Fourth Covid vaccines are not currently needed, government scientific advisers have said, amid increasing evidence that the omicron strain is much milder than previous variants.

On Friday night, the Joint Committee on Vaccination and Immunisation (JCVI) announced that booster jabs continue to provide high levels of protection against severe disease from omicron in older adults, including the most vulnerable.

The committee’s analysis found that, three months after receiving a third jab, protection against hospitalisation among those aged 65 and over remains at around 90 per cent.

Ministers have been exploring the possibility of a fourth jab for several weeks after Israel, considered a global pioneer in Covid vaccination, launched such a programme last month.  

But Prof Wei Shen Lim, the JCVI’s chairman of Covid immunisation, said: “The current data show the booster dose is continuing to provide high levels of protection against severe disease, even for the most vulnerable older age groups.

“For this reason, the committee has concluded there is no immediate need to introduce a second booster dose, though this will continue to be reviewed.”

It comes as Covid numbers in Britain fell for a third day in a row and evidence emerged that hospitalisations arising from virus cases were 12 times lower than during last year’s winter peak.

There were 178,250 cases reported in the UK on Friday, down from 179,756 the previous day and a daily fall of more than 11,000 from the previous week.

New figures from Scotland show that just one per cent of people who test positive for Covid are ending up in hospital – down from 12 per cent last January. 

Data from England show that the number of patients in mechanical ventilation beds has fallen to 728 – a decline of 63 in a week and the lowest it has been since October.

Speaking during a visit to King’s College Hospital in south London, Sajid Javid, the Health Secretary, said: “When we look at omicron versus the previous variants, of course there are some encouraging signs. We know now that omicon is less severe.”

However, Mr Javid emphasised the need for people to come forward for their booster jabs amid “challenging times” for the NHS.