The government has committed to offering everyone a booster shot of the COVID vaccine by the end of December - but how do you book one?

In early December the government said everyone over the age of 18 could get a COVID vaccine booster amid fears of the then recently emerged Omicron variant.

On 12 December the government moved again to bring forward the goal of offering everyone a booster by the end of January to the end of December and allowed the NHS to cancel certain non-vital appointments in order to focus on the rollout.

Read more: Omicron multiplies 70 times faster than Delta in airways, says Hong Kong study

Since then an army of volunteers and over 500 military personnel have been deployed to help speed up the programme.

Why is a booster needed?

A booster jab will top up the immunity of those already fully inoculated against the virus.

The NHS said a booster jab will help improve the protection you have from your first two doses of the vaccine, helping to give you longer-term protection against getting seriously ill from COVID-19.

It is believed the effectiveness of the jabs deteriorate over time and any new variants could find ways of getting around the vaccines.

Does a booster make a big difference?

Pfizer and BioNTech have both said a booster will have a dramatic effect on efficacy.

A trial by Pfizer found that during the study period, there were five cases of COVID-19 in the booster group, and 109 cases in the non-boosted group.

Watch: How the world could be better after COVID

A booster dose given to patients who had the initial two jabs showed a relative vaccine efficacy of 95.6% when compared with those who did not receive a booster.

When can you get a booster?

Boosters are available to all people in the UK aged 18 and over.

People who are over the age of 16 and are at risk, live with someone who is at risk, or care for someone at risk can also get a booster.

You must have had your second dose of the vaccine at least three months ago.

Pregnant people can also get one.

How do you get a booster?

There are four ways to get a booster, firstly if you work for the NHS they should offer you one while at work.

Alternatively, you can book an appointment through the NHS website where you will be offered a variety of times and locations to get the jab.

Read more: COVID-19: What the data tell us about the spread of Omicron

Another method is to go to a walk-in vaccination centre - these can usually be found on your local NHS website/ social media or via the local press.

The final way is to wait for your GP to contact you and arrange an appointment with them.

Will boosters be needed for COVID passes and holidays?

Health Secretary Sajid Javid has said COVID passes will be updated to require everyone to have had a third jab in order to get one once everyone has had adequate time to get their booster.

Similar rules will likely apply in Scotland, Wales and Northern Ireland.

Currently, people who have had two doses of the vaccine do not have to self-isolate when they return from a non-red listed country, but it is likely this will be updated to require three doses.

Some countries have also begun setting "expiry dates" on vaccination status, meaning they will require people to have had a dose within a certain amount of time in order to enter their nation.

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