A pharmacist dilutes the Pfizer COVID-19 vaccine as it prepares to administer it to staff and residents at Goodwin House Bailey’s Crossroads, an older community in Falls Church, Virginia, on December 30, 2020.
Brendan Smialowski | AFP | Getty Images
The Covid-19 vaccine appears to cause severe allergic reactions at a significantly higher dose than other vaccines among the first wave of Americans to receive life-saving vaccines, the U.S. Centers for Disease Control and Prevention said Wednesday.
Although still rare, the CDC said there were 21 cases of anaphylaxis – a serious and life-threatening allergic reaction that rarely occurs after vaccination – out of the nearly 1.9 million people who took their first survey of Pfizer’s Covid-19. vaccine in mid to late December, according to a study published Wednesday in the CDC’s weekly report on morbidity and mortality.
This would mean that about 11 people out of every million vaccinated are likely to experience anaphylaxis, according to CDC data – about ten times higher than the flu vaccine.
Dr. Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases, told reporters during a conference call that the vaccinations were safe for public use and that the severe allergic reactions – although higher – were still considered rare.
“The anaphylaxis rate for Covid-19 vaccines may seem high compared to flu vaccines, but I want to assure you that it is still a rare outcome,” Messonnier said in the call before the study was released. She added that the data apply to both Pfizer and Moderna vaccines, which use similar mRNA technology.
Of the 21 people who experienced severe allergic reactions, 17 of them have a documented history of allergies or allergic reactions. Seven of the people had a history of anaphylaxis, the study found.
Most people experienced symptoms within 15 minutes of getting the chance, although anaphylaxis can occur hours after someone can be vaccinated, the CDC said. Among the 20 people with follow-up information available, all recovered or were discharged, the study found.
Most people experienced symptoms within 15 minutes of getting the chance, although anaphylaxis can occur hours after someone can be vaccinated, the CDC said. Among the 20 people with follow-up information available, all recovered or were discharged, the study found.
“Of course we would all hope that any vaccine would have no adverse events, but even at 11 cases per million doses administered, it is a very safe vaccine,” Messonnier said. She added that “tremendous efforts” are underway to determine exactly what is causing the severe allergic reactions.
According to the CNBC analysis of data compiled by Johns Hopkins University, the coronavirus kills an average of 2,670 people daily in the US, making the vaccine a ‘good value proposition’, Messonnier said.
According to the interim guidance of the CDC’s Advisory Committee on Immunization Practices, which was last updated in December, everyone should be monitored 15 minutes after their vaccination to ensure that they do not develop symptoms. People with a history of anaphylaxis should be watched for 30 minutes, the committee said.
The committee also suggested that people who develop anaphylaxis after their first dose should not receive a second dose, as both drugs require two shots for a week of each other for full effectiveness. The CDC’s study said that every vaccination site, such as epinephrine, should be ready to treat patients who may develop severe reactions.
“Fortunately, we know how to treat anaphylaxis, and we have made provision to ensure that people who administer the vaccine at immunization sites are ready to treat anaphylaxis,” Messonnier said.