The Merced County Department of Public Health reported on Monday the county's first confirmed human case of West Nile Virus. According to the public health department, the person who tested positive for WNV was hospitalized but has since been released and is expected to recover.
Stanislaus County reported its first human case of the virus on Aug. 7, and over the past two months recorded eight additional human cases of WNV.
As of Friday, there have been 12 WNV-related deaths and 245 confirmed human cases of the virus in 28 counties across California.
The Turlock Mosquito Abatement District has seen three human cases of WNV, four dead birds and 66 mosquito samples that tested positive for the virus as of Sept. 25.
“All residents, especially those over 50 years of age, and those with chronic health conditions, should take every precaution to protect themselves and their families from West Nile Virus,” said Kathleen Grassi, director of the Merced County Department of Public Health. “There are simple steps that can be taken to reduce the risk of being bitten by mosquitoes and contracting this disease.”
West Nile virus is transmitted to humans and animals through a mosquito bite. Mosquitoes become infected when they feed on infected birds.
In the United States, most people are infected from June through September, and the number of these infections usually peaks in mid-August, according to the Centers for Disease Control. Seasonal outbreaks often occur in local areas that can vary from year to year.
Approximately 1 in 5 people who are infected with West Nile virus will develop symptoms such as fever, headache, body aches, joint pains, vomiting, diarrhea, or rash. Less than 1 percent will develop a serious neurologic illness such as encephalitis or meningitis (inflammation of the brain or surrounding tissues). About 10 percent of people who develop neurologic infection due to West Nile virus will die, according to the CDC. People over 50 years of age and those with certain medical conditions, such as cancer, diabetes, hypertension, kidney disease, and organ transplants, are at greater risk for serious illness. There are no medications to treat or vaccines to prevent West Nile virus infection. People with milder illnesses typically recover on their own, although symptoms may last for several weeks or months. In the neuroinvasive forms, patients can suffer severe and sometimes long-term symptoms.
The California Department of Public Health recommends that individuals prevent exposure to mosquito bites and West Nile virus by practicing the “Three Ds:”
1. DEET – Apply insect repellent containing DEET, picaradin, oil of lemon eucalyptus or IR3535 according to label instructions. Repellents keep the mosquitoes from biting you. DEET can be used safely on infants and children 2 months of age and older.
2. DAWN AND DUSK – Mosquitoes bite in the early morning and evening so it is important to wear proper clothing and repellent if outside during these times. Make sure that your doors and windows have tight-fitting screens to keep out mosquitoes. Repair or replace screens with tears or holes.
3. DRAIN – Mosquitoes lay their eggs on standing water. Eliminate all sources of standing water on your property, including flower pots, old car tires, rain gutters and pet bowls. If you know of a swimming pool that is not being properly maintained, please contact your local mosquito and vector control agency.
Both the Eastside and Turlock Mosquito Abatement districts can treat mosquito habitats using ground and aerial spray equipment. The districts use aircraft in rural locations and ground equipment for more precision spraying in urbanized areas. The districts continue to be concerned with neglected swimming pools. The districts also provide mosquito fish, free of charge, to put in ornamental ponds and other backyard locations.
Reporting and testing of dead birds is an important step in preventing West Nile Virus. A confirmed case of the virus in dead birds or mosquito samples helps to identify areas that need treatment to reduce mosquito activity. To report a dead bird, call the California State hotline at 1-877-WNV-BIRD or report it online at www.westnile.ca.gov. Birds of particular interest are crows, ravens, magpies, jays and raptors (hawk or eagle).
To report mosquito-breeding problem areas, Stanislaus County residents should contact one of the two mosquito abatement districts that serve the county. For Stanislaus County addresses north of the Tuolumne River, residents should call the Eastside Mosquito Abatement District at 522-4098 (www.eastsidemosquito.com) and all others should contact the Turlock Mosquito Abatement District at 634-1234 (turlockmosquito.org).