Mosquito Treatments Planned for Aug. 6 and Aug. 9 in Parts of Harrisburg, Susquehanna Twp.


Weather permitting, the Dauphin County Mosquito-Borne Disease Control Program and The Pennsylvania Department of Environmental Protection (DEP) staff will apply treatments the evenings of Aug. 6 and Aug. 9 in portions of Harrisburg city and Susquehanna Township to control adult mosquito populations. The treatments will begin at approximately 8 p.m.

A make-up spray date is Aug. 10.

Samples taken by the Dauphin County Mosquito-Borne Disease Control Program in the area have shown high adult mosquito populations that can carry the West Nile Virus.

The Aug. 6 treatments will be administered using truck-mounted equipment to spray areas in the Bellevue Neighborhood and the Harrisburg and Prospect Hill Cemeteries. Aug. 9 treatments will be conducted in Midtown Harrisburg, Uptown Harrisburg, and portions of North & South Allison Hill. Any residents that have any questions concerning the spray event should contact the Dauphin County Mosquito-Borne Disease Control Program Coordinator at 717-921-8100 by 4 p.m. on Aug. 6.

The Dauphin County Conservation Districts spray equipment dispenses Biomist 3 + 15 at a rate of 0.75 ounces per acre. The active ingredient for this product is Permethrin. The pesticide application license number for this applicator is BU6665. 

The Pennsylvania Department of Environmental Protection (DEP) spray equipment dispenses Aqua Duet at a rate of .62 ounces per acre. The active ingredients for this product are Prallethrin and Sumithrin. The pesticide application license number for this applicator is BU5976. 

According to the Centers for Disease Control and Prevention, all residents in areas where virus activity has been identified are at risk of getting West Nile encephalitis.

Certain mosquito species carry the West Nile virus, which, when transmitted to people, can cause West Nile encephalitis, an infection that can result in an inflammation of the brain.

Frequently Asked Questions about Mosquito Control

  1. Should I wash down toys and other items in the yard at the time of the application?

While you can if you wish, it is not necessary to wash the items in your yard after the application. Due to our low application rates, any exposure from contact with these surfaces would be low and pose negligible risks.

  1. Should I cover the pool before the application?

No, the residues in the pool would be low and would also be diluted by the water in the pool.

  1. Should I close the windows and turn off my air conditioner?

The ULV vapor disperses readily and little movement of the material into open windows with screens would be expected. However, individuals with upper respiratory problems, such as asthma, may react to ULV applications; closing windows and turning off air conditioners is recommended to protect these individuals.

  1. How long should I wait before I let my pet out?   

When the chemical is applied at the labeled rates there are wide margins of safety for humans, dogs, cats and other mammals. Indoor pets may be "let-out" immediately following the application. Outdoor pets may be left outdoors.

  1. How long should I wait before allowing the children to enter the yard?

The ULV vapor disperses very quickly after the application. However, individuals with respiratory problems, such as asthma, may react to ULV application. People with these health issues may want to wait an hour before resuming outdoor activities in treated areas.

To learn more about WNV and prevention, visit the CDC’s Web site at For more information about the county’s program, call the Conservation District at 717-921-8100.

County Commissioners Mike Pries, Chad Saylor, and George P. Hartwick, III urge citizens to take the following precautions to reduce the mosquito population and protect themselves:

  • Buy products with Bti (Bacillus thuringiensis israelensis) – a naturally-occurring bacteria that kills mosquito larvae but is safe for people, pets and plants – for stagnant pools of water in the lawn and garden.
  • Remove any standing water in pots, containers, pool covers, tires, wheelbarrows, wading pools, roof gutters and other containers that hold water.
  • 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.
  • Reduce outdoor exposure at dawn and dusk during peak mosquito periods, usually April through October.
  • Use insect repellents according to the manufacturer’s instructions. An effective repellent will contain DEET, picaridin or oil of lemon eucalyptus. Consult with a pediatrician or family physician if you have questions about the use of repellent on children, as repellent is not recommended for children under the age of two months.