Stanislaus County health officials confirmed a dead bird found in Modesto earlier this month tested positive for the West Nile virus, marking the presence of the debilitating disease in the region earlier than the previous year.
The Turlock Mosquito Abatement District and the Eastside Mosquito Abatement District started their efforts to control the area’s mosquito population in April as more mosquito breeding spots were discovered and reported.
“The mild winter weather in 2014 allowed mosquitoes and virus to have a head start in becoming established. With similar conditions this past winter, we are concerned 2015 could be another year with high West Nile virus activity,” said David Heft, general manager of the Turlock Mosquito Abatement District.
As of May 15, West Nile virus has been found in 18 dead birds and 17 mosquito samples in 10 California counties. To date there are no human or horse cases of West Nile reported. The virus has not been detected in Merced or San Joaquin counties at this time.
In 2014, the first dead bird to test positive for West Nile virus in Stanislaus County wasn’t announced until June. That same year marked a period that saw the second highest number of human cases of the disease in the state since it first appeared in California in 2003. In 2014, California recorded 801 cases of the potentially fatal disease.
Not only was the activity level high, but the number of serious cases and fatalities set new records, according to the CDPH. In 2014 there were a record number of deaths from West Nile virus, with 31 fatalities, and 561 cases of the West Nile neuroinvasive disease, which is the more serious neurological form of the disease often resulting in encephalitis or meningitis.
Within Stanislaus County there were two fatalities and 38 cases of the neuroinvasive form, the Stanislaus Health Services Agency reported.
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).