- What is West Nile Virus (WNV)?
- How is West Nile Virus spread?
- What are the symptoms of West Nile Virus (WNV)?
- What is a dead crow density indicator?
- How can I report a dead crow or bird?
A: West Nile Virus is an arbovirus that first appeared in the United States in 1999. It is a potentially serious illness.
A: Most often, WNV is spread by the bite of an infected mosquito. Mosquitoes become infected when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals when they bite.
A: Approximately 80% of people (about 4 out of 5) who are infected with WNV will not show any symptoms at all.
Milder symptoms occur in up to 20% of the people who become infected. The milder symptoms can include fever, headache and body aches, nausea, vomiting and sometimes swollen lymph glands or a skin rash on the chest, stomach and back.
Serious symptoms occur in about 1 in 150 people infected. The severe symptoms can include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. People over 50 years of age and those with weakened immune systems or organ transplants are most at risk for the infection.
A: A Dead Crow Density Indicator is determined by the number of dead crows per square mile. The Dead Crow Density per square mile for Winnebago County generally peaks the last week of August and then sharply declines.
A density of 2.0 dead crows (per square mile) during one week is considered a high-risk indicator for human infection. When this happens, it is especially important to take protective measures, including the use of DEET repellant, wearing light-colored, loose-fitting, long-sleeved shirts and full-length pants, and avoiding outdoor activity at peak times of mosquito activity (dusk and dawn).
Besides dead crows, additional indicators of West Nile Virus (WNV) activities include the number of positive mosquito traps and pools, and WNV positives in dogs, horses, and humans. Additional information is available upon request.
A: If you see a dead crow from June through October, call the Dead Bird Hotline at 720-4245. You will be asked to leave the Zip Code where the dead crow was found. Please dispose of the dead bird yourself. The Health Department randomly collects dead birds for testing. The information you provide will be used to help identify areas that need additional mosquito control.