These findings are the first detection of WNV in Stanislaus County this year. As of June 20, 21 California counties have detected WNV. One person experienced an asymptomatic infection from San Joaquin County, and one human case was reported from Contra Costa county.
Dr. Ron Chapman, Director of the California Department of Public Health (CDPH) and state health officer, confirmed these first two human infections. The patient from Contra Costa County has since recovered and been released from the hospital; the patient from San Joaquin County has tested positive for the virus but is not showing symptoms at this time. A total of 196 dead birds, 123 mosquito samples, and one sentinel chicken flock have been reported with WNV in those counties.
According to the Centers for Disease Control and Prevention, 70 to 80 percent of people who become infected with West Nile virus do not develop any symptoms. Febrile illness from WNV only occurs in some people. About 20 percent of people who are infected will develop a fever with other symptoms such as headache, body aches, joint pains, vomiting, diarrhea, or rash. Most people with this type of West Nile virus disease recover completely, but fatigue and weakness can last as long as weeks or months.
The StanEmergency website also lists that according to the CDC, West Nile virus is spread by the bite of an infected mosquito, and aside from people and birds, can affect horses and some other animals.
Only on rare occasions can an infection result in a severe and sometimes fatal illness known as West Nile encephalitis, which is an inflammation of the brain. The CDC also states that risk of severe disease is higher for persons 50 years of age and older.
To prevent the spread of WNV, the Turlock and East Side Mosquito Abatement Districts want citizens to take simple steps to help protect themselves and others from mosquito bites and WNV:
- Eliminate sources of standing water. During warm weather, mosquitoes can breed within four days. Be sure to change water in pet dishes and bird baths regularly, and drill holes in tire swings so water can drain.
- Avoid spending time outside during dusk and dawn, especially for the first two hours after sunset, when mosquitoes are most active.
- When outdoors, wear long pants, long-sleeved shirts, and other protective clothing.
- Keep mosquitoes out of your home with tight-fitting screens on doors and windows.
- Apply insect repellent with the active ingredient DEET when outdoors.
- In addition to DEET-based products, the CDC also recommends repellents containing oil of lemon eucalyptus and Picaridin.
Officials say reporting and testing of dead birds is important to preventing WNV. Confirmed cases of WNV in birds or mosquitoes help to identify areas that need to be treated for mosquitoes and WNV.
To report a dead bird, call the California state hotline at 1-877-WNV-BIRD or report it online at www.westnile.ca.gov.