KNOX COUNTY, Ohio — A 7-year-old in Mount Vernon was diagnosed with a rare and dangerous illness that is transmitted through a mosquito bite, according to the Knox County Health Department.
The department says the La Crosse virus comes from a bite from an infected mosquito — specifically the eastern treehole mosquito, which is commonly found in wooded areas.
It is not known where the child acquired the virus, though the family recently went camping outside of Knox County. Health department staff are set to meet with the family to assess any potential breeding sites around the home.
Anyone who lives near or spends time in wooded areas is at increased risk for the virus. The best way to prevent the infection is to prevent mosquito bites, which can be done by wearing insect repellent.
The health department says those infected with the La Crosse virus have no apparent symptoms, but the ones that do develop usually begin five to 15 days after a bite from an infected mosquito and include fever, headache, nausea, vomiting and lethargy.
Severe illness from the virus can occur among children less than 16 years old and can include: seizures, coma, paralysis and a variety of neurologic complications after recovery.
Ohio has reported more human cases of the La Crosse virus than any other state in the U.S., averaging 20 a year, according to the health department.
The Ohio Department of Health says there are currently 14 cases of La Crosse in 10 Ohio counties, including Holmes, Franklin, Ashland, Geauga, Lawrence, Wood, Portage, Wayne, Hancock and Trumbull.