Westmoreland mosquito workshop planned to help contain insects, disease
State officials say there is a low risk of encountering mosquito-borne West Nile virus in Westmoreland County. Local experts want to keep it that way.
Chelsea Gross, West Nile virus program technician with the Westmoreland Conservation District , will lead a free workshop Wednesday to provide residents tips on reducing the number of mosquitoes living and breeding on their property.
Eliminating standing water is key, Gross said.
"Mosquitoes breed in standing water and can fully develop to the adult stage in as little as five days," she noted. "Everyone can reduce standing water on their property by eliminating old tires, draining water from outdoor containers and aerating ornamental pools."
Gross, however, takes the opposite approach as part of her job.
She prepares water-filled traps that contain straw and milk protein to attract mosquitoes so the insects can be collected weekly and tested for West Nile virus.
"It's the type of water the females are searching for to lay their eggs in," she explained. "They want an organic water."
According to Pennsylvania's West Nile Virus Control Program for the period from June 29 through last Thursday, the risk of contracting the virus was low in Westmoreland, Beaver and Lawrence counties, moderate in Allegheny and Washington counties and remote in Fayette and Greene counties.
Of nearly 5,700 samples tested statewide, 158 were positive for West Nile, records show .
Counties with the most positive results so far this year are Cumberland (17) and Delaware (14), while Dauphin and York each have 12.
Of 83 Westmoreland mosquito samples submitted for testing in Harrisburg this season, two were positive for West Nile. Gross collected one on July 6 in Latrobe and the other on July 13 in New Kensington.
As a result, she increased Latrobe sampling sites from three to five and planned to expand on the two locations she visits in New Kensington.
"I retrapped at the location and searched for mosquitoes breeding in the area," she said.
Five mosquitoes sampled had the virus among 99 tested from Allegheny County. Two were found in Pittsburgh, and the other three in Wilkinsburg.
While the mosquito season normally lasts from April through October, most cases of West Nile virus in Pennsylvania occur in mid-summer or early fall, according to state officials with the departments of Health, Agriculture and Environmental Protection.
No West Nile virus cases in humans have been reported this year statewide, but the Centers for Disease Control cited two fatal cases here last year.
Close to 80 percent of those who contract the virus have no apparent symptoms, state Department of Health spokesman Nate Wardle said.
"About 20 percent of people will develop a fever and only about 1 percent develop the more serious illness," he said.
The milder fever typically lasts a few days with no apparent long-term ill effects, state officials note. More severe cases can involve inflammation of the brain, its surrounding membrane and the spinal cord. Symptoms can range from headache and neck stiffness to disorientation, coma, convulsions and paralysis that may last several weeks, with the potential for permanent neurological effects or death.
West Nile virus is not uncommon among mosquitoes found in Pennsylvania, but a species of Aedes mosquito associated with the Zika virus hasn't been spotted in the state for more than a decade. Gross and her counterparts, however, are monitoring a related Aedes species that has a Pennsylvania presence and the potential for carrying the disease.
According to officials, Pennsylvania since 2015 has seen 149 confirmed cases of the Zika virus in people and 76 probable cases.
"The biggest issue comes ... when people travel to an area where it is prevalent, come back and have contracted the disease," Wardle said. "It's most dangerous for women who are pregnant or are looking to become pregnant."
While most people infected with the Zika virus have no symptoms or mild ones — a fever, rash, red eyes or joint pain — it has been associated with birth defects, including an abnormally small head, and with neurological problems.
A mosquito can bite an infected human and transmit the Zika virus to another person it bites, but that method of spreading the disease has not been reported in the United States, Wardle said.
Jeff Himler is a Tribune-Review staff writer. Reach him at 724-836-6622, email@example.com or via Twitter @jhimler_news.