Home to the highest rate of mosquito-carried West Nile virus in York County, York City will get a second dose of skeeter-killing pesticides Thursday.

About two-thirds of the city was doused in a fog of Permethrin on August 22. The Penn State Extension's West Nile detection program will be back Thursday evening to spray a "couple key areas that we continue to have problems," said Tom Smith, the program's York County administrator.

The density of urban areas like York City means those residents run the highest risk of contracting West Nile virus.

"It's a largely populated area. You have people not taking care of their properties. You have abandoned properties," Smith said.

There have not been any human cases of West Nile virus in the city this year, but the local detection program continues to find the most virus-infected mosquitoes there, Smith said. The rates are high statewide.

"Right now it is the worst it's ever been," Smith said. "Last year was our worst year on record, and we expect to double that this year."

At least one York City official has been fielding calls for weeks about the mosquito problem. Councilman Michael Helfrich said more than a dozen people have contacted him "saying they can't even go outside their houses."

Helfrich called the situation a "problem that we can help solve."

Because mosquitoes breed in standing water, even a small bucket that has stagnant water in it for four days can become home to many mosquitoes. Helfrich urged property owners to clean up garbage and stop littering.

"It's no longer about how pretty your neighborhood is," Helfrich said. "It's about your kids and your grandparents getting sick with something that can kill them."

Neighborhoods to be sprayed include the community east of Roosevelt Avenue, south of state Route 30, north of Parkway Boulevard and along Pennsylvania Avenue; the community east of Broad Street, west of East Street and Harrison Avenue and north of Philadelphia Street to the city's northern boundary; and the community south of West Market Street, west of South George Street, east of Richland Avenue and north of West Springettsbury Avenue.

Smith said he plans to conduct more tests Friday, which will determine where spraying will continue.

Spraying in York City will begin this evening. The chemical that kills the mosquitoes is safe for humans, Smith said.

However, people should stay inside when the trucks are nearby. The chemical hangs in the air like a fog, Smith said.

"It hangs there for the mosquitoes to fly through. When they come in contact with it, it kills them," he said.