Margaret Keenan, a 90-year-old grandmother, on Tuesday became the first person in the world to receive the Pfizer COVID-19 vaccine shot outside of trial as Britain began vaccinating its population.

Britain began rolling out the COVID-19 vaccine developed by Pfizer and BioNTech on Tuesday, the first Western country to start vaccinating its general population in what was hailed as a decisive watershed in defeating the coronavirus.

“I feel so privileged to be the first person vaccinated against Covid-19,” said Mrs. Keenan, as she received the jab from a nurse originally from the Philippines in front of a photographer and TV crew.

“It’s the best early birthday present I could wish for because it means I can finally look forward to spending time with my family and friends in the New Year after being on my own for most of the year.’’

Mrs. Keenan, known as Maggie to her friends, is a former jewelry shop assistant who only retired four years ago. She has a daughter, a son and four grandchildren.

Video footage shows her wearing a medical mask along with a blue t-shirt and cardigan while she receives the shot from nurse May Parsons.

Ms. Parsons, who has worked in Britain’s National Health Service for 24 years, said the last few months had been tough on everyone but it felt like there was now light at the end of the tunnel.

Britain is the worst-hit European country from COVID-19, with over 61,000 deaths, though Prime Minister Boris Johnson hopes to turn the tide against the disease by rolling out the Pfizer/BioNTech vaccine ahead of the United States or European Union.

The mass inoculation would fuel hope that the world may be turning a corner in the fight against a pandemic that has crushed economies and killed more than 1.5 million.

However, the ultra-cold storage and tricky logistics would limit its use for now.

British Health Secretary Matt Hancock and Stephen Powis, medical director for NHS England, said they both found it very emotional watching the vaccine programme roll out.

The BBC also carried an interview with another elderly lady who would receive the vaccine, very upset after she lost her husband from COVID-19 earlier.

Britain has ordered 40 million doses of the Pfizer/BioNTech shot. As each person requires two doses, that is enough to vaccinate 20 million people in the country of 67 million.

About 800,000 doses are expected to be available within the first week, with care home residents and carers, the over 80s and some health service workers the top priority to get them.