Younger people could be eligible to receive the Covid booster vaccine sooner, JCVI say.
Currently, those aged between 40-49 can book their booster jab appointment through the NHS Inform website.
People who are considered high risk, clinically vulnerable, over 50, and receive the flu vaccine have all been offered the the third vaccination against the coronavirus.
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Now, as a threat of a new strain sparks fears so close to Christmas, the Joint Committee on Vaccination and Immunisation (JCVI), said under-40s "should expect" to get the booster earlier than previously thought because of the Omicron variant.
First detected in South Africa, the new strain has double the mutations of the Delta virus, making scientists concerned that this will spread even faster and evade antibodies. The effectiveness of the vaccines against the new variant has not been clarified yet, and we expect more information within the coming weeks.
Already Scotland and countries around the world are enforcing rules and restrictions.
Scotland confirmed their red list that includes 10 countries from the African continent and England is reintroducing masks.
It has been proven that the effectiveness of the vaccines wear off over time, which is why there is now a push to get the third dose out.
Speaking on Radio 4's Broadcasting House, Professor Anthony Harnden, deputy chair of the JCVI, said those aged 18-39 could expect to get the booster jab earlier.
When asked if those aged 18-39 should brace for an extension to the booster programme on Radio 4's Broadcasting House, he said: "I think there's a very good, strong argument for raising the antibody level in the whole of the community.
"So, accelerating the booster programme, both by extending the age range and by reducing the interval between the second dose and the booster dose, will be an acceptable strategy."
When pushed on whether people aged 18 and over would be invited to get the booster sooner, he added: "Those adults 18 plus will have an offer of a booster earlier than we had previously envisaged."
Currently, there are no known cases of the Omicron variant in Scotland, but two have been found in the UK.
