What Are West Nile Symptoms? Virus Found in 30 States

While summertime brings sunny, warm days and more time outside, it also means an increased risk of bug bites—especially mosquito bites. Most mosquito bites are harmless, and the worst thing about them is the incessant itchy feeling that accompanies the bite, but some are dangerous.

Mosquitoes can carry harmful illness with them, like the West Nile virus. Just a few weeks into the official summer season and mosquitos, people and animals across 30 states have tested positive for West Nile Virus.

While the virus is active in 30 states, it had only been reported in humans in Alabama, California, New York, North and South Dakota and Oklahoma as of Tuesday, according to the Centers for Disease Control. In the other 24 states, the virus has only been found in mosquitos, birds or other animals.

cdc west nile map People and animals across 30 states have tested positive for West Nile Virus as of July 10. Centers for Disease Control

There have been 14 human cases reported so far and of those, half were neuroinvasive, meaning the virus was severe and infected the nervous system. This is also called West Nile encephalitis or meningitis. Only about one in every 150 people who contract West Nile will end up with a case this severe.

What Is West Nile Virus?

The West Nile virus originated in Uganda in 1937 when it was isolated in a woman in the West Nile area of the country, according to the World Health Organization. It’s been reported in other countries for more than 50 years. Most people who end up with West Nile get it from a mosquito bite. Mosquitos can contract the virus after feeding on an infected bird, and then pass the virus on to any human it bites.

What Are the Symptoms of West Nile?

Most people who get West Nile don’t exhibit symptoms of the virus. Only one in five people will actually develop symptoms. The incubation period for the virus is anywhere from three days to two weeks. Those who do actually have symptoms usually experience a fever along with a headache, body and joint aches and pain, vomiting, diarrhea and sometimes a rash, according to the CDC.

In more severe cases, those infected can experience those symptoms in addition to coma, convulsions, vision loss, numbness, paralysis and more. This severe illness is more common in those over 60 years of age and those with compromised immune systems.

It can take weeks or months for a person to recover from a West Nile virus infection, according to the CDC.

mosquito A female Aedes aegypti mosquito is shown in this 2006 Center for Disease Control (CDC) photograph. Mosquitoes can carry harmful illness with them, like the West Nile virus. James Gathany/Reuters

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