The Department of Environmental Protection said it has found mosquitoes infected with the virus in 51 of Pennsylvania's 67 counties. The best method to reduce the risk of infections is avoiding mosquito bites. The increase, officials said, is widespread across the county and has happened earlier this summer, compared with previous years. According to World Health Organisation, there is one reported case of transplacental (mother-to-child) WNV transmission.
The number of confirmed infections can vary from year to year.
The state is checking the case of an Allegheny County resident, sending samples to the Centers for Disease Control and Prevention. In Virginia, there were 13, and in the District, there were four. Tests results confirmed West Nile Virus Thursday.More news: Google sets down ground rules for notch support on Android P
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Symptoms of West Nile Virus include fever, headache, body aches, nausea, vomiting, swollen lymph glands, a rash on the chest, stomach or back, and a fever. Less than one percent of infected people develop the neuro-invasive form of the illness. The most vulnerable people are those who are at least 50 or have weakened immune systems. Anyone who thinks they may be infected should see a doctor immediately, officials said.
"With high levels of [West Nile Virus] in mosquitoes and the recent rains leading to even more mosquitoes, it's important for residents of Fairfax County to take precautions to protect themselves and their families", the Fairfax County Health Department said in a news release. The types of mosquitoes that transmit WNV to humans most commonly breed in urban areas in places that hold water such as bird baths, plant pots, old toys and tires.