Severe allergic reactions to vaccines are “one in a million” and NHS staff are trained to deal with them when they occur, the former head of immunisation at the Department of Health has said.
On Wednesday regulators warned that people with a history of significant allergies should not take the Pfizer/BioNTech Covid jab after two NHS workers had reactions.
But Professor David Salisbury, who was head of immunisation until 2013, moved to ease fears over dangers involved with the jab.
He said: “Severe adverse reactions, allergic ones to vaccines, do happen but they are very rare.
“They happen of the order of about one-in-a million doses. And everyone who administers vaccines in this country is trained to deal with them.”
He added that the two people who reacted, who carry epipens to deal with their allergies, have got a “different threshold for allergic reactions to many other people.”
Professor Salisbury said that clinical trials often screen out people with allergies, and so it is normal to “discover this sort of event in the surveillance that goes on after the programme rolls out.”
Asked if there could be a range of reactions as the vaccine is rolled out across the world, he said: “They will happen. What will also happen is there will be events after vaccination that actually have nothing to do with it.
“We need to be very careful to separate out coincidence from causality.”