COVID-19 Vaccines and Allergic reactions

Boston health care worker who experienced reaction to Moderna coronavirus vaccine has a history of allergies.

FREMONT, CA: A health care worker who experienced an allergic reaction after receiving a Moderna Covid-19 vaccine at Boston Medical Center on Christmas Eve tells CNN he has a history of allergies.

This is the first known case of allergic reaction from a Moderna coronavirus vaccine, although there have been at least six similar reported cases in the United States associated with the Pfizer/BioNTech vaccine.

The employee received the Moderna vaccine Thursday and was observed post vaccination by trained nurses. He felt he was developing an allergic reaction and was allowed to self-administer his personal epi-pen. He was taken to the Emergency Department, evaluated, treated, observed and discharged.

Ray Jordan, a spokesperson from the biotechnology company, told CNN: "Moderna can't confirm the incident but reported the potential adverse event through its internal safety reporting system and Moderna is further investigating the incident."

It's still unknown what ingredient in the coronavirus vaccines may be causing severe allergic reactions in some people. Dr. Peter Marks, who heads the FDA's Center for Biologics Evaluation and Research, said in a briefing last week that the agency is investigating a compound known as polyethylene glycol (PEG), as well as four other possible ingredients in the formulation.

Pfizer CEO Albert Bourla explained in a town hall that adverse reactions to the vaccine were "very rare" in clinical trials. He pointed out that now that the vaccine is being distributed to millions of people, adverse events are inevitable. He added that these incidents should not keep people from taking the vaccine, especially those with preexisting conditions that put them at risk for severe Covid-19.  Moncef Slaoui, chief scientific adviser for Operation Warp Speed, said there are discussions between the vaccine makers and the National Institutes of Health to consider conducting clinical trials of Covid-19 vaccines in very allergic populations, such as those who have to carry an EpiPen with them at all times. He said a trial could help understand the rate of allergic reactions and what is provoking them.