A day after the UK began administering coronavirus vaccines, health officials are telling those with severe allergies not to get the injection.
On Wednesday, British authorities said people with a "significant history of allergic reactions" should not be given the Pfizer/BioNTech COVID-19 vaccine after two health care workers experienced symptoms a day after receiving the shot.
The two staff members — who both carried an adrenaline auto injector and had a history of allergic reactions — developed symptoms of an anaphylactoid reaction.
"As is common with new vaccines, the MHRA [Medicines and Healthcare products Regulatory Agency] 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," Stephen Powis, the national medical director for National Health Service England, said in a statement.
Powis added that the two employees are “[both] recovering well.”
The MHRA added that vaccines "should only be carried out in facilities where resuscitation measures are available."
"We are fully investigating the two reports that have been reported to us as a matter of priority," an MHRA spokesperson said. “Once all the information has been reviewed we will communicate updated advice.”
After receiving word of "two yellow card reports that may be associated with allergic reaction," Pfizer said in their own statement, "As a precautionary measure, the MHRA has issued temporary guidance to the NHS while it conducts an investigation in order to fully understand each case and its causes. Pfizer and BioNTech are supporting the MHRA in the investigation.”
On Tuesday, the US Food and Drug Administration (FDA) said the Pfizer/BioNTech trial data revealed that there were potentially slightly more adverse responses thought to be allergic reactions among the vaccine group compared with the placebo group, at 0.63% compared with 0.51%.
Vaccine expert Dr. Paul Offit told CNN on Wednesday that allergic reactions to vaccines are not uncommon.
"Certainly, vaccines can cause severe allergic reactions. In the United States, roughly one of every 1.4 million doses of vaccines is complicated by a severe allergic reaction,” Offit said.
Rather than provide a "blanket recommendation" for people with allergies, Offit says "the smarter thing to do would be to try and look at these two patients and see what specific component of the vaccine they were allergic to."
On Tuesday, British grandmother Margaret Keenan, 90, became the first person in the world to receive the vaccine at the University Hospital Coventry in England.
NHS England told CNN on Wednesday that thousands of British citizens were vaccinated that same day.
Pfizer previously announced last month that its vaccine was proven to be at least 95 percent effective with "no serious safety concerns observed."