Someone in Central Maryland tested positive for West Nile virus, the first confirmed case in the state this year, the Department of Health announced Friday.

The individual, who was not publicly identified, is recovering from the mosquito-borne disease, health officials said in a statement.

Meg Sullivan, the deputy secretary for public health services, warned Marylanders to take caution against mosquito-borne diseases that are rampant during this time of the year.

“We urge people to be vigilant and take steps to avoid infection, such as eliminating standing pools of water where mosquitoes can breed,” Sullivan said in a news release.

Other tips state health officials shared include wearing insect repellent, closing windows, using screens and wearing pants and long-sleeved shirts.

What is West Nile virus?

West Nile virus is a disease spread when a human is bitten by a mosquito that got the disease from an infected bird, the Centers for Disease Control and Prevention explains. Symptoms, which can show up two to six days after being bitten, may include body aches, fever, diarrhea, headache, a rash, or vomiting.

Officials said the disease was first detected in the U.S. in 1999 in New York. Now, about 2,000 people are infected each year, the CDC says, which may be an underestimate, since some people may not show symptoms.

Maryland state health officials said the virus first appeared here in a Baltimore City crow in 1999. The first human cases didn’t appear in Maryland until 2001, officials said. The Maryland Department of Health said 18 people tested positive for West Nile virus in 2024.

This year, there have been 320 West Nile virus cases in the U.S., the latest data from the CDC shows. Last year, there were 1,791 cases in the U.S., per the CDC. Their historical data shows cases peaked nationally at 9,862 in 2003 and 5,674 in 2012.