Covid booster jabs will be available to millions more people in England from tomorrow (12 December).
Everyone aged 30 to 39 will be able to book an appointment to get their third vaccine - as long as it is three months on from their second dose.
The move comes amid concerns the UK is facing a major wave of infections in January from the Omicron variant.
How to book your Covid booster jab - and who is eligible
There are around 7.5 million people aged 30 to 39 in England.
Approximately 3.5 million of those are eligible for boosters from Monday, NHS England said.
All eligible adults can book their booster jab two months (61 days) after their second dose.
However, the third jab has to take place three months (91 days) on from their second dose.
To get an appointment, all eligible people can use the NHS national booking system or attend a nearby walk-in centre.
Does the booster jab protect against the Omicron variant?
Analysis by the UK Health Security Agency (UKHSA) found that the AstraZeneca and Pfizer vaccines provided “much lower” levels of protection against symptomatic infection with Omicron compared with Delta.
However, the agency said that a booster dose gives around 70% to 75% protection against symptomatic infection with Omicron, as it urged people to have their boosters.
How many people have Omicron in the UK?
Figures released on Saturday (11 December) showed there had been an additional 633 confirmed cases of the Omicron variant reported across the UK.
A breakdown of the data showed there had been a further 618 confirmed cases in England, 11 in Scotland, two in Wales and two in Northern Ireland.
That takes the overall UK figure, as of Saturday, to 1,898 confirmed cases - which was up 50% on Friday’s figure when the total was 1,265.
What has the Government said about the booster jabs?
Health and Social Care Secretary Sajid Javid said: “The Covid-19 booster programme is accelerating rapidly and more than 22 million people in the UK have already received their top-up, securing vital protection ahead of Christmas.
“This is our national mission – the most recent data shows boosters are the essential defence against Omicron and we are doing everything in our power to get jabs into arms as quickly as possible.
“We are now expanding the offer to over-30s, so please come forward as quickly as possible to get boosted and help our country get ahead in this race with the variant.”
What restrictions are in place to tackle the Omicron variant?
The Prime Minister announced earlier this week that he would be triggering his winter Plan B protocols in a bid to fight the Omicron variant.
That means vaccine passports to be made mandatory for large venues, face masks to be worn in most indoor venues and guidance issued that people should work from home if possible.
Some Tories have reacted with dismay to the plans, with more than 60 Conservative MPs said to be against the imposition of extra coronavirus measures.
There will be a vote on the measures in the House of Commons this coming week - which will almost certainly pass as Labour supports the plans.
There have also been reports about a Plan C which could be introduced if Omicron continues to spread.
No 10 has maintained there are “no plans” to go further with measures in England, amid reports that proposals are being drawn up for a Plan C, featuring even tougher rules.
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