/West Nile Virus

West Nile Virus

September 4, 2009

The Southern Nevada Health District reports a total of 12 human cases associated with West Nile virus in Clark County residents. In addition, the health district’s vector control program has detected West Nile virus in mosquito clusters in the 89129 and 89142 zip codes. Updates are posted to the health district website Friday by noon.

The health district’ s vector control program previously detected West Nile virus in mosquito clusters in the 89011, 89014, 89103, 89107, 89119 and 89122 zip codes. It is important to note that although West Nile positive mosquitoes have been identified in these Southern Nevada zip codes, residents throughout the area are urged to take precautions to prevent mosquito breeding and to prevent mosquito bites. West Nile is present throughout the Valley and any one location is not at a higher or lower risk than another.

On July 1, the health district reported Clark County’s first human case associated with West Nile virus for 2009. In 2008, Nevada reported 16 human cases of West Nile virus.

The health district’s environmental health specialists routinely survey and treat known breeding sources for mosquitoes and trap them for identification. In addition, they are tested for West Nile virus, Western equine encephalitis and St. Louis encephalitis. West Nile virus is spread through the bite of infected mosquitoes, which acquire the virus by feeding on infected birds. The illness is not spread person to person.

The health district strongly stresses the need for individual protective actions to avoid mosquito bites:

  • Apply an insect repellent containing DEET (N, N-diethyl-meta-toluamide) according to manufacturer’s directions. Repellents containing picaridin and oil of lemon eucalyptus also have some efficacy. However, DEET is the best-studied and most-effective repellant available.
  • Wear pants and long-sleeved shirts, when outdoors.
  • Avoid spending time outside when mosquitoes are most active, notably at dusk (the first two hours after sunset) and dawn.
  • Eliminate areas of standing water, including bird baths, “green” swimming pools and sprinkler runoff, which support mosquito breeding.

Further updates will be posted to the Southern Nevada Health District website, www.SouthernNevadaHealthDistrict.org.

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The Southern Nevada Health District serves as the local public health authority for Clark County, Boulder City, Henderson, Las Vegas, Mesquite and North Las Vegas. The agency safeguards the public health of the community’s residents and visitors through innovative programs, regulations, and initiatives focused on protecting and promoting their health and well-being. More information about the Health District, its programs, services, and the regulatory oversight it provides is available at www.SNHD.info.