City of Portsmouth Logo

July 29, 2009

Contact: Harry Bennett - (757) 393-8585, ext. 8528


Mosquito Pool Tests Positive for Eastern Equine Encephalitis (EEE)

Portsmouth, VA -- Dr. Demetria Lindsay, M.D., Director of the Portsmouth Health Department, announced today that a mosquito pool has tested positive for Eastern Equine Encephalitis (EEE). This is the first indication of EEE virus activity in Portsmouth in 2009. This is typically the time of year that positive mosquito pools are found in Portsmouth. The mosquito pool was collected off Mayflower Road in the Mayflower Park area of the city on July 21. The EEE positive mosquito pool identified, Culiseta melanura, feeds only on birds and serves as an early warning indicator of EEE activity in the local bird population.

History has shown mosquitoes test positive first for the virus. Several weeks later, animals may become infected including birds and horses. These animals are exposed to mosquitoes much more than humans. Within several more weeks, human cases of EEE could potentially develop.

Although human cases of EEE are not common, the more mosquito bites one gets, the higher the risk of exposure to mosquito borne diseases. Therefore, people in Portsmouth should take extra precautions to avoid being bitten by mosquitoes this summer. Most people bitten by an infected mosquito do not get sick. People who do get sick usually suffer a mild flu-like illness. Those over age 50 are at greatest risk of serious illness, such as encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord).

There is a vaccine to protect horses, but not for humans. The Portsmouth Health Department recommends the following tips to reduce exposure to mosquitoes:

  • Wear long, loose and light-colored clothing.
  • Make sure window and door screens in your home are functional and in place.
  • Use insect repellent products registered with the Environmental Protection Agency such as products containing DEET, Picaridin, or Oil of Lemon Eucalyptus. When using a product containing DEET, no more than 50 percent DEET should be used for adults and less than 30 percent should be used for children. Follow instructions when using insect repellents.
  • Turn over, drain, or remove containers in your yard where water collects, such as old tires, potted plant trays, buckets and toys.
  • Fill in or drain root-ball holes (from downed trees) or any depression that holds water for more than a week.
  • Eliminate standing water on tarps or flat roofs, and in boats.
  • Clean out birdbaths and wading pools once a week.
  • Clean roof gutters and downspout screens regularly.

For additional information, please visit the Virginia Department of Health’s website at

# # #