Mosquitos collected in Silver Springs and Fernley tested positive for the West Nile virus, the Nevada Department of Agriculture announced Tuesday.
The announcement comes a day after news of the virus being detected in a dead crow in Carson City.
Although health officials say it is not cause for great alarm, they caution residents to take measures to prevent mosquito bites.
"Now that we have evidence of West Nile virus in mosquitos, I cannot stress enough the importance of everyone, especially people 50 years and older, to use repellent containing DEET and wear long sleeves, pants and socks when outside," said Bradford Lee, health officer. "Also, remove any standing water from around your house and check to make sure your window screens fit properly."
Horses should be vaccinated against the disease.
"It is extremely important that horse owners have their animals vaccinated for the West Nile virus," said State Veterinarian David Thain. "California has already had 11 cases of equine death due to WNV, and it's still early in the season."
Although West Nile virus may lead to swelling of the brain or the membranes around the brain and spinal cord, that is only about a 1 percent risk.
Most victims exhibit no symptoms. About one in 150 will experience headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness or paralysis.
Officials said the public can play an important role in tracking the possible spread of the disease.
"The dead crow was reported to Carson City Health Department by an alert citizen who knew we were looking for dead birds to test," Thain said. "Dead- and sick-bird reporting is an important component to our surveillance efforts."
To report a dead bird or for public health questions, call 887-2190. For animal health questions, call 688-1182 ext. 232.
ON THE NET
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Contact Teri Vance at tvance@nevadaappeal.com or at 881-1272.