Since the UK became the first western country to license a vaccine against Covid a year ago, the world has embarked on a battle against the virus.
Here is a history of the vaccine.
November 2020.
A number of Covid vaccine candidates were being tested in large phase 3 clinical trials at this time. The University of Oxford/AstraZeneca was one of the jabs being considered. At the end of the month, analysis showed that it was 70.4% effective when combined with data from two dosing regimes. Sarah Gilbert, professor of vaccineology at the University of Oxford, said that the news took the world by surprise, and that it was another step closer to using vaccines to end the devastation caused by sars-coV-2.
The effectiveness of Pfizer and BioNTech jabs was announced this month. The efficacy portion of the trial showed the vaccine to prevent most of the cases of the disease.
December 2020.
The UK became the first western country to license a vaccine against Covid, with the first jab approved by Pfizer/BioNTech. It was initially given to the most at risk after being approved for emergency use.
The first person in the world to receive a vaccine was 90-year-old Margaret Keenan, who was inoculated at 6.31am on 8 December in Coventry.
The vaccine was initially given to patients who were already attending hospital as an outpatient or were about to be discharged home after a hospital stay, being the first in line.
January 2021.
The Oxford/AstraZeneca Covid-19 vaccine was approved for use in late December and the first person to receive it was Brian Pinker. The retired maintenance manager was at the hospital. The health secretary said it was a turning point in the fight against the virus.
The biggest vaccination programme in history is off to a strong start thanks to the hard work of the staff, according to the medical director.
The UK received 100m doses of the vaccine.
March 2021.
Several European countries stopped using the Oxford/AstraZeneca Covid vaccine because of fears it could cause serious blood clot. 17 million people have received the jab, and the blood clot incidents are much lower than would be expected in a general population, according to the company. Several countries resumed rolling out the vaccine after they found it was safe.
May 2021.
More than 60 million vaccine doses have been delivered by the UK. A study found that the Pfizer and AstraZeneca vaccines are highly effective after two doses against the variant identified in India.
Dr Jenny Harries said the study was the first real-world evidence of vaccine effectiveness against the variant, and that the forward message was for people to make sure they took up the offer of the second jab.
June 2021.
Half of all adults under the age of 30 in England received a first dose of the Covid vaccine this month, three weeks after the programme was opened to those in their 20s.
The minister of vaccines praised the achievement. He said it was great to see so many young people coming forward for their jabs.
The jabs were effective against the most severe outcomes, such as death, when the new Delta one emerged.
July 2021.
Double-vaccinated travellers from the US and most of Europe had their jab status recognised and could avoid being in England if they got there early. The loosened travel restrictions will allow millions more people to visit friends and family in the country, as well as boost the struggling tourism and aviation sectors.
October 2021.
Gordon Brown, the former prime minister of the UK, called on the UK and other G20 countries to arrange a military airlift of surplus Covid vaccines to poorer countries before they expire.
More than 160 former world leaders and global figures wrote a letter to richer countries asking them to send vaccines to countries that are struggling to immunize their populations.
November 2021.
Those working in care homes had to bevaccinated. Around 50,000 care home staff left their jobs.
The government extended who would get booster jabs during this month. The offer of a booster is extended to people aged 40 to 49, so Sajid Javid urged them to come forward.
The Omicron variant has caused the Covid booster vaccination scheme to be expanded.
