New York State Health Commissioner Responds to Encephalitis Epidemic, Discovery of West Nile-Like Virus
Albany, September 27, 1999 – New York State Health Commissioner Antonia C. Novello, M.D. today announced that human cases of encephalitis caused by the West Nile–like virus have been identified in New York City and two surrounding counties and that the State will take strong measures in response to the epidemic. The virus also has been identified in birds, particularly crows.
Dr. Novello said that the U.S. Centers for Disease Control and Prevention (CDC) is reporting 37 laboratory positive cases of West Nile–like infection, including those individuals who previously had been diagnosed with St. Louis encephalitis (SLE), and other patients whose cases had not previously been considered part of the encephalitis outbreak. That number represents twice the number of people identified as infected than was previously reported. Laboratory tests will continue to try to identify other persons who had clinical symptoms of encephalitis but who were not diagnosed with SLE.
Using a molecular diagnostic technique, an independent research team led by Dr. Ian Lipkin at the University of California/Irvine has identified a viral footprint for West Nile–like or Kunjin–like virus in three encephalitis patients who have died in the outbreak. West Nile and Kunjin are genetically very similar.
"We now know that cases of West Nile–like encephalitis have occurred in New York City, Westchester County and Nassau County," Dr. Novello said. "Recently, dead or sick wild birds, especially crows, have been reported from five downstate counties and New York City. Because human illness is transmitted by mosquitos that feed on infected birds, and because the scope of the epidemic has broadened, New York State is mounting a multi–agency response to this public health emergency.
"It is important to stress that mosquito control measures that have been taken so far by York City and Westchester County are effective against West Nile–like virus as well as SLE. As we fight this new virus together, counties will continue to make individual decisions about whether and where to spray."
At the direction of Governor George E. Pataki, the State Health Department, with assistance from the State Department of Environmental Conservation (DEC), State Emergency Management Office (SEMO) and the CDC, will take the lead in assisting those counties affected by the outbreak and conducting disease surveillance to identify previously unaffected areas that may be at risk. Response measures include:
- Upon local request, the State will declare a public health emergency in counties with laboratory–positive human cases of West Nile–like virus and large amounts of dead birds reported. This will allow affected counties to initiate mosquito control measures quickly;
- Establishment of a mosquito control command center to provide guidance to counties about mosquito trapping and vector control;
- Provision of any necessary technical assistance by State agency staff, including medical entomologists, epidemiologists, laboratory experts in insect–borne viral disease, wildlife management and pesticide experts from DEC, and staff from SEMO;
- Establishment of a toll–free hotline, 1–800–962–SEMO, which will be staffed daily from 8 a.m. to 8 p.m. to answer questions from the public about West Nile–like virus, prevention measures, and what to do with dead birds; and
- Establishment of strict protocols for submission of bird specimens and for safely testing dead birds for the presence of the West Nile–like virus. Because the virus has never before been identified in the Western hemisphere, to protect wildlife pathologists who will test bird specimens, CDC has advised that necropsy procedures be conducted in accordance with rabies protocols.
To date, 523 dead birds have been reported, including 283 from Westchester County, 180 from Nassau County and others from New York City, Suffolk County, Sullivan County and Rockland County. Nearly three–quarters of the dead birds have been crows. Individuals who notice unusual bird kills should contact their county health departments or the New York State hotline (1–800–962–SEMO) to ascertain if the birds should be tested. Compliance with rabies protocols requires dead birds be handled with gloves and double–bagged in plastic.
The best way to protect against infection with the West Nile–like virus is to avoid being bitten by the mosquitoes that transmit it. The virus can cause milder symptoms such as headache and skin rash as well as encephalitis. Most cases of serious illness have occurred among elderly individuals.
Dr. Novello is advising people who live in counties which have had cases of West Nile–virus diagnosed, or in areas which have experienced unusual numbers of crow deaths to take the following precautions:
- Eliminate any items that may collect standing water that provides a mosquito–breeding area from your premises;
- Minimize outdoor activities between dusk and dawn;
- Wear long sleeve shirts and long pants if you are spending time outdoors in likely mosquito habitats such as woods or wetlands; and
- Use an insect repellant containing DEET, according to label instructions, if you will be spending time outdoors in mosquito infested areas (DEET fact sheet follows).
Deet Tips: Protecting Yourself With Deet, and Protecting Yourself From Deet
The chemical N,N–diethyl–m–toluamide –– more commonly know as DEET –– is an insect repellent that can prevent mosquito bites but must be used with caution. The New York State Department of Health recommends taking these precautions when using repellents containing DEET:
- Store bottle out of the reach of children and read all instructions on label before applying.
- Do not let children apply DEET themselves.
- Avoid prolonged and excessive use of DEET. Use sparingly to cover exposed skin; do not treat unexposed skin.
- Do not apply to eyes, nose or mouth and do not apply to hands of small children.
- Avoid use of DEET products on irritated or damaged skin.
- Do not apply repellents in enclosed areas or directly on face.
- DEET can be applied to clothing, but may damage some synthetic fabrics and plastics.
- Wash treated skin and clothing after returning indoors.
- If you believe you are having an adverse reaction to a repellent containing DEET, wash the treated area immediately.
- Remember that the use of DEET alone is not enough to eliminate risk of mosquito bites. Take other precautions –– such as wearing long pants and long sleeve shirts.