The deluge of rain the region has experienced over the winter and spring is serving as a boom to the mosquito population and has health officials concerned about a potential rise in West Nile Virus this summer.
“This year is going to be a challenging year for mosquito control in Stanislaus County,” said David Heft, general manager of the Turlock Mosquito Abatement District. “Not only do we have thousands of acres flooded along river corridors in the county but irrigation customers will be receiving a full allotment of water this year.
“Last year the irrigation allocation was 18 inches,” Heft continued. “This year it will be 48 inches. That alone would make for a bad year.”
The mosquito abatement districts have already begun mosquito surveillance and control activities in the county. Residents are urged to play their part by eliminating standing water on their property and informing their local mosquito abatement district if they are being bitten by mosquitoes.
Mosquitoes like to breed in stagnant water, preferring weedy areas that provide cover. The lagoons at dairy farms make for perfect breeding grounds, but so do flooded fields, uncared for swimming pools, urban catch basins, overwatered lawns, and pretty much anything that holds water and allows it to stagnate.
Heft said the Turlock Mosquito Abatement District has been ramping up aerial photography and inspections and has begun treatments in verified trouble areas.
Local mosquito officials are hoping that a piece of the federal emergency declaration funds allocated to Stanislaus County will go towards addressing the significant public health threat that looms due to the thousands of acres of standing water present.
“We could spend our entire budget for the year right now and we would still have a mosquito problem,” Heft said.
To date, the type of mosquitoes that can carry Zika virus have not been detected in Stanislaus County.
“There are no locally mosquito transmitted cases of Zika, Dengue or Chikungunya virus in California,” said Lloyd Douglass, manager of East Side Mosquito Abatement. “We are actively trapping for the invasive species of mosquitoes that carry these diseases. “West Nile Virus, however, is in Stanislaus County and we urge people to take precautions to prevent mosquito bites.”
The cooler temperatures right now will keep the presence of the West Nile Virus at bay, but as it warms up, health officials are concerned the area could see a dramatic rise in the number of cases. In 2016, there were 30 individuals diagnosed with West Nile virus and one related death within Stanislaus County. In California, there were 483 human cases of the disease resulting in 19 fatalities according to the California in 2016.
“We need everyone using mosquito repellant this year,” Heft said.
Mosquitoes become infected with West Nile Virus when they feed on infected birds. Infected mosquitoes can then spread West Nile Virus to humans and other animals when they bite, according to the Centers for Disease Control.
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.
A 2015 CDC report indicates that for every one diagnosed case of West Nile Virus another 150 people have the disease and are either undiagnosed or misdiagnosed.
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.
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.
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.
Residents are urged to continue to report dead birds to the WNV State Hotline: 1-877-968-2473.
Reports may also be made online at www.westnile.ca.gov. Dead bird reports are an important tool for West Nile Virus detection, even if the bird is not picked up and tested. Lack of dead bird reports decreases the ability to detect higher risk locations. There are two mosquito abatement districts to serve residents in Stanislaus County. Residents north of the Tuolumne River contact the Eastside Mosquito Abatement District at (209) 522-4098. Residents south of the Tuolumne River should contact the Turlock Mosquito Abatement District at turlockmosquito.org or (209) 634-1234.