The Prime Minister had previously dismissed concerns it was linked to blood clots, and told the nation it was “safe” at a press briefing on Thursday.
His jab comes as new figures suggest half of adults in England are likely to have received their first dose of Covid-19 vaccine – making it the first of the four UK nations to pass this symbolic milestone.
A total of 22,337,590 people had been given a first jab as of March 18, according to NHS England.
This is the equivalent of 50.5% of the population of England aged 18 and over, based on the latest estimates by the Office for National Statistics (ONS).
Meanwhile countries including France, Germany and Italy began restarting their vaccine programmes with the AstraZeneca jab – reversing earlier decisions to suspend them over blood clot concerns.
The European Medicines Agency (EMA) said the AstraZeneca vaccine was “safe and effective” and its benefits in preventing Covid-19 hospital admission and death greatly outweighed potential risks.
The EMA has, however, been unable to say definitively that the jab is not linked to “extremely rare” blood clots on the brain, of which there have been 18 reports among millions of people vaccinated.
The World Health Organisation (WHO) and the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) have said that the jab is safe and have encouraged people to take up their vaccine appointments.
The WHO’s advisory committee on vaccine safety issued a formal statement on Friday saying the vaccine “continues to have a positive benefit-risk profile, with tremendous potential to prevent infections and reduce deaths across the world”.
New ONS figures show that around one in 340 people in private households in England had Covid-19 in the week to March 13, down from around one in 270 the week before.
In Wales, around one in 430 people are estimated to have had Covid-19 in the week to March 13 (down from one in 365), while the figure was one in 315 in Northern Ireland (similar to the week before) and around one in 275 in Scotland, up from one in 320. The current reproduction rate (R) for the UK is 0.6 to 0.9.
Other data shows the UK ended 2020 with one of the highest levels of excess mortality for people aged under 65 among countries in Europe.