State Health Commissioner Urges Mosquito Precautions

Rainfall amounts, confirmation of additional mosquito-borne viruses are of concern

ALBANY, NY, July 30, 2004 — The recent weather pattern, coupled with confirmation of Eastern Equine Encephalitis (EEE) virus in mosquitoes collected from central New York, should prompt New Yorkers to take additional precautions to avoid mosquito bites, State Health Commissioner Antonia C. Novello, M.D., M.P.H. Dr.P.H., said today.

"Although the disease is rare in humans, when someone does get infected, EEE is a life-threatening illness," Dr. Novello said. "While most of the 70 species of mosquitoes in New York do not transmit disease, mosquito counts are likely to increase because of all the rain that fell during July. It's more important than ever to protect yourself from bites."

EEE virus was isolated from Culiseta melanura mosquitoes collected on July 20 from the Cicero swamp near Syracuse. The State Health Department's Wadsworth Center laboratories received the specimens for testing on July 23 and confirmed the findings yesterday. Although it is not unusual to find EEE in Cicero swamp, the virus usually does not surface this early in the summer. Historically, EEE has been isolated in late August in New York State. Earlier this month, another mosquito-borne virus, California encephalitis, was confirmed in mosquitoes from several counties, and West Nile virus continues to be present throughout the state.

"While low, the risk of serious illness from mosquito-borne diseases is real," Dr. Novello said. "Although many mosquitoes are most active at dawn and dusk and when the air is calm, others will feed any time of day. Protect yourself by using a repellent containing DEET whenever you spend time outdoors, and wear long pants and long sleeves to limit the amount of exposed skin."

DEET (N, N-diethyl-m-toluamide), is a chemical that has been proven effective against mosquitoes; however, insect repellents should always be used according to label instructions. Choose a DEET product based on your particular circumstances. For instance, you would likely need to use a lower amount and lower concentration of DEET if you were spending a short time outdoors in an area of low mosquito activity than if you were hiking in the deep woods. Do not apply DEET near the eyes, nose or mouth and use sparingly around ears. Do not apply to the hands of small children. After returning indoors, wash treated skin with soap and water.

Insect repellents containing botanical oils, such as oil of geranium, cedar, lemongrass, soy or citronella are also available, but there is limited information on their effectiveness and toxicity.

To reduce the number of mosquitoes around your property, eliminate standing water in your yard, make sure all windows and doors have screens, and that all screens are in good repair. In addition:

  • Dispose of tin cans, plastic containers, ceramic pots or similar containers in which water collects.
  • Get rid of used tires—call your local landfill or Department of Public Works to find out how to dispose of them properly.
  • Drill holes in the bottoms of recycling containers that are kept outdoors. Make sure roof gutters drain properly, and clean clogged gutters in the spring and fall.
  • Turn over plastic wading pools and wheelbarrows when not in use. Change the water in bird baths twice a week.
  • Clean vegetation and debris from the edges of ponds. Clean and chlorinate swimming pools, outdoor saunas and hot tubs.
  • Drain water from pool covers.
  • Use landscaping to eliminate stagnant water that collects on your property.

These precautions are especially important to help reduce the transmission of West Nile virus, which is spread by mosquitoes that breed in standing water. During 2003, 71 New Yorkers were infected with West Nile virus, and 10 died. So far this year, one human case of West Nile virus has been confirmed in New York.

The last human case of EEE in the state occurred in 1983. Cases in horses are more common. An outbreak of EEE in horses occurred in Onondaga County during 1990, when EEE also was isolated in mosquitoes collected from Cicero swamp during the month of July. During 2003 there were seven equine cases in New York State. In past years, along with locations in central New York (Onondaga, Oneida, Oswego and Madison counties), EEE has been found in Suffolk County and the lower Hudson Valley. Dutchess, Orange, Putnam and Ulster counties had their first isolations of EEE last year.