Britain administered the world’s first fully tested and approved COVID-19 vaccine to citizen Margaret Keenan on Tuesday. “I feel so privileged to be the first person vaccinated against COVID-19,” said Keenan, who turns 91 next week. “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.” Prime Minister Boris Johnson called the first injection “a shot in the arm for an entire nation” as British officials prepared to vaccinate 400,000 more people. American drug-maker Pfizer and Germany’s BioNTech developed the vaccine. Britain is first providing the vaccine to healthcare workers and people over age 80 in hospitals or under other immediate medical treatment. Last week, Britain became the first country to approve the vaccine for emergency use.