Allergic reactions to the Ad26.COV2.S vaccine in South Africa

Jonny Peter; Cascia Day; Simbarashe Takuva; Azwidihwi Takalani; Imke Engelbrecht; Nigel Garrett; Ameena Goga; Vernon Louw; Jessica Opie; Barry Jacobson; Ian Sanne; Linda Gail-Bekker; Glenda Gray

doi:10.1016/j.jacig.2021.12.002

Allergic reactions to the Ad26.COV2.S vaccine in South Africa

J Allergy Clin Immunol Glob. 2021 Dec 9;1(1):2-8. doi: 10.1016/j.jacig.2021.12.002. eCollection 2022 Feb.

Authors

Jonny Peter^{1

2

3}, Cascia Day^{1

2

3}, Simbarashe Takuva^{4

5}, Azwidihwi Takalani^{4

6}, Imke Engelbrecht⁷, Nigel Garrett^{8

9}, Ameena Goga^{10

11}, Vernon Louw^{2

12}, Jessica Opie^{13

14}, Barry Jacobson^{14

15

16}, Ian Sanne⁷, Linda Gail-Bekker¹⁷, Glenda Gray¹⁸

Affiliations

¹ Division of Allergology and Clinical Immunology, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
² Groote Schuur Hospital, Cape Town, South Africa.
³ Allergy and Immunology Unit, University of Cape Town Lung Institute, Cape Town, South Africa.
⁴ Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Wash.
⁵ School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
⁶ Department of Family Medicine and Primary Care, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
⁷ Right to Care, Johannesburg, South Africa.
⁸ CAPRISA, Centre for the AIDS Programme of Research in South Africa, Durban, South Africa.
⁹ Department of Public Health Medicine, School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa.
¹⁰ HIV Prevention Research Unit, South African Medical Research Council, Cape Town, South Africa.
¹¹ Department of Paediatrics and Child Health, University of Pretoria, Pretoria, South Africa.
¹² Division of Clinical Haematology, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
¹³ Division of Haematology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
¹⁴ National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa.
¹⁵ the Department of Haematology and Molecular Medicine, University of the Witwatersrand, Johannesburg, South Africa.
¹⁶ Charlotte Maxeke Academic Hospital, Johannesburg, South Africa.
¹⁷ Desmond Tutu HIV Centre, University of Cape Town, Cape Town, South Africa.
¹⁸ South African Medical Research Council, Cape Town, South Africa.

Abstract

Background: The Janssen-Ad26.COV2.S vaccine is authorized for use in several countries, with more than 30 million doses administered. Mild and severe allergic adverse events following immunization (AEFI) have been reported.

Objective: We sought to detail allergic reactions reported during the Sisonke phase 3B study in South Africa.

Methods: A single dose of the Ad26.COV2.S vaccine was administered to 4,77,234 South African health care workers between February 17 and May 17, 2021. Monitoring of adverse events used a combination of passive reporting and active case finding. Telephonic contact was attempted for all adverse events reported as "allergy." Anaphylaxis adjudication was performed using the Brighton Collaboration and National Institute of Allergy and Infectious Disease case definitions.

Results: Only 251 (0.052%) patients reported any allergic-type reaction (<1 in 2000), with 4 cases of adjudicated anaphylaxis (Brighton Collaboration level 1, n = 3) (prevalence of 8.4 per million doses). All anaphylaxis cases had a previous history of drug or vaccine-associated anaphylaxis. Cutaneous allergic reactions were the commonest nonanaphylatic reactions and included self-limiting, transient/localized rashes requiring no health care contact (n = 92) or isolated urticaria and/or angioedema (n = 70; median onset, 48 [interquartile range, 11.5-120] hours postvaccination) that necessitated health care contact (81%), antihistamine (63%), and/or systemic/topical corticosteroid (16%). All immediate (including adjudicated anaphylaxis) and most delayed AEFI (65 of 69) cases resolved completely.

Conclusions: Allergic AEFI are rare following a single dose of Ad26.COV, with complete resolution in all cases of anaphylaxis. Although rare, isolated, delayed-onset urticaria and/or angioedema was the commonest allergic AEFI requiring treatment, with nearly half occurring in participants without known atopic disease.

Keywords: Allergic reaction; Janssen-Ad26.COV2.S vaccine; anaphylaxis; urticaria.