The state Department of Health is adopting the most recent COVID-19 guidance from the U.S. Centers for Disease Control and Prevention allowing a second booster shot for eligible residents.

Effective immediately, people who received their first booster shot at least four months ago may receive a second booster shot of a Pfizer or Moderna vaccine if they are over age 50.

People 12 or older who have a compromised immune system are also eligible for a second booster shot, as well as those who received primary and booster doses of the Johnson & Johnson vaccine.

“Additional booster shots allow people in these select populations to get extra protection against severe illness,” said Health Director Dr. Elizabeth Char in a news release Tuesday. “A second booster can be especially beneficial for people 65 and older and those 50 and older with underlying medical conditions.”

Kaiser Permanente Hawaii announced it anticipates administering second booster doses to members and nonmembers starting Tuesday. For a complete list of locations, visit kp.org/covid. For information on other COVID-19 vaccination and testing options, check hawaiicovid19.com.

The U.S. Food and Drug Administration also on Tuesday authorized an extra dose of the Pfizer or Moderna vaccine for Americans ages 50 and older, as well as for certain younger people with severely weakened immune systems.

The FDA said in a news release that emerging evidence suggests a second booster dose of an mRNA COVID-19 vaccine improves protection against severe COVID-19 and is not associated with new safety concerns.

“Current evidence suggests some waning of protection over time against serious outcomes from COVID-19 in older and immunocompromised individuals,” said Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, in the news release. “Based on an analysis of emerging data, a second booster dose of either the Pfizer-BioNTech or Moderna COVID-19 vaccine could help increase protection levels for these higher-risk individuals.”

Additionally, Marks said, “The data show that an initial booster dose is critical in helping to protect all adults from the potentially severe outcomes of COVID-19. So, those who have not received their initial booster dose are strongly encouraged to do so.”

In Hawaii, 76.8% of the state population has completed the primary series of COVID-19 vaccines, while 38.3% is boosted, according to DOH.

More than 550,000 doses of booster shots have been administered in the state so far, equating to about 55% of the state’s population eligible for a first booster shot.

“We strongly recommend the other 45% get their booster shot soon,” Char said. “Those now eligible for a second booster should determine the right time to get the extra protection another dose will provide. Anyone unsure about getting a second booster can consult their health care provider.”