/West Nile virus an ongoing risk in Southern Nevada

West Nile virus an ongoing risk in Southern Nevada

Health District reports three new cases of West Nile virus

August 1, 2019

LAS VEGAS – The Southern Nevada Health District reports three more Clark County residents have neuroinvasive illness caused by the West Nile virus. All three individuals are male, and over the age of 50. These new cases bring the year’s total to 11. Nine of the 11 cases reported to the Health District had the neuroinvasive form of the illness.

“We are clearly seeing ongoing transmission of disease in both people and mosquitoes,” said Dr. Joe Iser, Chief Health Officer of the Southern Nevada Health District. “Our message to the public is that West Nile virus is here, but it is preventable. Use FDA-registered repellent when you are outdoors and eliminate standing water around your homes to prevent mosquito bites and reduce your risk.”

To date, mosquitoes have tested positive for West Nile virus in 32 unique ZIP codes throughout Clark County. The Health District’s Mosquito Surveillance Program staff have submitted more than 35,000 mosquitoes for testing. In addition to West Nile virus, the program conducts surveillance for other mosquito-borne diseases such as St. Louis encephalitis. Mosquitoes testing positive for the St. Louis encephalitis virus have been found in 11 ZIP codes in the county.

Current ZIP codes where West Nile virus-positive mosquitoes have been found include: 89005, 89002, 89014, 89021, 89030, 89031, 89032, 89035, 89040, 89052, 89084, 89101, 89102, 89106, 89107, 89108, 89110, 89117, 89118, 89120, 89122, 89123, 89128, 89129, 89131, 89135, 89138, 89139, 89143, 89149, 89166, and 89178. The Health District emphasizes the risk of West Nile virus is not limited to these areas, and people should take steps to protect themselves from mosquito bites whenever they are outdoors. Precautions include:

  • Use Environmental Protection Agency (EPA)-registered insect repellents with one of the active ingredients below.
    • DEET
    • Picaridin (known as KBR 3023 and icaridin outside the US)
    • IR3535
    • Oil of lemon eucalyptus (OLE)
    • 2-undecanone
  • Wear pants and long-sleeved shirts when outdoors.
  • Eliminate areas of standing water, including birdbaths, “green” swimming pools, and sprinkler runoff, which support mosquito breeding.

For more information visit the Health District’s website at  www.southernnevadahealthdistrict.org/Health-Topics/west-nile-virus/. For updated surveillance information go to www.southernnevadahealthdistrict.org/programs/mosquito-surveillance/weekly-arbovirus-update/.


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.