Reporting of Allergic Reactions During Pfizer-BioNTech BNTT162B2 Vaccination in Israel.

BACKGROUND

In December 2020, the Israeli Ministry of Health launched a national vaccination campaign against SARS-CoV-2. Concomitant sporadic reports on anaphylactic responses in other countries raised safety concerns at the outset of this operation.

OBJECTIVE

To characterize reports on allergic reactions to coronavirus disease 2019 vaccines.

METHODS

Allergy events were reported by health care professionals throughout the country to Israeli Ministry of Health Division of Epidemiology via a Web-based computerized national vaccine registry. The study period was from December 19, 2020 to September 13, 2021, during which 14,475,979 injections were administered.

RESULTS

Allergic reactions were reported in 463 subjects, 99.3% of whom received Pfizer-BioNTech BNTT162B2. The reporting rate was 106 per million in December 2020. From January to May 2021, a reduction was observed to 66, 18, 14, eight, and zero per million, and reporting remained low until September. Mean age of subjects was 48.9 ± 16.7 years (range, 15-96 years) with a female preponderance of 78%. Epinephrine was administered in 34 subjects. Validated immediate allergy was observed in only 37 cases (8%), suggesting 2.5 to 3.3 bona fide reactions per million. In subjects with reactions classified as severe (n = 46), plausible allergy was identified in 36% to 41% of cases. A history of allergy was associated with high false reporting of immediate reactions (83%). Allergic events after the first dose did not compromise adherence to subsequent doses.

CONCLUSIONS

Excessive reporting of allergy declined over time and did not affect adherence to vaccination. The existence of previous allergy may affect reporting profiles, but not the occurrence of vaccine allergy.