CONCORD, N.H. – Despite announcing two new suspected cases of Eastern equine encephalitis, state health officials say they’re not worried about an epidemic.

A Concord man and a Manchester man were hospitalized over the weekend with suspected cases of the mosquito-borne illness. That comes on top of two confirmed cases found in patients from Londonderry and Goffstown.

“Triple E is clearly entrenched in New Hampshire,” said Elizabeth Talbot, deputy state epidemiologist. She said there may be additional cases this year, but “we are not anticipating a widespread epidemic.”

The disease, which starts with flulike symptoms, can trigger brain inflammation that can be fatal in some cases.

According to the Centers for Disease Control, the virus kills about one-third of those infected. The CDC reports a total of 200 confirmed cases in the U.S. since 1964, with an average of four each year.

Last year, there were six cases nationwide, four of them in Massachusetts. Three people died.

“Yes, it is unusual for our state to be looking at four possible cases in one year,” Health Commissioner John Stephen said. “Obviously, we’ve been tracking cases for a number of years. But it’s not unusual if you consider last year there were four cases confirmed in Massachusetts.”

Talbot said scientists have yet to understood how the virus survives the winter and why it flares up at certain times and in certain places. “It is likely that we need to anticipate the presence of this disease next season as well,” she said.

Health officials are recommending people use insect repellent containing DEET, wear protective clothing and get rid of standing water where mosquitoes can breed.

Triple E tends to strike in cycles, most often in swampy, lower-populated areas along the Eastern Seaboard. States with the most confirmed cases historically have been Massachusetts, New Jersey, Florida and Georgia.