AMESBURY — Months before the first mosquitoes of the year pester Greater Newburyport residents, local and state health officials are spreading the word that West Nile virus and Eastern equine encephalitis, potentially deadly diseases carried by the insects, are here to stay and should be considered a yearly concern.
Earlier this week, health officials informed the state’s public health council that West Nile virus and Eastern equine encephalitis can be expected every year and no longer should be considered a surprise or an emergency.
Eastern equine encephalitis, or EEE, is a rare but deadly mosquito-borne illness. The virus can infect people of all ages, but typically people younger than age 15, over age 50, or who have weaker immune systems are most at risk of serious illness. Over the last few years, EEE has infected people in a geographically larger part of the state with a potential hot spot emerging in communities along the New Hampshire border.
According to health officials, an uptick in the number of EEE and West Nile cases in 2012 prompted the state to begin increasing communication with municipalities and lowering the risk threshold for taking actions, such as curtailing evening, outdoor activities. EEE is riskiest for young children, while West Nile generally sickens older people, and many people infected by West Nile will only have a low-level illness.
EEE was first recorded in Massachusetts in 1938, and has historically been concentrated in Norfolk, Plymouth and Bristol counties, though in recent years it has occurred in the Connecticut River Valley. West Nile is more concentrated in population centers.
Locally, the announcement came as little surprise.
Amesbury and Salisbury health agent Jack Morris said he has been experiencing detection of those two diseases each year.
“It is a virus in the environment that is here to stay, similar to the migration of rabies,” Morris said.
As mosquito season returns, Morris said communities will continue to practice the same approach.
“When we have a virus isolation, we will alert the public and take appropriate actions,” Morris said. “The public should be cautioned that these viruses are here and proper personal protection should be used when mosquito season hits.”
Last August, Amesbury health officials announced that mosquitoes carrying West Nile virus were collected in Amesbury, prompting targeted mosquito spraying in the northwest section of the city where the virus was found. A month later, mosquitoes carrying EEE were found in the city, leading to another round of spraying.
Amesbury and Salisbury are members of Northeast Mosquito Control, which conducts a region-wide spray of both communities in an effort to kill off as many potentially infected mosquitoes as possible. Officials have noticed a significant drop in mosquito activity after spraying.
Information from the State House News Service was used in this report.