West Nile Virus 'At-Risk' Communities In Bucks Co. Sprayed, Put On Notice

BUCKS COUNTY, PA — Several Bucks County communities were sprayed with chemicals on Wednesday evening to control the population of mosquitoes and limit the spread of West Nile Virus.

The spraying, done via truck-mounted equipment, targeted known mosquito habitats in Hulmeville Borough, Langhorne Borough, Langhorne Manor Borough, Middletown Township, and Penndel Borough.

All residents in spray areas are at-risk of West Nile Virus and should take proper precautions, Bucks County authorities and the Pennsylvania Department of Health said.

The county uses a spray called Biomist, which uses permethrin, one of hte more common insecticides. Officials expressed confidence the spray would not harm local ecology. "These application materials have a very low toxicity profile to mammals and will have negligible impact to non-target insects and the environment," the county said in a statement.

The Biomist was dispensed at a rate of 1.5 ounces per acre.

A different type of spraying, utilizing a handheld fogging spray called Zenifex E4 RTU, dispensed the chemcial etofenprox to other communities including Bristol Township, Falls Township, and Penndel Borough. That came out at the much lower rate of 0.1 ounces per acre.

The first human positive sample of 2018 in Pennsylvania was found in Allegheny County on July 31. There have been a small handful of cases in the state over the past few years, though mosquito populations and the presence of the virus have been steadily growing.

West Nile virus appeared for the first time in Pennsylvania in birds, mosquitoes and a horse in 2000.

It is most commonly spread to humans by infected mosquitoes. It can cause febrile illness, encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord), according to the CDC.