Mosquitos collected in Silver Springs and Fernley, in Lyon County, have tested positive for the West Nile virus, the Nevada Agriculture Department said Tuesday.
The announcement follows a report Monday that a dead crow found in Carson City also tested positive, in what officials said was the first hard evidence of the virus in the state. No cases of the virus involving people have been detected yet.
State Health Officer Bradford Lee said mosquito control efforts are being increased in the communities, adding that it's important for people to take preventive measures. That includes use of insect repellent, wearing long sleeves and pants, making sure house screens fit properly and draining any standing water around homes.
State Veterinarian David Thain said people should advise health officials if they see any dead or sick birds. He also said horse owners should vaccinate horses against the virus as soon as possible.
Officials say mosquito trapping and bird surveillance will be stepped up over the next few weeks and possibly months. The monitoring is part of a statewide coordinated effort in response to the danger posed by the mosquito-borne disease.
Participants include health or mosquito control districts in Washoe, Clark, Churchill and Douglas counties, Carson City and Mason Valley. The state is coordinating activities in rural areas with no mosquito control program.
Last year, Colorado was hardest hit by the virus, with 2,947 people sickened and 61 dying, according to the federal Centers for Disease Control and Prevention.
Nationally, 9,858 people were diagnosed with health problems caused by the virus in 2003, with 262 dying.
Two Nevadans were infected with West Nile last year, but both contracted the disease while out of state, officials said.
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