The Food and Drug Administration on Monday approved updated booster shots for COVID-19, a major step toward launching a fall immunization campaign against the virus that is now viewed as a perennial but manageable threat.

Regulators said the shots from Pfizer and Moderna are tailored to combat the XBB.1.5 variant that began circulating earlier this year and will replace the “bivalent” shots that were introduced last fall.

The updated shots will be manufactured in a similar manner as previous versions and the approval is based on immune response data in lab conditions, according to the FDA.

“The public can be assured that these updated vaccines have met the agency’s rigorous scientific standards for safety, effectiveness, and manufacturing quality. We very much encourage those who are eligible to consider getting vaccinated,” said Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research.

Persons aged 5 years and older can get a single dose of an updated vaccine at least two months after the last dose of any COVID-19 vaccine, regardless of their previous vaccination.

Advisers to the Centers for Disease Control and Prevention are scheduled to meet Tuesday to discuss the updated boosters and recommendations for who should get them.

Some health professionals think recommendations should be tailored toward at-risk populations instead of a blanket recommendation to get boosted each year.

Nearly seven in 10 Americans received a two-dose primary series of a COVID-19 vaccine. But additional shots have been a tougher sell, with only 17% of the population receiving the booster unveiled last fall.

The vaccines were developed in record time during the first year of the pandemic. The main options from Pfizer and Moderna deploy messenger RNA, which teaches the body how to recognize the virus and mount an immune response. The shots haven’t been able to block infection and transmission outright, and are mainly viewed as tools to limit serious disease.

The coronavirus continues to mutate, so drugmakers are trying to fine-tune the shots to match circulating strains as best as possible, akin to updated flu shots.

For more information, visit The Washington Times COVID-19 resource page.

• Tom Howell Jr. can be reached at thowell@washingtontimes.com.