More Pittsburgh Mosquitos Test Positive For West Nile Virus

Sep 1, 2015

Several Pittsburgh neighborhoods tested positive for mosquitos carrying the West Nile virus. Crews will spray affected areas late Tuesday, Sept. 1, 2015.
Credit Tom / Flickr

  Mosquitos with West Nile virus are turning up in more city neighborhoods and communities, and that means more spraying.

The Allegheny County Health Department opted to fight West Nile in Bloomfield, Polish Hill, Lawrenceville and Stanton Heights with a truck-mounted, Ultra Low Volume sprayer between 8 and 10 p.m. Tuesday after recent mosquito samples tested positive for the virus. 

“We spray the product Zenivex in those neighborhoods where we get multiple positive samples testing positive for West Nile virus,” said Dave Namey, program manager for the department's housing and community environment program. “The other thing we do, we throw a pesticide in catch basins that hold water, and this pesticide will prevent the mosquitos from becoming an adult.”

Department officials sprayed earlier this summer in Homestead, Wilkinsburg, Morningside, Highland Park and the West End. There have been no reported cases of human transmission in Allegheny County. Statewide, officials cited nine cases, all non-fatal.

“The numbers we’re seeing this year replicate 2012,” Namey said. “That’s the last year we’ve had to spray this often.”

Namey cites the weather in the area during the last few months as a possible contributor to the increase.

“I just think that this year, particularly in the summer, it was wet, wetter than usual, and then we had hot weather that also facilitates breeding,” he said.

Zenivex is not harmful to people or pets and is said to kill the majority of adult mosquitos. Only 1.5 – 3 ounces is sprayed per acre, he said.

“It’s a very low dose" Namey said. "We have not had any reports of issues of people or pets being affected by the pesticide and we don’t expect to get any.”

Namey said people can take additional measures to protect themselves from mosquito bites by removing stagnant water they may have on their property, as well as limiting their time outside. These guidelines, in addition to the ACHD pesticide treatment, lessen the risk of transmission, he said.