While there have been 25,000 confirmed Zika cases in the U.S., reports and confirmed cases of West Nile virus, a mosquito-borne and potentially fatal illness, continue to mount in various regions this week.

Six people in Long Island, New York, have been infected with West Nile virus, with three in Nassau County and three in Suffolk County, health officials reported on Monday.

Another recent case was reported in Burnett County, Wisconsin, which has a population of roughly 15,000. Burnett County Department of Health and Human Services reported a dead bird that tested positive for the virus, the Washburn County Register reported on Tuesday.

Jackson, Mississippi, also reported four actual cases of the virus which were confirmed by Mississippi health officials on Monday, WAPT-TV reported.

Mosquitoes in Kentucky tested positive for the West Nile virus, as well. A man from Louisville, Kentucky, aged 73, died last month after contracting the virus, the Washington Post reported.

Forty-six states and the District of Columbia have reported West Nile virus infections in people, birds, or mosquitoes in 2016, with 1,162 reported cases, according to Centers for Disease Control and Prevention.

The West Nile virus is transmitted through mosquito bites, and the bugs become infected after feeding on birds carrying the virus. The incubation period is 2-6 days but can range to 14 days, the CDC reports.

Of those infected, 70 to 80 percent do not exhibit symptoms. However, one out of five will display symptoms, all of which include body aches, joint pain, fever, vomiting, diarrhea, and rash. A full recovery is possible, although there is no known vaccine for the virus to date.

The CDC relays that the most effective method to limiting exposure to the virus is mosquito prevention.