LAUGHLIN — The Southern Nevada Health District has reported a second human case of West Nile virus for 2019 in Clark County. The individual is a female under the age of 50 with the neuroinvasive form of the illness who since has been hospitalized.
The first case of West Nile in Clark County was found in a woman over the age of 50 in April in the 89005 ZIP code, near Boulder City. She has fully recovered.
There were no reports of human cases of West Nile in the county last year.
As of July 5, 1,137 mosquito traps have been set throughout Clark County with 29,541 mosquitoes submitted to the SNHD health laboratory for analysis. Since June 20, West Nile has been found in seven other ZIP codes, all within the Las Vegas Valley.
There are no reports of West Nile in the Tri-state.
Micheal Cavallaro, pest abatement manager for Bullhead City, said the area has a handful of mosquito species. However, none contain the Culex gene which is known to carry diseases like West Nile.
“The detection of Culex mosquitoes are on the lower end in the area,” he said. “So, the risk to the region is minimal. West Nile partners really in the more urban areas.”
Cavallaro added that over 90% of positive West Nile detections are in Maricopa County, where just over half of Arizona’s population lives. For 2019, there are 16 confirmed cases of the virus in Arizona.
Often, people with the disease will experience very mild clinical symptoms. Those cases are known as non-neuroinvasive.
Mild symptoms include fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph glands and skin rashes. However, West Nile can cause severe neurologic illness or death.
“One case of West Nile is too much,” said Vivek Raman, SNHD environmental health supervisor. “It’s a preventable disease.”
Humans, horses and other mammals do not pass on the virus to other biting mosquitoes. It’s commonly spread through mosquitoes feeding on infected birds.
As for avoiding the bites in general, use insect repellents or wear light, long-sleeved shirts and pants, especially during dawn and dusk hours when mosquitoes are most active, or if you are going where you know they will be present.
People also can take breeding precautions in their backyards.
“Mosquitoes only need about a capful of water to lay eggs,” Cavallaro said. “So, beyond dumping out any residual water, and make sure your trash isn’t collecting water either.”
Even discarded cups and plasticwear on the side of the road can fill with enough water to host larva, especially in the desert when they are looking for any sort of moisture they can find.
“Just be proactive, especially with rain events on the horizon,” Cavallaro said.