A Bucks County woman was diagnosed with West Nile virus on Friday, bringing the number of confirmed human cases in Pennsylvania to eight this summer, according to the state's West Nile Virus Control Program.
A Lehigh County man and a Lebanon County woman were diagnosed with the virus on Thursday and a man in Centre County was confirmed to have the disease the day before that. Two men in Delaware County were diagnosed last Monday and two women – one in Lancaster County and one in Franklin County – tested positive Aug. 3.
The mosquito-borne disease causes mild, flu-like symptoms lasting only a few days for most people. But an estimated 20 percent of infected people develop West Nile fever, which can cause head and body aches, swollen lymph glands and a skin rash.
About one in 150 people who are infected develop severe complications including encephalitis – inflammation of the brain, meningitis – inflammation of the membrane encasing the brain and spinal cord and meningoencephalitis – inflammation of all of the above. Those severe infections can cause high fever, neck stiffness, disorientation, coma, tremors, convulsions, muscle weakness and paralysis and generally require hospitalization.
Out of the eight cases in Pennsylvania, three have resulted in the less serious West Nile fever, while five have led to either encephalitis or meningitis.
Though no human cases of West Nile have been reported in Philadelphia this year, out of 470 mosquitoes tested, 99 mosquitoes out of 470 tested have come up positive – most recently on Aug. 10.