With input from Dr Monica Vasudev

1346: Anaphylaxis

1. 21 cases of anaphylaxis out of 1.8 M doses of Pfizer-BioNTech vaccine – approximately 1 in 87,000 injections). Although this is rare, but it is higher than the risk with other vaccines which is 1.3 per million.
2. Majority of anaphylaxis cases have been reported within 30 minutes of receiving the jab.
3. Of 21 cases, 5 were allergic to some food; three of these also had a history of drug allergy. Twelve had had allergic reactions to medications or vaccines previously, and one had environmental allergies.
4. Moderna vaccine - some cases of delayed facial swelling have been reported without serious consequences.
5. Vaccine allergy is a rare occurrence. The cause behind such rare allergic reactions is often an excipient. Meat proteins such as gelatin and, alpha-gal (rare) have also been reported to be the causes of IgE-mediated reactions in vaccines that have higher gelatin content (like MMR and VZV). In certain cases, atopy (especially food allergy) may act as a risk factor for vaccine reactions. The influenza vaccine cultured in eggs contains very little egg allergen and is not a concern even for those patients who have severe egg allergy.
6. Skin prick and intradermal testing to PEG-3350 has been reported and was found to be positive in some patients with a history of anaphylaxis to this product. The skin test demonstrated a mild urticarial rash with dyspnea and diffuse pruritus.
7. CDC: Individuals with anaphylactic reaction to the first dose of the COVID-19 vaccine should not be given the second dose. In case of doubt, such as when there is a possible vasovagal reaction after vaccination, assessing serum tryptase (or SC5b-9, the terminal complement complex) may confirm the diagnosis of anaphylaxis.
8. The Johnson & Johnson COVID-19 vaccine uses an adenovirus vector rather than mRNA. For patients who may have had anaphylaxis after the first dose but the reaction is in doubt, a scratch test with sequential challenge could be performed.  (Source: Medscape)

1347: Autoantibodies

1. The COVID-19 virus seems to prompt the body to develop armament to attack its own tissues. The finding could clarify why symptoms persist in some people for months, a phenomenon which has been termed as long COVID. It could also help explain the development of a serious inflammatory syndrome, called MIS-C or MIS-A, in some children and adults.
2. A study included data from over 300 patients from two hospitals in California, one in Pennsylvania, and another in Germany.
3. Autoantibodies were more common after COVID, with 50% of the patients hospitalized having autoantibodies, compared to less than 15% of those who were healthy and uninfected.
4. Some people who had autoantibodies were found to have little change as their infections progressed. This could mean that the autoantibodies were there since the beginning. In others, nearly 20% of people who had them, the autoantibodies became more common as the infection progressed. This indicates that they were directly related to the viral infection.
5. Some of these were antibodies known to attack interferon. Interferons impact a viruss ability to copy itself. Some individuals in the study were found to have autoantibodies against muscles and connective tissues. (Source: WebMD)

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA