August 29, 2006

First Mosquito Pool with LaCrosse Virus Found in Nassau County

The New York State Department of Health reported today on the first isolation of LaCrosse virus from a mosquito pool in Nassau County. This is the first identification of LaCrosse virus in Nassau County for as long as records have been kept.

The mosquitoes were found in Woodbury on August 3rd. The virus was identified in a sample of Aedes vexans, a species which is active during the day as well as dusk and dawn. LaCrosse virus infection generally produces mild illness, but occasionally may progress to severe encephalitis. The disease occurs more frequently in children under the age of 16.

Nassau County has no plans to spray for adult mosquitoes at this time. The Departments of Health and Public Works have enhanced mosquito control activity in the Woodbury area. Additional samples have been taken in Woodbury and are currently being tested. The county will continue to inspect breeding sites and, when necessary, apply larvicide. Mosquito surveillance will continue at all 42 trap sites located throughout the county.

Aedes vexans is a woodland mosquito and is found in tree holes as well as artificial containers such as old tires, buckets and other containers which also may be a breeding site of the West Nile virus carrying mosquito, the Culex pipiens. The public may protect themselves from mosquitoes that may carry LaCrosse or West Nile virus by taking precautions:

• Remove or empty standing water from old tires, garbage cans, pails, or any object that can hold water.
• Make sure roof gutters drain properly, and clean clogged gutters in the spring and fall.
• Keep swimming pools chlorinated and their covers free of stagnant water
• Change the water in birdbaths every two or three days.
• Install window and door screens and keep them in good repair.
• Consider wearing long sleeves, pants, socks and mosquito repellent (according to directions) when outdoors where mosquitoes are active..

To date, no humans or horses have tested positive for West Nile in Nassau County. There have been 20 mosquito pools and one bird identified with West Nile virus.

Additional mosquito information may be obtained by calling Nassau County Department of Health at 516-571-2500 or via the County website at www.nassaucountyny.gov/health/.