West Nile Season Early and Numerous

In a normal year, there would have been fewer than 200 samples that tested positive for the virus as we head into August, when the risk of being bitten by a positive mosquito is at its highest.  In 2012, we have already collected over 1200 samples at the end of July.  According to Matt Helwig, the state wide program director from the Pennsylvania Department of Environmental Protection, “This season has begun to display an unprecedented level of infection in the Culex mosquito population.” 

According to Helwig, detections began earlier than any previous year (most likely due to the warm winter/spring) and the rate of infection in the mosquito and bird populations is on track to surpass the highest recorded year (2003).  So far, Franklin County has been spared the brunt of this year’s high and early positive counts, compared to our neighbors to the east of us, in Adams, Cumberland, York and Lancaster although, compared to the historic average here in Franklin County, we are still experiencing much higher and earlier than normal numbers.  The public can track surveillance information and viral activity by county at the website http://www.westnile.state.pa.us/ under the “Surveillance” tag.  Reduce your risk of being bitten by mosquitoes by using an approved insect repellent containing DEET, Picaridin, or Oil of Lemon Eucalyptus, especially when outside in the early evening at dusk and shortly after sundown when mosquitoes are most active.  More information about repellents can be found at the Penn State Pesticide Education site here: http://blog.pested.psu.edu/2012/06/12/have-mosquitoes-now-which-repellent-to-use/ and here:  http://blog.pested.psu.edu/2012/06/18/have-mosquitoes-now-which-repellent-to-use-part-2/  Certain mosquito species carry the West Nile virus, which can cause humans to contract West Nile encephalitis, an infection that can result in an inflammation of the brain. According to the Centers for Disease Control and Prevention, all residents in areas where virus activity has been identified are at risk of contracting West Nile encephalitis.

Mosquito samples in 41 counties in Pennsylvania have been identified with the West Nile virus so far this year. No human cases have been confirmed.

Individuals can take a number of precautionary measures around their homes to help eliminate mosquito-breeding areas, including:
• Dispose of cans, buckets, plastic containers, ceramic pots or similar containers that hold water.
• Properly dispose of discarded tires that can collect water. Shallow, stagnant, anaerobic water is where most mosquitoes breed.
• Drill holes in the bottom of outdoor recycling containers.
• Have clogged roof gutters cleaned regularly to prevent clogging.
• 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.

If a resident has stagnant pools of water on their property, they can buy BTI products at lawn and garden, outdoor supply, home improvement and other stores. This naturally occurring bacterium 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 lemon eucalyptus oil. Consult with a pediatrician or family physician for questions about the use of repellant on children, as repellant is not recommended for children under the age of two months.
For more information about West Nile virus and the state’s surveillance and control program, visit www.westnile.state.pa.us.