Massachusetts Braces for Eastern Equine Encephalitis: Mosquito-borne Virus Alert

As the summer draws to a close, Massachusetts finds itself grappling with a rare yet dangerous mosquito-borne virus known as eastern equine encephalitis (EEE). In response to the escalating risk of infection, officials have moved swiftly to implement precautionary measures, including the closure of public parks and targeted pesticide spraying in several communities across the state. EEE is a serious viral disease transmitted to humans primarily through the bite of an infected mosquito, as outlined by the Centers for Disease Control and Prevention (CDC). While the disease can affect individuals of any age, it poses the most significant threat to children under 15 and adults over 50. With a staggering mortality rate of approximately 30% among those infected, EEE can lead to severe neurological complications for those who survive. Currently, 13 communities in Massachusetts are identified as being at heightened risk. The Massachusetts Department of Public Health (DPH) announced plans for aerial and truck-based spraying of pesticide to mitigate mosquito populations in these at-risk areas. This week, aerial spraying will commence in Plymouth County, while targeted truck spraying will take place in parts of southern Worcester County. The emergence of a human case in a man in his 80s—the first reported since 2020—has heightened concerns over the virus's return. Previous years had seen multiple cases, including five human infections and one death in 2020, and 12 infections with six fatalities in 2019. "We have not seen an outbreak of EEE for four years in Massachusetts," said Robbie Goldstein, commissioner of the Massachusetts DPH. "This year's outbreak and activity raise the risk for communities in parts of the state. We need to use all our available tools to reduce risk and protect our communities." To further safeguard residents, health officials have urged the public to take personal precautions. They recommend that individuals stay indoors during peak mosquito activity hours, apply insect repellent when venturing outside, eliminate standing water where mosquitoes breed, and ensure that screens on windows and doors are intact. Reflecting the seriousness of the situation, the town of Plymouth has taken proactive steps by closing its public outdoor recreation facilities from dusk until dawn following the infection of a horse in the area. Residents have been cautioned to limit outdoor activities during evening hours to reduce their exposure. While the state prepares for targeted spraying, it is important to note that such measures will not completely eliminate the risk of infection. EEE does not occur annually, but experts warn that based on current evidence, a high risk of human cases is anticipated in 2024. There are currently no vaccines available to prevent EEE, making public awareness and personal protective measures crucial in the fight against this potentially lethal disease. As Massachusetts navigates this health threat, the collaboration between state officials, public health agencies, and local communities will be essential in protecting residents and reducing the risk of infection. As we move deeper into fall, vigilance will be key in preventing the spread of this rare but serious disease.