In the biggest outbreak of mumps in Alaska in decades, 44 people have been confirmed with the illness and many others show signs of it, the state Division of Public Health said Wednesday in a bulletin recommending additional vaccinations for at-risk groups.

The outbreak is centered in Anchorage and is strongly hitting the city's Pacific Islander and Native Hawaiian populations. Also at risk are people who have recently been in group settings where the highly contagious sickness is circulating, the bulletin said.

"It's important for everyone living in Anchorage to take this outbreak seriously," especially those at-risk groups, said Joe McLaughlin, state epidemiologist.

The illness causes headaches, fever, swollen salivary glands under the jaw and puffy cheeks. In rare cases it can lead to more dangerous complications, including deafness or meningitis that can swell brain tissue, he said.

"It's not life or death, but it's no fun to have the mumps," said Bruce Chandler, chief medical officer with Anchorage's Department of Health and Human Services.

The Alaska and Anchorage health agencies began investigating mumps cases in May when the first case was reported. The number of cases has been steadily growing since then.

"While the original source of the outbreak is uncertain, several of the initial patients reported recent travel to or close contact with a person who had recently traveled to a Pacific island where mumps is circulating," the bulletin said.

Of the 44 cases confirmed in the laboratory, the median age of the person afflicted is 24, and 82 percent are Native Hawaiian or other Pacific Islander, the bulletin said.

Two people from those confirmed cases, both adults, have been hospitalized, McLaughlin said. He did not provide information about the condition of the adults Wednesday.

"No one has died," he said.

Those confirmed cases, and 12 "probable" cases, involved Anchorage residents or people who spent a lot of time in Anchorage, the bulletin said.

Also, another six people are suspected of having mumps, based on symptoms.

The last mumps outbreak in Alaska was in 1995 in Kodiak, when 10 people were infected, McLaughlin said. An outbreak similar in scale to the current one hasn't been seen since 1974, when 42 cases of mumps were reported to state health officials.

Nationwide, mumps cases have risen sharply in recent years, McLaughlin said. Cases jumped from 229 in 2012 to 5,833 in 2016, he said.

That's well below the nearly 200,000 cases recorded yearly before Americans started getting vaccinated for mumps in 1967, he said.

Two mumps vaccinations were once thought to be enough, McLaughlin said. But the immunity from two doses, which many adults received as children, can diminish with time.

Chandler, with the municipality, said it's "reassuring that even though we had certain people with mumps in school we haven't seen widespread transmission to other students." That's likely because students have had two doses, and nearly 90 percent of those students should be immune, he said.

As part of the outbreak, the bulletin recommends a third dose for Native Hawaiian and Pacific Islanders, if it has been five years or longer since the second vaccination. The recommendation also applies to anyone who may have been part of group settings where mumps are circulating. That's consistent with new national guidelines, McLaughlin said.

Most Alaskans in need of a third dose are eligible for state-supplied vaccinations, he said. Medicaid will also cover the recommended third dose.

People experiencing mumps-like systems, which include muscle ache and fatigue, should "self-isolate" at home and stay away from work or school, McLaughlin said. To prevent mumps from spreading, sick people should avoid close contact with others for at least five days after salivary glands begin to swell.

Mumps is often spread when people sneeze or cough, or as they touch surfaces contaminated with saliva or mucus droplets.