The US Food and Drug Administration is close to making a decision on authorisation of a second dose of updated Covid-19 vaccine boosters for high-risk people, the Wall Street Journal reported on Tuesday, citing sources.

FDA officials could make the decision within a few weeks, the WSJ said, adding that the regulator is considering authorising second jabs of Omicron-targeted shots for people who are 65 years and older or those who have weakened immune systems, although officials are yet to reach a final decision.

The agency continues to closely monitor the emerging data in the United States and globally, and that data will dictate any decision on additional updated boosters, the FDA said in a statement.

The Centers for Disease Control and Prevention (CDC) would have to recommend the shots after the FDA authorises the second Omicron-tailored boosters from Pfizer-BioNTech/ and Moderna for them to become widely available.

The decision comes at a time when the FDA plans to shift to an annual Covid-19 booster campaign with an updated strain, similar to the way Americans get their flu shots.

Updated boosters have helped prevent symptomatic infections against the new XBB-related subvariants, according to data released by the CDC in January.

The FDA authorised the so-called bivalent Covid-19 boosters in August that target the BA.4 and BA.5 Omicron subvariants, along with the original strain of the coronavirus. Rollout of the updated boosters in the United States started the following month.

As of March 15, around 54 million bivalent vaccine doses were administered, accounting for 16.4 percent of the US population, according to government data.

- Reuters