PHILADELPHIA — A 73-year-old Philadelphia woman died of the West Nile virus on Friday, becoming the third person in Pennsylvania to die of the virus this year, health officials said.
The woman, whose name was not released, lived in the lower northeast section of the city and was confirmed to have the virus on Thursday, Philadelphia Health Department spokesman Jeff Moran said. He said the city has no other human cases.
The death came a day after an 84-year-old Lancaster County man died of the mosquito-borne virus. An 87-year-old man from the Pittsburgh suburb of Dormont was the first person to die of West Nile virus in Pennsylvania this year on Sept. 10.
Another eight people in Pennsylvania have been confirmed to have the virus this year, but have not died from it, according to the Pennsylvania Department of Health.
West Nile virus is spread after mosquitos feed on infected birds and then bite people, other birds and animals.
The virus can cause encephalitis, a potentially lethal inflammation of the brain. It produces flu-like symptoms and can be dangerous to young children, the elderly and people with weakened immune systems.
Last year, three Pennsylvanians contracted the virus, but there were no deaths. This year, the virus has been detected in all but eight of Pennsylvania's 67 counties, according to the state's West Nile virus Web site. It was found in 17 counties last year, state Health Department spokesman Richard McGarvey said.

