Around one in one hundred thousand people may suffer from severe allergic reactions to Pfizer’s coronavirus vaccine, US health officials said on Wednesday.
The officials further stressed that the benefits of immunisation significantly outweigh Covid-19 risk, Medical Xpress reported.
Allergic reactions to Covid-19 vaccines are about 1.3 per 1 million people: Study
The data comes from the Centers for Disease Control and Prevention (CDC). The agency has documented 21 cases of anaphylaxis after administration of a reported 1,893,360 shots from December 14 to December 23.
Allergic reactions to Pfizer’s coronavirus vaccine more frequent than expected: US official
“This averages out to a rate of 11.1 anaphylaxis cases per one million doses administered,” senior CDC official Nancy Messonnier told reporters.
In comparison, flu vaccines cause around 1.3 anaphylaxis cases per million doses inoculated. Hence, the rate of allergic reactions to Pfizer is 10 times greater.
Provisions in place
Messonnier noted that anaphylaxis cases were still “exceedingly rare.” She added: “A good value proposition for someone to get vaccinated is their risk from Covid and poor outcomes from Covid is still more than the risk of a severe outcome from the vaccine.”
“Fortunately, we know how to treat anaphylaxis, and we’ve put provisions in place to ensure that at immunisation sites, the folks administering the vaccine are ready to treat anaphylaxis,” she said.
According to the CDC study, the 21 cases ranged in age from 27 to 60 years old, with a median age of 40, and all but two were treated with epinephrine.
Nineteen of the cases (90 per cent) occurred in females, and the median onset time of symptoms was 13 minutes, but ranged from two to 150 minutes, it revealed.
Four (19 per cent) of patients were hospitalised, including three in intensive care, and 17 (81 per cent) were treated in an emergency department. All but one was known to have been discharged home or recovered at the time of the study, and there were no deaths.
Allergic symptoms included rash, a sensation of throat closure, swollen tongue, hives, difficulty breathing, hoarseness, swollen lips, nausea, and persistent dry cough.