Analysis of SARS-CoV-2 antibody seroprevalence in Northern Ireland during 2020–2021
Michelle K. Greene,
Peter Smyth,
Andrew English,
Joseph McLaughlin,
Magda Bucholc,
Janice Bailie,
Julie McCarroll,
Margaret McDonnell,
Alison Watt,
George Barnes,
Mark Lynch,
Kevan Duffin,
Gerard Duffy,
Claire Lewis,
Jacqueline A. James,
Alan W. Stitt,
Tom Ford,
Maurice O'Kane,
Taranjit Singh Rai,
Anthony J. Bjourson,
Christopher Cardwell,
J Stuart Elborn,
David S. Gibson,
Christopher J. Scott
Affiliations
Michelle K. Greene
The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, UK
Peter Smyth
The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, UK
Andrew English
Personalised Medicine Centre, School of Medicine, Ulster University, Londonderry, UK; School of Health and Life Sciences, Teeside University, Middlesbrough, UK
Joseph McLaughlin
Personalised Medicine Centre, School of Medicine, Ulster University, Londonderry, UK
Magda Bucholc
Intelligent Systems Research Centre, School of Computing, Engineering & Intelligent Systems, Ulster University, Londonderry, UK
Janice Bailie
HSC R&D Division, Public Health Agency, Belfast, UK
Julie McCarroll
HSC R&D Division, Public Health Agency, Belfast, UK
Margaret McDonnell
Department of Clinical Biochemistry, Belfast Health and Social Care Trust, Belfast, UK
Alison Watt
Regional Virology Laboratory, Belfast Health and Social Care Trust, Belfast, UK
George Barnes
Department of Clinical Biochemistry, South Eastern Health and Social Care Trust, Dundonald, UK
Mark Lynch
Department of Clinical Biochemistry, Altnagelvin Hospital, Western Health and Social Care Trust, Londonderry, UK
Kevan Duffin
Department of Clinical Biochemistry, Southern Health and Social Care Trust, Portadown, UK
Gerard Duffy
Department of Clinical Biochemistry, Northern Health and Social Care Trust, Antrim, UK
Claire Lewis
The Northern Ireland Biobank, Queen's University Belfast, Belfast, UK
Jacqueline A. James
The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, UK; The Northern Ireland Biobank, Queen's University Belfast, Belfast, UK; Regional Molecular Diagnostic Service, Belfast Health and Social Care Trust, Belfast, UK
Alan W. Stitt
Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, UK
Tom Ford
Bacteriology Branch, Veterinary Sciences Division, AFBI, Belfast, UK
Maurice O'Kane
Department of Clinical Biochemistry, Altnagelvin Hospital, Western Health and Social Care Trust, Londonderry, UK
Taranjit Singh Rai
Personalised Medicine Centre, School of Medicine, Ulster University, Londonderry, UK
Anthony J. Bjourson
Personalised Medicine Centre, School of Medicine, Ulster University, Londonderry, UK
Christopher Cardwell
Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
J Stuart Elborn
Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, UK
David S. Gibson
Personalised Medicine Centre, School of Medicine, Ulster University, Londonderry, UK
Christopher J. Scott
The Patrick G Johnston Centre for Cancer Research, Queen's University Belfast, Belfast, UK; Corresponding author. School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7AE, UK.
Background: With the spread of SARS-CoV-2 impacting upon public health directly and socioeconomically, further information was required to inform policy decisions designed to limit virus spread during the pandemic. This study sought to contribute to serosurveillance work within Northern Ireland to track SARS-CoV-2 progression and guide health strategy. Methods: Sera/plasma samples from clinical biochemistry laboratories were analysed for anti-SARS-CoV-2 antibodies. Samples were assessed using an Elecsys anti-SARS-CoV-2 or anti-SARS-CoV-2 S ECLIA (Roche) on an automated cobas e 801 analyser. Samples were also assessed via an anti-SARS-CoV-2 ELISA (Euroimmun). A subset of samples assessed via the Elecsys anti-SARS-CoV-2 ECLIA were subsequently analysed in an ACE2 pseudoneutralisation assay using a V-PLEX SARS-CoV-2 Panel 7 for IgG and ACE2 (Meso Scale Diagnostics). Results: Across three testing rounds (June–July 2020, November–December 2020 and June–July 2021 (rounds 1–3 respectively)), 4844 residual sera/plasma specimens were assayed for anti-SARS-CoV-2 antibodies. Seropositivity rates increased across the study, peaking at 11.6 % (95 % CI 10.4 %–13.0 %) during round 3. Varying trends in SARS-CoV-2 seropositivity were noted based on demographic factors. For instance, highest rates of seropositivity shifted from older to younger demographics across the study period. In round 3, Alpha (B.1.1.7) variant neutralising antibodies were most frequently detected across age groups, with median concentration of anti-spike protein antibodies elevated in 50–69 year olds and anti-S1 RBD antibodies elevated in 70+ year olds, relative to other age groups. Conclusions: With seropositivity rates of <15 % across the assessment period, it can be concluded that the significant proportion of the Northern Ireland population had not yet naturally contracted the virus by mid-2021.
