Of the first 1.9 million doses of Pfizer’s COVID-19 vaccine administered in the United States, there were 21 cases of severe allergic reactions to the vaccine, the Centers for Disease Control and Prevention reported on Jan. 6.
The rate of anaphylaxis seen so far – 11.1 cases per million vaccines – is higher than that of the flu vaccine, which is 1.3 cases per million doses, said Nancy Messonnier, director of the National Center for CDC Immunization and Respiratory Diseases. an informative report of 6 January. But reactions to COVID-19 vaccines are "still very rare," he said.
“They are safe and effective vaccines. We have good data to prove it, "Messonnier said. Vaccine side effects monitoring systems in the country are" incredibly robust, "he said, and" the only thing we've seen is these severe allergic reactions. "
Still, sites that administer COVID-19 vaccines need to be able to recognize signs of anaphylaxis, which, if it does occur, would most likely occur shortly after vaccination and be ready to treat, CDC officials said. And people who have a history of anaphylaxis as a result of any cause should be observed for 30 minutes after receiving the COVID-19 vaccine.
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Anaphylaxis, which can be life-threatening, requires emergency treatment with epinephrine. The UK, which began immunizing its population against COVID-19 with the Pfizer vaccine on December 8, was the first country to report cases of severe allergic reaction after vaccines (SN: 12/11/20).
The CDC reported 21 cases in the United States, covering vaccines administered Dec. 14-23, in a study of the morbidity and mortality report released online Jan. 6. These first vaccinations were only with the Pfizer vaccine. Officials still do not know what is causing the allergic reaction after immunization with the vaccine.
In the study there were no deaths from anaphylaxis. Nineteen of the 21 people were treated with epinephrine and four were hospitalized. Seven of the people in the report had experienced anaphylaxis in the past. CDC officials recommend that people with a history of anaphylaxis alert the person administering the shot before doing so.
The CDC continues to monitor these reactions. Since the report’s data was analyzed, the total number of reactions reported in the United States has grown slightly to 29 cases, the agency reported in the news report. Some of these new cases have been related to vaccination with the Modern COVID-19 vaccine.