New York State Department of Health Reminds New Yorkers to Take Precautions Against West Nile Virus and Eastern Equine Encephalitis

First West Nile Case Reported This Year in New York State

First Eastern Equine Encephalitis Virus Findings in Mosquitoes Reported in New York State

New Yorkers Encouraged to Take Precautions to Prevent Mosquito Bites

Travelers Have Potential Risk of Contracting Mosquito-borne Illnesses While Abroad

ALBANY, N.Y. (July 22, 2025) - The New York State Department of Health reminds New Yorkers that with the arrival of warmer temperatures, it is important to take precautions to prevent mosquito bites and protect against diseases like West Nile Virus (WNV) and Eastern Equine Encephalitis (EEE).

"While we encourage New Yorkers to enjoy the outdoors, we also want them to take sensible precautions against mosquitos and avoid potential serious illness, such as West Nile Virus and Eastern Equine Encephalitis" New York State Health Commissioner Dr. James McDonald said. "Infected mosquitoes look just like regular mosquitoes and can be found in outdoor areas across the state. You can prevent mosquito bites by utilizing insect repellent, avoiding standing water near your home and using screens in open windows."

WNV, an infection that can cause serious illness and, in some cases, death, is transmitted to humans and some animals through the bite of an infected mosquito. Not all mosquitoes carry WNV, which was first identified in New York State in 1999. In 2024 alone there were 100 cases of WNV reported in New York State, the highest number of cases reported in a single year in over a decade. The first human case of WNV in 2025 was reported in Onondaga County; the patient was hospitalized, has since been discharged, and is currently recovering.

Most people infected with WNV do not develop any signs or symptoms. If illness develops, symptoms usually occur 3-15 days after the bite from an infected mosquito. People with mild cases of WNV may develop fever, headache, body aches and occasionally a skin rash or swollen glands. People with severe WNV may have a sudden onset of headache, high fever, neck stiffness, muscle weakness, altered mental status, tremors, convulsions, and/or paralysis and in some cases, severe WNV can result in death.

EEE is a rarer, but extremely serious viral disease spread by mosquitoes that can affect people and horses. There was an unprecedented level of EEE activity in New York State last year with two human cases including one death, 22 equine cases, and two avian cases across 18 counties. To date in 2025, EEE has been detected in mosquitoes in Onondaga County. People of all ages are susceptible to infection, but people over 50 and younger than 15 are at greatest risk of acquiring the virus. While most people bitten by an infected mosquito will not develop any symptoms, severe cases may begin with the sudden onset of headache, high fever, chills, and vomiting. The illness may then progress into disorientation, seizures, encephalitis, and coma. Approximately a third of patients who develop EEE die, while many patients who survive EEE experience neurologic impairment.

There is no commercially available human vaccine for EEE or WNV, and the best protection is to prevent mosquito bites.

The following precautions are highly recommended to reduce risk of infection from WNV and EEE:

  • Consider wearing long sleeves and tucking pants into socks and shirts into pants when outdoors at dusk or dawn, the time of day when mosquitoes are most active.
  • Use insect repellents containing DEET. More information on repellents can be found here. Be sure to follow the insect repellent label directions. Children should not handle repellents directly. Instead, adults should apply repellents to their own hands first and then gently spread on the child's exposed skin. Avoid applying directly to children's hands. After returning indoors, wash your child's treated skin and clothing with soap and water or give the child a bath.
  • Make sure there are screens in windows and doors of the home. Make sure the screens are free of rips, tears, and holes.
  • Eliminate all standing water in yards and around the home and property where mosquitoes can breed, including plastic containers, pool covers, wading pools, ceramic pots, clogged drainpipes, and wheelbarrows. Also change water in bird baths twice a week.

New Yorkers also have a potential risk of contracting mosquito-borne diseases when traveling abroad. Diseases such as dengue, malaria, chikungunya, Oropouche, yellow fever, and malaria are circulating in other parts of the world. Travelers are reminded to visit the CDC Travel Notice page prior to travel to learn about disease outbreaks in destinations around the world. Currently, CDC has issued travel alerts for chikungunya in Bolivia and the Indian Ocean region, Oropouche in the Americas, yellow fever in South America, malaria in Ethiopia, as well as a global dengue alert.

New Yorkers traveling to areas where mosquito-borne diseases are present and those returning from areas where these diseases are present should protect themselves from mosquito bites using the same prevention measures recommended to protect against WNV and EEE.

More information on mosquito-borne diseases can be found here.