CDC: anaphylaxis with COVID Vax 10 times greater than for flu shots

Although rare, the anaphylactic dose to COVID-19 mRNA vaccines has appeared about ten times as documented for flu shots, CDC officials said Wednesday.

Overall, 21 cases of anaphylaxis after COVID vaccination were reported from approximately 1.9 million doses given on December 23, according to an early Weekly report on diseases and deaths release. That amounts to 11.1 cases per million versus an estimated 1.3 cases per million due to inactivated flu vaccine, officials said in a call to the media.

They noted that there are currently 29 confirmed cases of anaphylaxis reported with the Pfizer / BioNTech and Moderna vaccines. In addition, officials said that the MMWR report of 14-23 December focuses on the Pfizer vaccine, as the Moderna vaccine was only available on 21 December. However, there are not enough data to see a difference in risk between vaccines.

No deaths due to anaphylaxis have been seen so far.

Nancy Messonnier, managing director of CDC’s National Center for Immunization and Respiratory Diseases, stressed that these events are rare and that the benefits of the COVID-19 vaccine outweigh the risks. Furthermore, it compares with the numbers for flu ‘the point’ when there are more than 2000 deaths daily due to COVID-19 in the USA

“It’s still a good value proposition,” she said. “Even though the rate is higher than we see after routine vaccinations, anaphylaxis still remains rare.”

Of the 21 cases reviewed in 2005 MMWR, 18 have documented allergies or allergic reactions to drugs, medicinal products, food or insect stings, and seven have experienced anaphylaxis in the past, including one to a rabies vaccine and one to a flu vaccine (H1N1).

Messonnier acknowledges the millions of people who have allergies to food or insect stings, and highlights the difference between ‘someone who had a mild allergic reaction next week versus someone with a severe allergic reaction next week’.

“A lot of people have a history of allergies to bee stings or food, and the fact that people in this group have had anaphylaxis … may not mean that allergic reactions have a higher risk, but it does,” she added.

Messonnier noted that CDC guidance suggests that anyone with a history of anaphylaxis should speak to their healthcare provider for vaccination for whatever reason and that clinicians should exercise their judgment.

CDC officials said anyone with a history of anaphylaxis who gets the vaccine should watch for 30 minutes afterward, because people who have had anaphylaxis before are at risk of getting it again.

The agency recently updated its interim guidance to clinicians on contraindications to the vaccine, adding that those with an immediate allergic reaction to the first vaccine should not receive a second dose.

Seventeen of the 21 cases were among those with a history of anaphylaxis, and the mean time from vaccination to onset of symptoms was 13 minutes, although approximately 70% of the patients had symptoms within 15 minutes. The mean age of patients was 40 and 19 women.

The MMWR report noted that female dominance was seen earlier for immediate hypersensitivity reactions to influenza vaccine (H1N1). But the disproportion with COVID vaccination may simply be due to more women than men receiving the Pfizer / BioNTech vaccine, the authors said.

Nineteen patients were treated with epinephrine, 17 were treated in the emergency department and four were admitted to the hospital, including three in intensive care. Among 20 people with available information, all were discharged home.

Messonnier also briefly addressed reports of health workers preferring not to be vaccinated, saying she was “definitely concerned” about it.

“This makes it extremely important that we get the correct information to health workers and that we get rid of incorrect information quickly,” she said. “We need them not only to protect themselves, but to educate their patients so that everyone understands these vaccines … have a good safety profile, they work, and they … can help us overcome this pandemic. to end. “