Covid booster jabs should be offered to all over-18s to help stop a potential wave driven by the new variant Omicron, UK government advisers say.
The Joint Committee on Vaccination and Immunisation said the minimum gap between the second dose and booster should also be reduced to three months.
The experts said boosters should be prioritised in order of vulnerability.
And they recommended children aged 12 to 15 should be invited for a second jab three months after their first.
The JCVI also recommended severely immunosuppressed people should be offered a fourth dose of the vaccine as a booster. They are currently receiving three jabs.
England's deputy chief medical officer Professor Jonathan Van-Tam told a Downing Street briefing that Omicron was the "new kid on the block" "and it has "always been the case that, at some point, we are going to get a variant that gives us heightened concern".
He said: "With any vaccine during a pandemic, we get the greatest benefit for individuals and society if the vaccine is deployed before the wave starts. We want to provide boosters early enough... before any possible wave."
The advice has been given to ministers in all parts of the UK. The JCVI only gives recommendations and the final decision on measures to combat Covid lies with the politicians.
In its advice, the JCVI, also said it would continue to review data on the potential benefits and risks of offering the Covid vaccine to children aged 5 to 11.
Early evidence suggests the new Omicron variant - initially reported to the World Health Organization from South Africa on Wednesday - has a higher re-infection risk.
Eleven cases of the Omicron variant have now been detected in the UK. The UK Health Security Agency said the latest two found have links to travel in southern Africa. They were detected in the Camden and Wandsworth areas of London.
Prime Minister Boris Johnson has unveiled new rules on face masks and isolation to contain the spread of the new variant that are due to come in to force in England on Tuesday.
Addressing MPs in the House of Commons on the government response to the Omicron variant, Health Secretary Sajid Javid said the JCVI's latest advice on boosters and vaccinations would be adopted for people in England.
https://www.bbc.co.uk/news/uk-59465577
The Joint Committee on Vaccination and Immunisation said the minimum gap between the second dose and booster should also be reduced to three months.
The experts said boosters should be prioritised in order of vulnerability.
And they recommended children aged 12 to 15 should be invited for a second jab three months after their first.
The JCVI also recommended severely immunosuppressed people should be offered a fourth dose of the vaccine as a booster. They are currently receiving three jabs.
England's deputy chief medical officer Professor Jonathan Van-Tam told a Downing Street briefing that Omicron was the "new kid on the block" "and it has "always been the case that, at some point, we are going to get a variant that gives us heightened concern".
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He said: "With any vaccine during a pandemic, we get the greatest benefit for individuals and society if the vaccine is deployed before the wave starts. We want to provide boosters early enough... before any possible wave."
The advice has been given to ministers in all parts of the UK. The JCVI only gives recommendations and the final decision on measures to combat Covid lies with the politicians.
In its advice, the JCVI, also said it would continue to review data on the potential benefits and risks of offering the Covid vaccine to children aged 5 to 11.
Early evidence suggests the new Omicron variant - initially reported to the World Health Organization from South Africa on Wednesday - has a higher re-infection risk.
Eleven cases of the Omicron variant have now been detected in the UK. The UK Health Security Agency said the latest two found have links to travel in southern Africa. They were detected in the Camden and Wandsworth areas of London.
Prime Minister Boris Johnson has unveiled new rules on face masks and isolation to contain the spread of the new variant that are due to come in to force in England on Tuesday.
Addressing MPs in the House of Commons on the government response to the Omicron variant, Health Secretary Sajid Javid said the JCVI's latest advice on boosters and vaccinations would be adopted for people in England.
https://www.bbc.co.uk/news/uk-59465577