/Southern Nevada Health District Reports Season First West Nile Case

Southern Nevada Health District reports season’s first West Nile Case

Prevention is urged

July 13, 2007

Las Vegas – The Southern Nevada Health District today reported Clark County’s first human West Nile virus case for 2007. The individual, a male under age 50, contracted a mild form of the illness.

To date, the health district has not reported any positive mosquitoes among any of the samples collected this year in Clark County; however, environmental health specialists are conducting surveillance and trapping activities in the area where the individual resides. The state agriculture division has reported that it located one positive bird and a positive mosquito pool, both in Northern Nevada.

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.

“As the summer progresses, it is important to practice preventive measures to avoid mosquito bites,” said Dr. Lawrence Sands, chief health officer. “Mosquitoes that can carry West Nile virus are active throughout Clark County and in neighboring counties and states,” said Sands.

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, un-maintained swimming pools and sprinkler runoff, which support mosquito breeding.

The health district’s mosquito surveillance program generally begins in spring and continues through the end of September. Environmental health specialists routinely survey and treat known breeding sources for mosquitoes and trap them for identification and testing for West Nile virus, Western equine encephalitis and St. Louis encephalitis.

In 2006, Nevada had a total of 123 human cases of West Nile virus, including one death. Three Clark County residents contracted the illness last year, all of whom contracted it while traveling outside of the area. For more information or to report mosquitoes, “green” swimming pools or stagnant water sources, visit the health district website at www.SouthernNevadaHealthDistrict.org or call the mosquito control hotline, (702) 759-1220.

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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.