New York, Mar 27 (IANS): The US government is expected to give older adults over the age of 50 the option of getting a second Covid-19 vaccine booster as early as next week.

Two sources familiar with the government's plans said the Food and Drug Administration (FDA) is planning to authorise a fourth dose of the Pfizer and Moderna mRNA vaccines for adults over age 50 next week, reports CNN.

The Centers for Disease Control and Prevention (CDC) is expected to follow soon after with what's known as a permissive recommendation, which means that the shots will not be officially recommended but may be given to people who want them, said a source who spoke to CNN.

The decision to make fourth doses available now will bypass independent groups of scientific advisers for both the FDA and CDC, which would normally meet and publicly review the available science and then make recommendations to the agencies.

Eric Topol, a cardiologist who is director of the Scripps Translational Research Institute in California, said the decision was expected next week, ahead of an April 6 meeting of the Vaccines and Related Biological Products Advisory Committee (VRBPAC), a group of independent experts who advise the FDA on its vaccine decisions.

Boosters are on the agenda for discussion at that meeting, which will focus on future planning for boosters and variant-specific vaccines.

Topol, who was apprised of the FDA's plans, said it was his understanding that the change would apply to both the Pfizer/BioNTech and Moderna vaccines.