/Public Health Update West Nile Virus

Public Health Update West Nile Virus

September 21, 2011

LAS VEGAS – The Southern Nevada Health District is reporting seven new cases of West Nile virus in Clark County residents, bringing the season total to eight. The new patients include three males and four females, ages 39, 57, 73, 74, 79, 81 and 83. The seven new cases were all diagnosed with the more serious, neuroinvasive form of the illness and all are expected to recover. The first reported case was in an 84 year old man who also had the more serious form of the disease. There have been no reported deaths.

The health district vector control program has also detected West Nile virus in clusters of mosquitoes in the 89001 (Lincoln County), 89102, 89107, and 89117 zip codes. Previously, the health district reported two clusters in the Logandale area tested positive for West Nile virus. The identification of positive mosquitoes is an indication that mosquitoes carrying the virus are likely present throughout the Las Vegas Valley and serves as an important reminder to the public that West Nile virus can be prevented by using insect repellants and eliminating sources of standing water which support mosquito breeding.

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. Many people with the virus will have no symptoms or very mild clinical symptoms of illness. Mild symptoms include fever, headache, body aches, nausea, vomiting and sometimes swollen lymph glands or a skin rash on the chest stomach, and back. In some cases the virus can cause severe illness and even death. In 2010, no human cases of West Nile virus were reported in Clark County.

The health district’s environmental health specialists routinely survey and treat known breeding sources for mosquitoes and trap them for identification. In addition to West Nile virus, mosquitoes are also tested for Western equine encephalitis and St. Louis encephalitis.

The health district is no longer treating breeding sources on private properties, such as green pools. Residents can now report green swimming pools and standing or stagnant water sources to local code enforcement agencies. Contact information for local jurisdictions’ code enforcement is available on the health district website at: www.southernnevadahealthdistrict.org/forms/mosquito.php.

The health district recommends the following to prevent mosquito bites and to eliminate breeding sources:

  • 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.

For more information about West Nile virus, visit the health district website at www.SouthernNevadaHealthDistrict.org.

Updated information about the Southern Nevada Health District can be found on Facebook www.facebook.com/SouthernNevadaHealthDistrict, on YouTube www.youtube.com/SNHealthDistrict or Twitter www.twitter.com/SNHDinfo.

Visit the Media Contacts webpage for media related inquiries.


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.