People aged 18 and up who received Moderna boosters at least five months ago are now eligible to get a third shot to help protect them against Covid-19.

The Hawaii Department of Health announced the news Tuesday. The change reflects a new recommendation from the Centers for Disease Control and Prevention issued Friday.

Public health officials nationally and in Hawaii have increasingly emphasized the importance of receiving boosters, particularly to prevent against the omicron strain of the coronavirus.

Adults who received at least two shots of the Pfizer vaccine are eligible for a booster after five months. Children aged 12-17 who received Pfizer vaccines are also eligible for boosters after five months.

Adults who received one shot of the Johnson & Johnson vaccine are eligible for a booster after two months.

Health officials say waning immunity over time underscores the importance of receiving third shots to prevent against severe illness from Covid.

Most people who are hospitalized from Covid in Hawaii are unvaccinated, but between 30-40% of Covid hospitalizations include people who received at least two shots of Pfizer or Moderna or one shot of Johnson & Johnson’s vaccine.

Lt. Gov. Josh Green, an emergency room physician, said that he believes 80% of the people who are vaccinated and hospitalized with Covid could have avoided hospitalization had they received boosters.

Hawaii reported nearly 3,000 new Covid cases Tuesday, with a statewide test positivity rate exceeding 21%.