The Pierce County Public Health Department announced Friday, Sept. 7, a dead crow found in Pierce County Sept. 5 has tested positive for West Nile virus. It was the first bird that tested positive for West Nile virus in Pierce County since surveillance for the mosquito-transmitted virus began May 1.
"The positive bird means that residents of Pierce County need to be more vigilant in their personal protective measures to prevent mosquito bites," Health Officer/ Public Health Director AZ Snyder said.
West Nile virus is spread to humans through the bite of an infected mosquito. Mosquitoes acquire the virus by feeding on infected birds.
"Pierce County residents should be aware of West Nile virus and take some simple steps to protect themselves against mosquito bites," Snyder said. "West Nile virus is here to stay, so the best way to avoid the disease is to reduce exposure to and eliminate breeding grounds for mosquitoes."
The Pierce County Health Public Department recommends the following:
- Limit time spent outside at dawn and dusk, when mosquitoes are most active.
- Apply an insect repellant with DEET, IR3535, picaridin, or oil of lemon eucalyptus to exposed skin and clothing.
- Make sure window and door screens are in good repair to prevent mosquito entry.
- Prevent mosquitoes from breeding by removing stagnant water from items around your property, such as tin cans, plastic containers, flower pots, discarded tires, roof gutters and downspouts.
- Turn over wheelbarrows, wading pools, boats, and canoes when not in use.
- Change the water in bird baths and pet dishes at least every three days.
- Clean and chlorinate swimming pools, outdoor saunas, and hot tubs; drain water from pool covers.
- Landscape to prevent water from pooling in low-lying areas, and trim tall grass, weeds and vines since mosquitoes use these areas to rest during hot daylight hours.
The majority of people (80 percent) who are infected with West Nile virus do not get sick. Those who do become ill usually experience mild symptoms such as fever, headache, muscle ache, rash and fatigue. Less than 1 percent of people infected with the virus get seriously ill with symptoms that include high fever, muscle weakness, stiff neck, disorientation, mental confusion, tremors, confusion, paralysis and coma.
Older adults and those with compromised immune systems are at greater risk of developing central nervous system illness that can be fatal.
The Wisconsin Department of Health Services has monitored the spread of West Nile virus since 2001 among wild birds, horses, mosquitoes and people. During 2002, the state documented its first human infections and 52 cases were reported that year. During 2017, 51 cases of West Nile virus infection were reported among Wisconsin residents.
West Nile virus infections in humans have been reported from June through October; however, most reported becoming ill with West Nile virus in August and September.
DHS will continue surveillance for West Nile virus until the end of the mosquito season. To report a sick or dead crow, blue jay or raven, please call the Dead Bird Reporting Hotline at 1-800-433-1610.
For more information on West Nile virus, vist www.dhs.wisconsin.gov/arboviral/westnilevirus.htm.