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

New Yorkers Encouraged to Take Precautions to Prevent Mosquito Bites

Travelers Have Potential Risk of Contracting Dengue Fever or Malaria

ALBANY, N.Y. (August 7, 2024) - 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 and Eastern Equine Encephalitis.

"While we encourage New Yorkers to enjoy the outdoors, we also want them to take the proper steps to protect themselves from mosquitos and avoid potential illness," New York State Health Commissioner Dr. James McDonald said. "Infected mosquitoes can be found in outdoor areas across the state and prevention remains the most effective method of protection from exposure to mosquito transmitted diseases like West Nile Virus and Eastern Equine Encephalitis Virus."

West Nile virus (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. Since 2020, 115 human cases of WNV and 8 deaths have been reported in New York State, excluding New York City. The first human case of WNV in 2024 was reported in Suffolk County and the patient was released from the hospital last week.

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.

Eastern Equine Encephalitis (EEE) is a rarer, but extremely serious viral disease spread by mosquitoes that can affect people and horses. 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.

Travelers have a potential risk of contracting diseases like dengue fever and malaria. There is currently an increased risk of the transmission of dengue virus in the US.

Dengue fever is a disease caused by the bite of a mosquito infected with any one of four specific Dengue viruses. Dengue can cause high fever, severe headache, pain behind the eye, joint pain, and muscle pain. The mosquitos that carry this disease are mainly in tropical areas so travelers may arrive in the United States with dengue fever. Although most cases occurring in the United States are associated with travel to areas where dengue is endemic, there have been occasional outbreaks of local dengue virus transmission, particularly in southern states.

Malaria is a serious and sometimes fatal disease caused by the bite of a mosquito infected with one of four malaria blood parasites. Infected female mosquitoes are responsible for the spread of human disease. In the United States, most infections are a result of travel to foreign countries though local transmission has occurred, particularly in states such as Florida and Texas. In New York State, nearly all cases of malaria are associated with foreign travel however rare instances of local transmission of malaria have occurred in Long Island and New York City.

New Yorkers traveling to areas where dengue fever and malaria 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 West Nile Virus can be found here.

More information on Eastern Equine Encephalitis can be found here.

More information on dengue fever can be found here.

More information on malaria can be found here.