Pfizer-BioNTech COVID-19 (left) and Modern COVID-19 (right) vaccines.
Matic Zorman | Getty Images
The National Institutes of Health said on Wednesday it had begun looking into why some people had severe allergic reactions shortly after receiving Pfizer-BioNTech and Moderna Covid-19 vaccines.
“Public understanding has been concerned about reports of rare and severe allergic reactions to Moderna and Pfizer-BioNTech COVID-19 vaccines,” said Dr. Anthony Fauci, director of the NIH’s National Institute of Allergy and Infectious Diseases. , said in a statement.
“The information gathered during this study will help doctors advise people who are very allergic or who suffer from a mast cell disorder about the risks and benefits of receiving these two vaccines. However, for most people, the benefits of COVID-19 vaccination far outweigh the risks, “he said.
Medical experts say that allergic reactions to vaccines are rare, but can sometimes happen. Most rare and severe allergic reactions to vaccines have occurred in people with a history of allergies, public health officials said. An immediate allergic reaction usually occurs within 4 hours of vaccination and may include symptoms such as hives, swelling, and wheezing, according to the Centers for Disease Control and Prevention.
The NIH study will enroll 3,400 adults between the ages of 18 and 69 in up to 35 academic allergy research centers nationwide, the agency said. Participants will be divided into groups and randomly assigned to receive either the Pfizer-BioNTech vaccine, the Moderna vaccine, a placebo followed by the Pfizer-BioNTech vaccine, or a placebo followed by the Moderna vaccine.
Alkis Togias, head of NIAID’s Allergy, Asthma and Respiratory Biology Branch, told CNBC in December that U.S. agency researchers became interested in the rare phenomenon after reports that several people had reactions to the Pfizer vaccine, which he described as anaphylaxis. which can be life threatening.
The CDC asked health care providers to monitor patients for 15 minutes after vaccination and 30 minutes for those with a history of allergic reactions.
If someone has a severe allergic reaction after receiving the first dose of Covid-19 vaccine, the CDC recommends that they not receive the second dose of that vaccine, even if the allergic reaction was not severe enough to require emergency care.