A Second Dead Crow Tests Positive for West Nile in Jefferson County

The Jefferson County Health Department reports a dead crow that was found in Jefferson County has tested positive for West Nile virus. A total of two birds tested positive for West Nile virus in Jefferson County since surveillance for the mosquito-transmitted virus began May 1.

“The positive birds mean that residents of Jefferson County need to be more vigilant in their personal protective measures to prevent mosquito bites,” stated Gail Scott, Jefferson County Director/Health Officer. These positive West Nile Virus results in Jefferson County also mean that the Jefferson County Health Department will no longer be collecting dead bird specimens for testing this season. As soon as any county has a positive dead bird result, West Nile Virus testing of dead birds in that particular county are discontinued for the remainder of the season.

West Nile virus is spread to humans through the bite of an infected mosquito. Mosquitoes acquire the virus by feeding on infected birds.

“Jefferson County residents should be aware of West Nile virus and take some simple steps to protect themselves against mosquito bites,” Scott said. “The West Nile virus seems to be here to stay, so the best way to avoid the disease is to reduce exposure to and eliminate breeding grounds for mosquitoes.”

The Jefferson County Health Department recommends the following:

• Limit time spent outside at dawn and dusk, when mosquitoes are most active.
• Apply insect repellant to clothing as well as exposed skin since mosquitoes may bite through clothing.
• Make sure window and door screens are in good repair to prevent mosquito entry.
• Properly dispose of items that hold water, such as tin cans, plastic containers, ceramic pots, or discarded tires.
• Clean roof gutters and downspouts for proper drainage.
• Turn over wheelbarrows, wading pools, boats, and canoes when not in use.
• Change the water in birdbaths and pet dishes at least every three days.
• Clean and chlorinate swimming pools, outdoor saunas, and hot tubs; drain water from pool covers.
• Trim tall grass, weeds, and vines since mosquitoes use these areas to rest during hot daylight hours.
• Landscape to prevent water from pooling in low-lying areas.

The majority of people (80%) 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% 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 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 2015, 9 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.

The Wisconsin Division of Public Health 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 in another county, please call the Dead Bird Reporting Hotline at 1-800-433-1610.