Authors:
Jonny Peter and 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
Affliations:
Jonny Peter
MBChB, FCP(SA), Cert. Allergy (SA), M.Med (Int Med)(UCT), PhD(Oxford)
Division of Allergology and Clinical Immunology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
Allergy and Immunology Unit, University of Cape Town Lung Institute, Cape Town, South Africa
Cascia Day
MBBCh, FCP(SA), M.Med (Int Med)(UCT), Dip HIV Man (SA).
Division of Allergology and Clinical Immunology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
Allergy and Immunology Unit, University of Cape Town Lung Institute, Cape Town, South Africa
Simba Takuva
MBChB, MSc, DTM&H, Dip HIV Man (SA).
Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
Azwidihwi Takalani
MBChB, MMed (CH), FCPHM (SA).
Department of Family Medicine and Primary Care, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
Imke Engelbrecht
MBChB (UP), HIV Management Dip. (SA)
Right to Care, South Africa
Nigel Garrett
MBBS, MRCP, MSc, PhD
CAPRISA, Centre for the AIDS Programme of Research in South Africa, Durban, South Africa
Department of Public Health Medicine, School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa
Ameena Goga
MBChB (UKZN), DTMH (Wits), DCH (College of Medicime of SA (CMSA)), MSc MCH (UCL),  FC(Paeds) (CMSA), MSc Epidemiology (Columbia university), PhD (UP), Cert Paeds Pulmo (CMSA), MPhil Paeds Pulmo (UP)
HIV Prevention Research Unit, South African Medical Research Council
Department of Paediatrics  and Child Health, University of Pretoria
Vernon Louw
MBChB, M.Med (Int Med)(Stell), PhD (HPE)(UFS)
Division of Clnical Haematology, Department of Medicine, Faculty of Health Sciences, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
Jessica Opie
MBChB Hons, MRCP (UK), FRCPA (Haem).
Division of Haematology, Department of Pathology, Faculty of Health Sciences, University of Cape Town
National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa
Barry Jacobson
MBChB (Pretoria), MMed (Haematology)(Wits), FRCS (Glasgow), PhD (Wits), FCPath (Haem) (SA)
Department of Haematology and Molecular Medicine
University of the Witwatersrand
The National Health Laboratory Service
Charlotte Maxeke Academic Hospital, Johannesburg, South Africa
Ian Sanne
MBBCh
Right to Care Johannesburg, South Africa
Linda Gail-Bekker
MBBCh, PhD
Desmond Tutu HIV Centre,
University of Cape Town Cape Town, South Africa
Glenda Gray
MBBCH, FCPaed(SA), DSc
Office of the President,
South African Medical Research Council
Franci Van Ziyl Drive, Parow valley, Cape Town, 7505
Key words : Ad26.COV2 S Vaccine, COVID19 vaccine, allergy, anaphylaxis
Word count: 2462
Corresponding author: Jonny Peter
Email: jonny.peter@uct.ac.za
Abstract ( n=241/250 words)
Background: The Janssen-Ad26.COV2.S vaccine is authorised for use in several countries with over 30 million doses administered. Mild and severe allergic adverse events following immunisation(AEFI) have been reported. The aim of this report is 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 477234 South African Healthcare Workers between 17 February and 17 May 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 (BCC) and NIAID case definitions.
Results: Only 251(0.052%) patients reported any allergic-type reaction(less than 1 in 2000), with four cases of adjudicated anaphylaxis (BCC level 1, n=3)(prevalence of 8.4 per million doses). All anaphylaxis cases had a prior history of drug or vaccine-associated anaphylaxis. Cutaneous allergic reactions were the commonest non-anaphylatic reactions and included: self-limiting, transient/localised rashes requiring no healthcare contact(n=92); or isolated urticaria and/or angioedema[n=70 median onset 48(IQR 11.5-120) hours post vaccination] that necessitated healthcare contact(81%), antihistamine(63%), and/or systemic/topical corticosteroid(16%). All immediate (including adjudicated anaphylaxis) and the majority of delayed AEFI(65/69) cases resolved completely.
Conclusions: Allergic AEFI are rare following a single-dose of Ad26.COV with complete resolution in all cases of anaphylaxis. Though 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, anaphylaxis, COVID19 adenovirus vaccine; Janssen-Ad26.COV2.S vaccine, urticaria