By NewsDesk  @infectiousdiseasenews

Health officials in Knox County, Ohio are reporting a seven-year-old Mount Vernon child has been diagnosed with La Crosse virus, a rare and dangerous illness that is transmitted through the bite from an infected mosquito.

Aedes triseriatus
Image/CDC

It is not known where the Mount Vernon child acquired the virus; the family recently spent time camping outside of Knox County.

Anyone who lives near or spends time in wooded areas is at increased risk for La Cross virus.

La Crosse virus can only be diagnosed by a healthcare provider through a blood or cerebrospinal fluid sample collected for laboratory testing.

La Crosse encephalitis virus (LACV) is transmitted to humans by the bite of an infected mosquito. Most cases of LACV disease occur in the upper Midwestern and mid-Atlantic and southeastern states.

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It was reported first in 1963 in LaCrosse, Wisconsin and the vector is thought to be a specific type of woodland mosquito (Aedes triseriatus) called the tree-hole mosquito.

Among people who become ill, initial symptoms include fever, headache, nausea, vomiting, and tiredness. Some of those who become ill develop severe neuroinvasive disease (disease that affects the nervous system).

In rare cases, long-term disability or death can result from La Crosse encephalitis.

The most effective way to prevent infection from La Crosse virus is to prevent mosquito bites. Mosquitoes bite during the day and night. Whenever residents are in areas prone to mosquitos such as high grass, damp areas or wooded areas, they are encouraged to wear insect repellent, treating their skin, clothing and gear.

It is also important to take steps to control mosquito breeding sites. Common mosquito habitats include: tires, gutters, buckets, cans, bottles, plastic containers, pet food containers and water dishes, planters and pots, including saucers and catch trays. Bird baths should be drained and refilled every 3-4 days. Mosquitoes need just a small amount of water to lay their eggs which hatch in just a day or two.

La Crosse virus is endemic in Ohio, and Ohio has reported more human cases than any other state in the United States, averaging about 20 cases per year.