New Hampshire resident dies from eastern equine encephalitis

The death follows the first human case of EEE in Mass. earlier this month.

An adult from Hampstead, New Hampshire, died from an eastern equine encephalitis virus infection, health officials announced Tuesday.

“EEEV is a rare but serious disease transmitted to people by infected mosquitoes,” a statement from the New Hampshire Department of Health and Human Services said. “DHHS offers our sympathies to the individual’s family and friends.”

The resident was hospitalized due to “severe central nervous system disease,” the statement said.

The death comes after Massachusetts officials announced the first human case of EEE in the state since 2020 earlier this month. The virus has no vaccine or antiviral treatment.

Massachusetts said Monday that 10 communities in the state have been raised to “high” or “critical risk” for EEE, and the state is spraying for mosquitos in parts of Plymouth and Worcester county this week.

“We have not seen an outbreak of EEE for four years in Massachusetts,” Massachusetts DPH Commissioner Robbie Goldstein, MD, PhD said in a statement. “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. We are asking everyone to do their part.”

So far this summer, health officials have identified the infection in one horse and seven mosquito batches in New Hampshire.

“We believe there is an elevated risk for EEEV infections this year in New England given the positive mosquito samples identified,” state epidemiologist Dr. Benjamin Chan said in a statement. “The risk will continue into the fall until there is a hard frost that kills the mosquitos.”

The last reported human EEE infection in New Hampshire was in 2014, which saw three human infections leading to two deaths, the department said. One out of the five people who contracted the virus in Massachusetts in 2020 died.

Cases of EEE occur “relatively infrequently,” according to the CDC, but people over 50 years old and under 15 are at greatest risk for developing severe disease.

EEE virus can cause flu-like symptoms such as fever, chills, muscle aches, and joint pain, as well as severe neurological disease, according to the health department.

One third of people who get encephalitis from EEE die, while many others experience life-long physical and medical impacts, officials say.

The department recommends that residents try to prevent mosquito bites by using repellents, wearing long sleeves and pants, ensuring doors and windows have tight-fitting screens, and avoiding being outdoors in the early morning and evening.

“In New Hampshire, mosquitos transmit infections including eastern equine encephalitis virus, West Nile virus, and Jamestown Canyon virus,” Chan said. “Everybody should take steps to prevent mosquito bites when they are outdoors.”