Health officials in Allegheny County urged residents in Southwestern Pennsylvania to be on the lookout after large numbers of Asian Tiger mosquitoes were found in Pittsburgh’s Lawrenceville neighborhood. Although particularly annoying if allowed to establish itself, experts said the breed does not pose a threat to the spread of West Nile virus.
“They’re a big nuisance,” said Bill Todaro, entomologist with the Allegheny County Health Department. “Wherever they show up, they change the fabric of the neighborhood – nobody goes outside anymore.
“This mosquito is a bad act.”
The Asian Tiger mosquito is an invasive pest that originated in Southeast Asia and is named for the black-and-white stripes on its legs and body. It is different from more common breeds of mosquito, often referred to as the “house mosquito,” because it aggressively bites during the daytime while most mosquitoes only bite after dusk.
Amanda Witman, spokeswoman for the state Department of Environmental Protection, said while this year’s sightings of the Asian Tiger are troubling, it has not been linked to human transmission of West Nile virus in Pennsylvania.
“The Asian Tiger mosquito is not a major factor in” Pennsylvania West Nile virus “transmission,” Witman said. “This is because the Asian Tiger mosquito typically takes its blood meal from mammals and therefore does not easily acquire WNV – which is primarily hosted by birds.”
Witman said the Asian Tiger has been implicated in disease transmission in other parts of the world.
Of the 145 mosquitoes that tested positive for the virus in Pennsylvania this year, none were Asian Tigers. Last year, four Asian Tiger mosquitoes tested positive while 4,240 insects from the culex pipiens and culex restauans species were found with the virus. There are more than 60 breeds of mosquito that live in Pennsylvania.
No specimens of the Asian Tiger mosquito have been found in Washington County this year, although it was collected in the county last year.
West Nile-infected mosquitoes have been trapped in 22 counties in the state this year, including Allegheny, Butler and Lawrence counties.
Officials recommend eliminating mosquitoes by taking a number of simple precautions to get rid of standing water on residential properties. These include getting rid of items that hold water, cleaning gutters and storm drains, changing the water in birdbaths, chlorinating swimming pools and draining water from plastic furniture covers.
Mosquitoes can breed in as little as a teaspoon of water.
According to the state’s West Nile Virus Control Program’s website, West Nile Virus was first found in the United States in 1999 and in Pennsylvania in 2000. Symptoms are similar to the flu, with severe cases resulting in inflammation of the brain, the surrounding membrane or spinal column. It is particularly dangerous for those with compromised immune systems.
Health officials recommend seeing a physician if experiencing the symptoms of West Nile virus.