Beaver and Dauphin counties have also had mosquitoes turn up infected.
It is not exactly an epidemic yet, though. According to the program’s website, more than 5,000 samples in 50 of Pennsylvania’s 67 counties have been collected from mosquito pools and birds, with 531 actually tested. Just four mosquito samples have shown infection. No human cases have been reported to date in 2014.
The state Department of Health would like to see it stay that way.
“This is certainly a time when we want to remind people to wear bug spray, to keep as much of your skin covered as you can, especially in the early evening hours,” spokeswoman Holli Senior said.
Centre County will be spraying for mosquitoes in the Rush Township area Wednesday evening to control the adult insect population. In the event of rain, spraying would move to Thursday.
Bert Lavan, Centre County’s West Nile coordinator, said the Moshannon Valley activity is “nuisance spraying,” done annually because of the wetland environments around Philipsburg and Rush Township, which create a unique breeding ground for the bugs.
His department sets traps to determine how many mosquitoes are in the area. If the population reaches a certain threshold, spraying is done.
Prompted by the numbers yielded by traps, the Moshannon Valley area is usually sprayed three times a year.
However, the virus-infected mosquito sample this year didn’t come from that area. It was collected in Spring Township.
Lavan said additional spraying in other areas could be done if infection numbers suggest it is necessary.
West Nile virus is transmitted by mosquitoes, who pick it up from feeding on infected birds. In humans, it can cause fever, headaches swollen glands and, in rare cases, encephalitis, an inflammation of the brain that can include tremors, coma and paralysis.
In Pennsylvania, 28 people have died of West Nile virus since 2000, according to the state Department of Environmental Protection.
DEP encourages residents to keep the mosquito population down by eliminating standing water from properties wherever possible to cut down on breeding areas, and by trimming grass and bushes to reduce resting areas for adult insects.