WORCESTER—The Massachusetts Department of Public Health (DPH) reports the first human case of Eastern equine encephalitis (EEE) in the state this year.
The patient, a man in his 80s, was exposed in Worcester County. As a result, the risk level in the towns of Douglas, Oxford, Sutton, and Webster has been elevated to critical, with nearby Dudley, Northbridge, and Uxbridge now at high risk. Several other neighboring communities, including Auburn, Charlton, and Grafton, have been classified as moderate risk.
The season’s first EEE-positive mosquitoes were detected in Carver on July 3. Since then, EEE-infected mosquitoes have been found in several other areas across the state, including Plymouth, Bristol, Barnstable, Norfolk, Middlesex, and Essex counties.
“This is the first human case of EEE in Massachusetts since 2020,” said Public Health Commissioner Robbie Goldstein, MD, PhD, in the announcement. “EEE is a rare but serious disease, and it’s crucial that residents take precautions against mosquito bites, especially in areas with known EEE activity.”
Although EEE is rare, it is a serious and potentially fatal disease that can affect people of all ages. The virus is primarily transmitted to humans through the bite of an infected mosquito. In 2019, Massachusetts saw 12 human cases of EEE, resulting in six deaths. In 2020, there were five human cases and one death. There have been no human cases reported in the state from 2021 through 2023.
State Epidemiologist Dr. Catherine M. Brown emphasized the importance of preventive measures. “With EEE risk high in parts of Plymouth County and critical in parts of Worcester County, we strongly recommend using EPA-registered insect repellent, wearing protective clothing, and rescheduling outdoor activities to avoid peak mosquito hours between dusk and dawn,” she said in a statement.
Residents are urged to take steps to protect themselves from mosquito bites, such as using insect repellent, wearing long sleeves and pants, and ensuring that homes are mosquito-proof by repairing screens and eliminating standing water.
Pet owners should also take precautions, including removing standing water, keeping horses in stalls at night, and discussing vaccinations and mosquito repellents with their veterinarians. Suspected cases of EEE or West Nile virus in animals must be reported to the Department of Agricultural Resources and the DPH.
For more information on EEE and West Nile virus, including daily updates on positive test results, visit the DPH Arbovirus Surveillance Information web page or call the DPH Division of Epidemiology.
