AUGUSTA, Maine — The Maine Center for Disease Control and Prevention has confirmed the presence of Eastern equine encephalitis, or EEE, in mosquito pools in the towns of Alfred and York in York County.
Friday’s announcement marked the third time in less than a month that mosquito pools in southern Maine have tested positive for EEE.
On Friday, Maine CDC Director Dr. Sheila Pinette said additional positive tests are likely.
“We still have plenty of warm weather ahead in the next few weeks and this increases the possibility of additional positive pools,” Pinette said in a news release issued Friday.
EEE is a virus that is transmitted through the bite of an infected mosquito. It can cause serious illness in humans, large animals like horses and some species of birds, according to Maine CDC.
In 2012, a flock of 30 farm-raised pheasants in Lebanon died from Eastern equine encephalitis. The state also recorded its first-ever human case of West Nile virus, another infection spread through the bite of an infected mosquito, in a Cumberland County man.
EEE is rarer than West Nile, but more deadly. The virus can cause inflammation of the brain and leads to death in 35 percent to 50 percent of cases. Last fall, a Vermont man died of EEE.
Other New England states have detected EEE and West Nile this summer. A New Hampshire man contracted two related viruses never before seen in the state — Powassan virus, which is transmitted through a tick bite, and Jamestown Canyon virus, a mosquito-borne pathogen that circulates widely in North America but doesn’t typically sicken humans.
“EEE is a very serious illness,” State Epidemiologist Dr. Stephen Sears said recently. “Mainers need to take appropriate precautions against mosquitoes to prevent this illness.”
Maine CDC recommends the following preventive measures to protect against EEE, West Nile virus and other mosquito-borne illnesses:
• Avoid spending time outdoors at dawn and dusk when many species of mosquitoes are most active.
• Use an EPA-approved repellent when outdoors, especially around dawn and dusk, and always follow the instructions on the product’s label.
• Wear protective clothing when outdoors, including long-sleeved shirts, pants and socks.
• Use screens on windows and doors to keep mosquitoes out of the home.
• Empty standing water where mosquitoes can breed, such as from flower pots, buckets and barrels.
Maine’s Health and Environmental Laboratory routinely performs testing for EEE and West Nile virus in mosquitoes, large animals and humans. Maine stopped testing individual dead birds for mosquito-borne illnesses in 2006 and no longer uses them as an indicator for disease.
Maine CDC will continue to provide updated information on mosquito-borne disease surveillance in Maine on a weekly basis. These reports are posted every Monday from May through September at http://www.maine.gov/dhhs/mecdc/infectious-disease/epi/vector-borne/arboviral-surveillance.shtml.
Future positive tests will be announced through this report.
Information on pesticides and repellents is available at the Maine Board of Pesticides Control website at http://www.maine.gov/agriculture/pesticides/public/index.htm#mosquito.