Britain’s medicine regulator has advised that people with a history of significant allergic reactions do not get Pfizer-BioNTech’s Covid-19 vaccine after two people reported adverse effects on the first day of rollout.

National Health Service medical director Stephen Powis said the advice had been changed after two NHS workers reported anaphylactoid reactions associated with getting the shot.

“As is common with new vaccines the MHRA (regulator) have advised on a precautionary basis that people with a significant history of allergic reactions do not receive this vaccination, after two people with a history of significant allergic reactions responded adversely yesterday,” Powis said. “Both are recovering well,” he added.