In response to the growing threat of the eastern equine encephalitis (EEE) virus, parts of Norton and Rehoboth and all of Dighton will be sprayed for mosquitoes, officials have announced.
Massachusetts Department of Agricultural Resources is conducting and monitoring aerial spraying in specific areas of Bristol and Plymouth counties beginning Thursday night and continuing over several evenings.
The spraying is weather dependent and it was not clear when spraying would be conducted in area towns.
“Based on the findings this year combined with our experience with EEE, it is important to use aerial spraying to help reduce public risk,” Public Health Commissioner Monica Bharel said in a new release Tuesday. “While aerial spraying can reduce the threat of mosquito-borne illness, it cannot eliminate the risk altogether.”
Officials will continue to monitor the area over the next two weeks and plan to conduct a second round of spraying to achieve maximum effectiveness.
“The swamp habitats that are the source of EEE activity are not accessible by truck-mounted ground sprayers and so aerial applications are warranted when the risk is this high,” DPH State Epidemiologist Catherine Brown said.
Bristol County Mosquito Control Project, which is based off Forest Street in Attleboro, is helping to coordinate the spraying.
The state Department of Public Health has raised the risk level for EEE in many communities in southeastern Massachusetts.
Rehoboth and Dighton are now at high risk. Easton, which borders Norton and Mansfield, is also in that category. Attleboro, Norton and Seekonk are at moderate risk.
The only area community entirely within the spray zone is Easton. Those partially within the zone include Norton, Easton and Rehoboth.
Those who live entirely or partially within the spray zones do not have to take any special precautions before aerial spraying begins, according to DPH.
While less than an ounce of the pesticide Anvil 10+10 will be sprayed per acre, an amount considered safe, health officials advise area residents to bring pets indoors and cover ornamental ponds.
EEE virus has been found in 164 mosquito samples this year and half of them are from species of mosquitoes capable of spreading the virus to people. No human or animal EEE cases have been detected this year.
The virus has become widespread in an area of Massachusetts that historically sees the most EEE activity. The risk level was raised because there is more activity than typically seen and it was happening early in the season, DPH officials said.
August is when there is the highest chance of EEE infection in humans, according to DPH officials. But mosquitoes can be active and a threat into fall, and they also carry the dangerous West Nile virus, authorities say.
Area residents are advised to apply insect repellent and wear long-sleeve shirts, long pants and socks when outdoors, eliminate standing water and install/repair screens.
They’re also advised to reschedule evening outdoor events to avoid the hours between dusk and dawn when mosquitoes are most active.
The state Department of Conservation and Recreation has canceled evening programming at state parks in the area until the EEE risk levels decrease. The state parks include Dighton Rock State Park, Myles Standish State Forest in Plymouth and Carver, and Rehoboth State Forest.
Communities in the New Bedford area this week have canceled events and ended others early. In Rochester, all beaches, parks, ballfields and town events are closing 30 minutes before dusk.
EEE is a rare but serious and potentially fatal disease that impacts the brain and can affect people of all ages. It occurs sporadically in Massachusetts, with the most recent outbreaks occurring from 2004-2006 and 2010-2012. There were 22 human cases of EEE infection during those years, with over half in Bristol and Plymouth counties. The last human case of EEE in Massachusetts occurred in 2013.
Residents are encouraged to visit the DPH website at www.mass.gov/guides/aerial-mosquito-control-summer-2019 for the latest updates on spraying in their communities.
For questions about mosquito control in your city or town, contact your local board of health.