A case of West Nile virus has been confirmed in a second Churchill County resident and is suspected in a third, and a dog has died in Washoe County as the infection continues to take its toll in Nevada.
Nevada Health Department Spokeswoman Martha Framsted said the two confirmed cases of West Nile in Churchill County are home recovering. Blood samples from the case that health officials are treating as probable have been sent to a lab in California for confirmation.
If the test is positive, it would bring the number of known or likely human cases in the state to at least seven, with three reported in Clark County and one in Washoe County. Some 40 horses have died as well.
Framsted said most people who contract West Nile virus will show few symptoms, if any.
"The good news is that most of us who become infected do not even know we have it," she said.
The virus is transmitted by mosquitoes that have fed on sick birds.
About 20 percent of those who get the illness will exhibit flu-like symptoms consistent with West Nile fever, which include general malaise, possible headache and fever.
Fewer than 1 percent of those infected become severely ill with meningitis or encephalitis. Those most at risk for the severe form of West Nile illness are the elderly and those whose immune systems are compromised.
While the infection can affect humans, birds and horses, it is rare in dogs.
Last year, the federal Centers for Disease Control and Prevention reported fewer than 40 dogs and only one cat infected with West Nile virus nationwide.
A family pet that became suddenly ill and had to be put to sleep earlier this week was infected with the virus, officials said, making it the second case of canine infection reported in Washoe County.
It was 15 years old and had a weakened immune system.
A dachshund in Washoe Valley recently became ill with serious neurological conditions, and tests of the dogs spinal fluid confirmed West Nile infection, officials said. That dog is recovering.