LONDON - COVID-19 vaccines have saved more than 112,000 lives and averted 24 million cases of the disease, British officials said on Tuesday as they recommended all vulnerable people, frontline health staff and those aged over 50 be offered a booster shot.

The Joint Committee on Vaccination and Immunisation's recommendation of a third dose six months after a second shot, paves the way for a broad revaccination programme in Britain, which has one of the world's highest death tolls from COVID-19.

It comes ahead of an announcement by the government on its strategy for taming infections this winter, with Prime Minister Boris Johnson and other officials warning that the battle against the virus was not over.

"Our latest estimates are that since we began deploying these vaccines, they've probably averted in the region of 24 million cases of COVID in the UK and 112,000 deaths - so incredibly successful to date and remains so," England's Deputy Chief Medical Officer Jonathan Van-Tam told reporters.

"We're not past the pandemic. We know this winter could quite possibly be bumpy at times."

The government has already indicated it would scrap plans for vaccine passports to be required to get into nightclubs, end some of its emergency COVID powers and use lockdowns only as a last resort. 

Instead, Johnson will lean on vaccines and testing to try and contain COVID-19 heading into autumn and winter.

"The pandemic is far from over, but thanks to our phenomenal vaccine programme, new treatments and testing we are able to live with the virus without significant restrictions on our freedoms," Johnson said in a statement.

Britain has officially recorded 134,000 COVID-19 deaths, and more than 7 million cases. So far 44 million people have had two vaccine doses, 81 percent of those aged over 16. On Monday, the government said those aged 12 to 15 would also be offered shots.

Johnson scrapped the last coronavirus restrictions in England in July, citing the more favourable conditions of the school summer holidays as he eyed what he characterised as a "return to normal". 

The JCVI had already given interim advice that elderly and vulnerable people would be the priority for any booster programme, and that it could start in September. 

It said its preference was that the Pfizer vaccine was used for the booster dose, or alternatively a half-dose of a Moderna shot. Britain ordered 60 million additional Pfizer doses for the booster programme in April. 

Professor Lim Wei Shen, chair for COVID-19 immunisation on the JCVI, said their advice for a booster dose did not imply that there would be a requirement for a shot every six months.

He also said not everyone under 50 years old would require another shot.

Its recommendation comes after some leading scientists, including from the U.S. Food and Drug Administration and World Health Organisation, said in an article in the Lancet medical journal on Monday that COVID boosters were not yet needed for the general population.

(Reporting by Alistair Smout, Michael Holden and Guy Faulconbridge; Editing by Bill Berkrot and Philippa Fletcher) ((alistair.smout@thomsonreuters.com; +44 207 542 7064; Reuters Messaging: alistair.smout.thomsonreuters.com@reuters.net))