2017 West Nile Virus Activity

The Sacramento-Yolo Mosquito and Vector Control District's ongoing surveillance program has detected West Nile virus activity in Sacramento or Yolo counties in 2017. Archived data is available for 2007 activity, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, and 2016.

For Human and Equine cases, please visit westnile.ca.gov.

West Nile virus positives total for 2017
Sentinel Animals000
Mosquito Samples112
Dead Birds10010

Click here for a map of these locations

Below you will find the breakdown of West Nile virus activity

Sentinel animals tested positive for West Nile virus:
TestedCountyCityZip Code

Mosquito Samples tested positive for West Nile virus:
CollectedCountyCityZip CodeSpecies (# of Mosquitoes in Trap)
06/08/2017SacramentoIsleton95641Cx pipiens (1)
06/08/2017YoloZamoraCx tarsalis (23)

Dead birds tested positive for West Nile virus:
CollectedCountyCityZip CodeSpecies
05/07/2017SacramentoFolsom95630Red-shouldered Hawk #17-280
05/22/2017SacramentoGalt95632Western Scrub-Jay #17-429
05/23/2017SacramentoSacramento95826American Crow #17-431
05/25/2017SacramentoSacramento95829Black Phoebe #17-471
05/26/2017SacramentoGalt95632Western Scrub-Jay #17-487
05/29/2017SacramentoCarmichael95608Western Scrub-Jay #17-552
06/01/2017SacramentoSacramento95826American Crow #17-590
06/03/2017SacramentoSacramento95826Yellow-billed Magpie #17-634
06/06/2017SacramentoSacramento95823House Finch #17-636
06/07/2017SacramentoRosemont95826Western Scrub-Jay #17-669

If you see a bird, particularly a crow or magpie, lacking signs of trauma that has been dead for less than 24 hours, please call 1-877-WNV-BIRD (1-877-968-2473) or report it online here. Crows and magpies are particularly susceptible to the disease, so they make excellent early warning sentinels for virus activity in our area.