Surveillance for Adverse Events After COVID-19 mRNA Vaccination

Abstract

IMPORTANCE Safety surveillance of vaccines against COVID-19 is critical to ensure safety, maintain trust, and inform policy.OBJECTIVES To monitor 23 serious outcomes weekly, using comprehensive health records on a diverse population. DESIGN, SETTING, AND PARTICIPANTSThis study represents an interim analysis of safety surveillance data from Vaccine Safety Datalink. The 10 162 227 vaccine-eligible members of 8 participating US health plans were monitored with administrative data updated weekly and supplemented with medical record review for selected outcomes from December 14, 2020, through June 26, 2021.EXPOSURES Receipt of BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) COVID-19 vaccination, with a risk interval of 21 days for individuals after vaccine dose 1 or 2 compared with an interval of 22 to 42 days for similar individuals after vaccine dose 1 or 2.MAIN OUTCOMES AND MEASURES Incidence of serious outcomes, including acute myocardial infarction, Bell palsy, cerebral venous sinus thrombosis, Guillain-Barré syndrome, myocarditis/pericarditis, pulmonary embolism, stroke, and thrombosis with thrombocytopenia syndrome. Incidence of events that occurred among vaccine recipients 1 to 21 days after either dose 1 or 2 of a messenger RNA (mRNA) vaccine was compared with that of vaccinated concurrent comparators who, on the same calendar day, had received their most recent dose 22 to 42 days earlier. Rate ratios (RRs) were estimated by Poisson regression, adjusted for age, sex, race and ethnicity, health plan, and calendar day. For a signal, a 1-sided P < .0048 was required to keep type I error below .05 during 2 years of weekly analyses. For 4 additional outcomes, including anaphylaxis, only descriptive analyses were conducted.RESULTS A total of 11 845 128 doses of mRNA vaccines (57% BNT162b2; 6 175 813 first doses and 5 669 315 second doses) were administered to 6.2 million individuals (mean age, 49 years; 54% female individuals). The incidence of events per 1 000 000 person-years during the risk vs comparison intervals for ischemic stroke was 1612 vs 1781 (RR, 0.97; 95% CI, 0.87-1.08); for appendicitis, 1179 vs 1345 (RR, 0.82; 95% CI, 0.73-0.93); and for acute myocardial infarction, 935 vs 1030 (RR, 1.02; 95% CI, 0.89-1.18). No vaccine-outcome association met the prespecified requirement for a signal. Incidence of confirmed anaphylaxis was 4.8 (95% CI, 3.2-6.9) per million doses of BNT162b2 and 5.1 (95% CI, 3.3-7.6) per million doses of mRNA-1273. CONCLUSIONS AND RELEVANCEIn interim analyses of surveillance of mRNA COVID-19 vaccines, incidence of selected serious outcomes was not significantly higher 1 to 21 days postvaccination compared with 22 to 42 days postvaccination. While CIs were wide for many outcomes, surveillance is ongoing.

Immune thrombocytopenia following immunisation with Vaxzevria ChadOx1-S (AstraZeneca) vaccine, Victoria, Australia

“…The observed rate of 0.8 per million doses for both vaccines in this cohort was not higher than expected background rate. This is in keeping with our analysis, which also did not demonstrate an increased rate of ITP following Pfizer-BioNTech vaccination, as well as other studies which have reported similar findings relating to mRNA COVID-19 vaccines [9] , [10] , [11] , [13] .…”

“…Emerging evidence suggests a causal link between ITP and COVID-19 vaccines, particularly AstraZeneca vaccine [9] , [10] . Other studies have investigated ITP following mRNA vaccines and to date found no association [11] , [12] , [13] . In our analysis, we examine a series of reported cases of ITP following vaccination with AstraZeneca and Pfizer-BioNTech vaccines and compare these to expected background rates in Victoria, Australia.…”

The way of SARS-CoV-2 vaccine development: success and challenges

“…However, an association between both mRNA vaccines and myocarditis/pericarditis was noticed in younger individuals aged 12–39 years, which requires further investigation (Fig. 4 ) 113 .

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Vaccines Against SARS-CoV-2 in Psoriasis Patients on Immunosuppressive Therapy: Implications of Vaccination Nationwide Campaign on Clinical Practice in Italy

“…Hypersensitivity reaction to vaccine components or anaphylactic reaction at the first administration are the only contraindications to vaccine administration. The latter is an exceptional reaction, and it can be treated with subcutaneous administration of adrenaline; no case of death due to anaphylaxis have been reported so far [9].…”