Mosquitoes testing positive for West Nile found in Las Vegas Valley

The first mosquitoes of the season to test positive for West Nile virus have been detected in the Las Vegas Valley, according to the Southern Nevada Health District.

The tiny bloodsuckers carrying the mosquito-borne virus were captured by the health district’s vector surveillance program in the 89011, 89110 and 89146 ZIP codes — in the central and east Las Vegas Valley and in Henderson.

The infected insects — known as Culex mosquitoes — are different from the Aedes aegypti mosquitoes the district found for the first time last week. Those mosquitoes, which are capable of transmitting the Zika virus, have tested negative for the disease, according to the district.

Culex mosquitoes, which contract the West Nile virus by feeding on infected birds, are common in Clark County. The county had nearly 13,000 pools of mosquitoes tested for West Nile between 2004 and June 1, 2017, according to the health district. Of those groups, 373 pools have tested positive for the virus.

There has been one case of West Nile confirmed in Clark County this year, which was reported in May.

Many people who get the virus show no symptoms or relatively mild symptoms, including fever, headache, body aches, nausea and vomiting. In some cases, though, the virus can cause severe illness and even death.

Since 2004, the health district has investigated 139 potential cases of West Nile, with 106 of those coming back as probable or confirmed cases of West Nile Fever or West Nile Neuroinvasive disease, according to the district’s website. Of those, six cases were fatal.

Contact Blake Apgar at bapgar@reviewjournal.com or 702-387-5298. Follow @blakeapgar on Twitter.