Residents advised to be vigilant during mosquito season

August 21, 2019

Mosquitoes carrying equine encephalitis (EEE) have been found in Department of Health and Human Services test samples from Portsmouth and Fremont in Rockingham County. Residents are urged to take precautions to reduce their exposure.

New Hampshire has recorded no human cases of EEE since 2014. The Kingston man tested positive for Jamestown Canyon virus and Powassan virus, which are carried by mosquitoes and ticks. According to State Epidemiologist Dr. Benjamin Chan, “All the mosquito-borne pathogens, EEE, Jamestown Canyon and West Nile virus present similar flu-like symptoms with fever, chills and general weakness. They can all lead to nervous system infections.”

This is the usual time of year for the diseases mosquitoes carry to spread environmentally. Dragon Mosquito of Brentwood, is contracted by the City of Portsmouth and other local communities to provide a mosquito control program that includes spraying to reduce mosquito populations. Sarah MacGregor, president of Dragon Mosquito has commented that the summer transition to fall offers the highest risk of contracting vector-borne diseases because the pathogens build up in insects and birds during the summer and then spill-over to the human population in the late summer. The risk decreases only when the mosquito population declines due to killing frost.

The most effective prevention of illness is personal protection. Dr. Chan recommends taking the following steps to protect yourself from mosquito bites: 

  • stay indoors during dawn and dusk peak times for mosquitoes
  • use insect repellent according to the manufacturers’ instructions;  
  • wear long-sleeved shirts and pants;
  • treat your clothing and gear; and
  • take steps to control mosquitoes indoors and outdoors by maintaining screens and eliminating standing water to avoid unnecessary breeding of mosquitoes on your property.

Consider the use of an effective insect repellent. Please see the CDC link below for further instructions on repellents, particularly regarding repellent use on children.

For further information on personal protection and protecting your property, please visit:

You can also follow Dragon Mosquito Control, Inc. on Facebook to keep up with the latest mosquito news.

Dragon Mosquito maintains a No-Spray Registry for residents who do not want their property treated and also provides a no-cost service to survey wetlands on private property for mosquito activity.


Mosquito bite.