The first person in the world to be given a fully-tested Covid-19 vaccine, 91-year-old Fermanagh woman Margaret Keenan, has urged people to get vaccinated, one year on from her shot.

Ms Keenan described receiving the Pfizer-BioNTech Covid-19 vaccine on 8 December 2020 as the "best thing that has ever happened". She was vaccinated in Coventry, where she has been living for more than 60 years.

"It was wonderful. I cannot believe it now, what happened at the time... I'm so happy I got the jab," Ms Keenan, known to friends as Maggie, said in a broadcast clip to mark the anniversary.

"I encourage everyone to have it."

British Prime Minister Boris Johnson hailed the UK's early success in rolling out Covid-19 vaccines and said it is why he was able to reopen England's economy in July.

He is now urging officials to scale up the country's ongoing booster programme to a similar level as the initial roll-out in light of concern over the new Omicron variant, which has also seen him reintroduce some mask mandates and travel restrictions.

"Vaccines remain our first and best line of defence against the virus," Mr Johnson said.

The UK has now given nearly 120 million doses of Covid-19 vaccine to its population of 67 million, either as first doses, second doses or as boosters.

Scientists are concerned that Omicron might be more transmissible than the currently dominant Delta variant and have mutations associated with lower vaccine effectiveness.

Health Secretary Sajid Javid has said that boosters should continue to offer good protection against severe disease even if shots are less effective against Omicron than previous variants.

May Parsons, the nurse who vaccinated Margaret Keenan, said a lot of people now seriously ill in her Covid-19 wards are unvaccinated.

"If you're unvaccinated, there is still a chance (to get a shot)," Ms Parsons said. "It's not too late."

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