FORT WAYNE, Ind. (WPTA21) -- Two British healthcare workers who got Pfizer's coronavirus vaccine developed severe reactions shortly after receiving their first doses.
Both of them have serious allergies, and carry adrenaline auto injectors like an EpiPen with them at all times.
It appears they needed to use the devices when they developed an anaphylactoid reaction after getting the shot.
While both are recovering well, their experience prompted British regulators to advise that people with a history of significant allergic reactions no' get the vaccine while investigators look into whether the shot or something else prompted the side effect.
Experts say this does not mean the vaccine is not safe for the general population.
"When we have vaccine trials, sometimes we don't find all of the side effects or the negative adverse reactions that might happen when it's released to the general population. So they fact that they are monitoring it, they're catching these things, that's a good sign," said IUPUI Communications Studies professor Katharine Head.
More than 42,000 people got the two doses in Pfizer's trial of its vaccine, and the FDA says in examining the trial's data there was the potential for slightly more adverse responses to the shots that were thought to be allergic reactions, rather than in the placebo group.
Those reactions amounted to about a half of one percent of the trial volunteers.