures increased the number of mosquitoes and elevated infection rates. “We know there are mosquitoes that are already infected and we need to be proactive in making sure they will not be a public health threat” said Brown. Though mosquitoes might be coming from a variety of sources, there are many neglected swimming pools in the area that could be contributing to the problem.

The area being evaluated is approximately 29,000 acres of South Sacramento from Eldercreek down to Elk Grove Blvd and from Bruceville Rd. to Excelsior (download map as PDF, or see below). If aerial spraying becomes necessary, the product that would be used is Evergreen 60-6, an insecticide approved for use in mosquito control by the Environmental Protection Agency (and the product used in previous mosquito control applications). Since there is currently a worldwide shortage of this product and the District has a limited supply, if other spray missions are necessary, other registered pesticides may be considered.

  • Blue Markers: Dead Birds
  • Green Markers: Mosquito Traps

View the interactive map

The District will continue to monitor activity in the area through widespread mosquito 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. 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.

Contact: Luz Maria Rodriguez, Public Information Officer

Office: 916.405.2082 | Cell: 916.416.6337


2010  West Nile virus activity update:

Level  2–Sacramento County: 10 dead birds, 0 sentinel chickens, 18 mosquito samples have tested positive for West Nile virus to date.

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

Practice the District D’s of Mosquito Prevention:

DRAIN standing water that may produce mosquitoes.

DAWN and DUSK are times to avoid being outdoors.

DRESS appropriately be wearing long sleeves and pants when outside.

DEFEND yourself by using an effective insect repellent.  Make sure to follow label directions!

DOOR and window screens should be in good working condition.

DISTRICT personnel are also available to address any mosquito problems. Call them at 1-800-429-1022 or visit