US OKS 3rd jab for those with low immunity

The US Food and Drug Administration authorised a third dose of Covid-19 vaccines from Pfizer and Moderna for people with compromised immune systems.

The amended emergency use authorization paves the way for people who have had an organ transplant, or those with a similar level of weakened immune system, to get an extra dose.

“After a thorough review of the available data, the FDA determined that this small, vulnerable group may benefit from a third dose of the Pfizerbiontech or Moderna vaccines,” Janet Woodcock, US FDA’S acting commissioner, said in a tweet on Thursday.

“Others who are fully vaccinated are adequately protected & do not need an additional dose of Covid-19 vaccine at this time.”

The vulnerable group of patients make up less than 3 per cent of US adults, Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC), had said before the authorisation.

A panel of advisers to the CDC will meet on Friday to discuss booster doses, and a vote later by the committee will help decide on the roll out of the extra shots.

Scientists are still divided over the broad use of Covid-19 vaccine boosters among those without underlying problems as benefits of the boosters remain undetermined.

Pfizer has said the efficacy of the vaccine it developed with Biontech drops over time, citing a study that showed 84 per cent effectiveness from a peak of 96 per cent four months after a second dose.