The highly contagious mumps virus hanging in Hawaii’s air has so far resulted in 47 cases — a 16-year high.

The best way to avoid the disease: Get vaccinated. For children that means two doses of the Measles, Mumps, and Rubella (German measles) vaccine, with the first dose given at age 12–15 months and the second at 4–6 years of age.

Some adults should get the MMR vaccine, too. Generally, anyone age 18 or older and born after 1956 should get at least one dose unless they can verify childhood vaccinations or have had all three diseases, according to the Centers for Disease Control and Prevention (CDC).

With Hawaii’s public schools soon breaking for summer vacation, fortunately, children will be less likely to spread the virus, which can make a patient miserable for one week or longer with fever, headache, muscle pain, loss of appetite and the signature symptom: swollen salivary glands under the ears, leaving the jaw tender. (Among the rare complications caused by mumps: deafness, encephalitis and meningitis.)

Adults should take note that 21 of the cases reported so far are adults, including many who have no connection to schools, the state Department of Health said.

Two MMR doses are about 97 percent effective at preventing measles, and a single dose is equally effective at preventing rubella. With the mumps vaccine, though, you’re less than bulletproof. Two doses are 88 percent effective, officials say.

Consequently, in the decades following the start of the U.S. mumps vaccination in 1967, there was typically a flurry of cases each year, from a few hundred to a few thousand. But in recent years, the numbers have increased — more than 5,000 cases were reported last year in the United States, the most in a decade.

The CDC has tied some of this year’s nationwide count — more than 2,570 cases of mumps through April — to last year’s spike. Officials are investigating factors that may have contributed to the 2016 outbreak, and whether a third dose of mumps vaccine should be added to the regular vaccination lineup.

There’s some question regarding whether the vaccine’s effectiveness decreases over time because outbreaks have been occurring in places where residents had already received both recommended doses, such as mainland college campuses. In some instances, such as when 317 cases hit the the University of Illinois at Urbana-Champaign during the 2015-16 school year, health officials recommended a third dose. No such move is in the works in Hawaii at this time.

Dr. Marian Melish, professor of pediatrics at the University of Hawaii’s John A. Burns School of Medicine, said: “Even if there were 200 cases in a population of 1 million, that’s not too amazing.” So far, none of the cases in the islands this year — 46 on Oahu, and one on Kauai— have resulted in hospitalization.

Even so, don’t let your guard down. Take a look at your vaccination records, and contact your doctor or a health care provider if you have questions or concerns.

Before the vaccine was first offered, 50 years ago, the virus was endured as a “universal childhood disease,” with roughly 200,000 cases reported annually. Officials say about 90 percent of Hawaii’s schoolchildren are now vaccinated for mumps.

For the sake of everyone’s health and wellness in the islands, we must take care to be vigilant of vaccination-related recommendations and follow through with getting shots.