Starting in the wee hours of Wednesday, the Penn State Extension for Lehigh County will send a truck to spray some of the prime breeding grounds for mosquitoes in Bethlehem to combat West Nile Virus.
To date, 37 mosquitoes and birds have tested positive for West Nile Virus in Lehigh County. Six mosquitoes have tested positive in the city, two more in Bethlehem Township and one mosquito in Fountain Hill also tested positive.
The spray – Methoprene SR20 – is safe for people and other mammals, according to Matt Helwig of the state Department of Environmental Protection’s West Nile Virus Program. Helwig said the spray affects the growth cycle of larval mosquitoes so they don’t become adults that can transmit West Nile.
"It’s very safe,” he said of Methoprene SR20. “It actually has no non-target impacts. It mimics mosquito hormones.”
The spraying will be the second in the Lehigh Valley this summer – the first was in parts of Allentown July 26 -- but could be followed at some point by spraying aimed at adult mosquitoes, according to Louise Bugbee, West Nile coordinator for Lehigh County.
The application on Wednesday will begin about 3:30 a.m. on the west side of Bethlehem and some of Center City, she said.
The application on July 26 in Allentown was largely along Sumner Avenue and Front Street in the First and Sixth Wards of the city, Bugbee said. The area has some scrap metal and recycling facilities that can be conducive for mosquito breeding.
Northampton County dissolved its Vector Control program a few years ago and now efforts at West Nile Virus control are done by a DEP biologist who covers several counties in the Northeast region, she said.
As of Monday, Lehigh County had 37 mosquitoes or birds that tested positive for West Nile and Northampton County had 15, according to the state. In Lehigh County, positive West Nile Virus tests have been found in mosquitoes or birds in the municipalities of Salisbury, South Whitehall, North Whitehall, Bethlehem, Upper Macungie, Upper Saucon, Lower Macungie and Fountain Hill, among others.
In Northampton County, positive tests of mosquitoes or birds have been found in Bethlehem Township, the city of Bethlehem, Easton, Wind Gap and Hanover Township.
West Nile Virus can cause encephalitis -- inflammation of the brain. Mosquitoes can pass on the disease to birds and other animals, as well as people. A mild case of West Nile might manifest itself with flu-like symptoms with a fever lasting a few days. The most serious cases cause West Nile encephalitis, West Nile meningitis or West Nile meningoencephalitis.
Bugbee urged residents to take part in the effort to combat the disease by getting rid of even small puddles of standing water outside. “Remind people to clean up their junk,” she said. Mosquitoes can lay and hatch eggs in a day or two during warm weather so getting rid of stagnant water is key.
DEP offers this list of measures people can take around the home to help eliminate mosquito-breeding areas:
• Dispose of cans, buckets, plastic containers, ceramic pots or similar containers that hold water on your property.
• Properly dispose of discarded tires that can collect water. Stagnant water is where most mosquitoes breed.
• Drill holes in the bottom of outdoor recycling containers.
• Clean clogged roof gutters every year, particularly if the leaves from surrounding trees tend to plug drains.
• Turn over plastic wading pools when not in use.
• Turn over wheelbarrows and don’t let water stagnate in birdbaths.
• Aerate ornamental pools or stock them with fish.
• Clean and chlorinate swimming pools not in use and remove any water that may collect on pool covers.
For stagnant pools of water, homeowners can buy Bti products at lawn and garden, outdoor supply, home improvement and other stores. This naturally occurring bacteria kills mosquito larva, but is safe for people, pets, aquatic life and plants.
Additionally, these simple precautions can prevent mosquito bites, particularly for people who are most at risk:
• Make sure screens fit tightly over doors and windows to keep mosquitoes out of homes.
• Consider wearing long-sleeved shirts, long pants and socks when outdoors, particularly when mosquitoes are most active at dawn and dusk, or in areas known for having large numbers of mosquitoes.
• When possible, reduce outdoor exposure at dawn and dusk during peak mosquito periods, usually April through October.
• Use insect repellants according to the manufacturer’s instructions. An effective repellant will contain DEET, picaridin or oil of lemon eucalyptus. Consult with a pediatrician or family physician if you have questions about the use of repellant on children, as repellant is not recommended for children under the age of 2 months.