A New Hampshire resident who tested positive for the mosquito-borne infectious disease Eastern equine encephalomyelitis has died, state health officials said.

The Hampstead resident’s infection is the first in the state in 10 years, the New Hampshire Department of Health said Tuesday. The resident, whom the department identified only as an adult, was hospitalized for severe central nervous system symptoms, the department said.

About one-third of people who develop encephalitis from the virus die from the infections, and survivors may suffer lifelong mental and physical disabilities. There is no vaccine or antiviral treatment. According to the U.S. Centers for Disease Control and Prevention, there are about 11 cases of Eastern equine encephalomyelitis in humans each year in the United States.

Read more: What you should know about the rare but deadly mosquito-borne virus in US cities

In 2014, there were three human cases of the virus in New Hampshire, two of which were fatal. The health department said the rare but dangerous virus was also detected in a horse and several mosquito swarms in New Hampshire this summer.

The virus has also emerged in neighboring states this summer, with cases in people in Massachusetts and Vermont, the New Hampshire health department said. The virus can cause flu-like symptoms and can also lead to severe neurological disease and inflammation of the brain and the membranes surrounding the spinal cord.

“Given the positive mosquito samples, we believe there is an increased risk of EEEV infection in New England this year. The risk will persist into the fall until a hard freeze occurs to kill the mosquitoes. Everyone should take steps to avoid mosquito bites when outdoors,” said state epidemiologist Dr. Benjamin Chan.