West Nile virus was detected in Contra Costa County, the Contra Costa Mosquito and Vector Management District mentioned Monday.
The district mentioned a California scrub jay in San Ramon examined constructive for the pathogen — the primary hen within the county to check constructive for West Nile virus this yr, although each Alameda and Santa Clara counties have additionally reported contaminated birds in 2025.
The district mentioned contaminated birds are sometimes the primary signal of West Nile virus in Contra Costa County.
In keeping with the U.S. Facilities for Illness Management and Prevention, West Nile virus is the main explanation for mosquito-borne illness in the US. Mosquitoes can unfold the virus to people after feeding on birds that carry the contagion.
There aren’t any vaccines to forestall or medicines to deal with West Nile in folks, the CDC mentioned, however most contaminated folks don’t really feel sick and solely about 1 in 5 folks develop a fever and different signs, together with headache, physique aches, vomiting, diarrhea or rash.
In keeping with the CDC, solely about 1 out of 150 contaminated folks develop a critical, typically deadly, sickness. Folks older than age 60 and people with weakened immune programs usually tend to get significantly sick, the California Division of Public Well being warns.
There have been three human instances of West Nile virus in California this yr, with one deadly case, the state public well being division mentioned. There have been 132 human instances in 2024, 12 of which had been deadly.
The Contra Costa Mosquito and Vector Management District suggested residents to dump out standing water — the place mosquitoes lay their eggs — no less than as soon as per week to cut back the chance of mosquito bites and lower down on the general mosquito inhabitants. The district additionally advisable utilizing an EPA-registered insect repellent to cut back the chance of mosquito bites and to report lifeless birds at 877-968-2473.
Initially Printed: July 21, 2025 at 7:58 PM PDT