LONDON (BLOOMBERG) - The British government is extending its coronavirus booster programme, part of an effort to avoid following other European nations into imposing new restrictions to control the virus.

From Monday (Nov 22), everyone over the age of 40 will be invited to have a third dose of the vaccine.

Health Secretary Sajid Javid said the hope is that by bolstering immunity within the population, the number of serious cases that require hospitalisation will be limited. Britain has already delivered 15 million booster jabs covering a quarter of the population.

"It's very sad to see cases rising, surging, in certain parts of Europe," Mr Javid said in an interview with Trevor Phillips on Sky News on Sunday.

"What's made a real difference here in Britain, is our booster programme."

Germany, Austria and the Netherlands are among the countries where a recent surge in cases has alarmed the authorities, prompting another round of curbs on activity.

For now, there's optimism that Britain won't have to follow suit, partly because infections jumped during the summer and early autumn after the government allowed the virus to run basically unchecked.

Cases jumped after Prime Minister Boris Johnson removed restrictions in mid-July, while Covid-19-related fatalities are currently running at more than 1,000 a week.

"We are looking with grave concern and trying to determine whether there are differences in the situation in Europe or whether it's just a matter of time until this faces us here," behavioural scientist Linda Bauld, from the College of Medicine at the University of Edinburgh, said on Sky News.

Professor Andrew Pollard at the Oxford Vaccine Group, told BBC News that "it's unlikely that we're going to see the very sharp rise" in infections that much of the rest of Europe is suffering now.