The Placer Mosquito and Vector Control District confirmed the first mosquito sample to test positive for West Nile virus in the county for the 2021 season. The mosquitoes were collected in a mosquito trap in western Placer County near the Westpark neighborhood of Roseville. Residents are encouraged to use an EPA-registered repellent and dump and drain standing water on their property.
| Indicators | Placer County* | CA* |
|---|---|---|
| Human Cases/Fatal Cases | 1/0 | 46/4 |
| Dead Birds | 3 | 182 |
| Mosquito Samples | 63 | 2,032 |
| Horses | 0 | 8 |