An Observational Cohort Study on the Incidence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection and B.1.1.7 Variant Infection in Healthcare Workers by Antibody and Vaccination Status. (3rd July 2021)

• Record Type: Journal Article
• Authors: Lumley, Sheila F; Rodger, Gillian; Constantinides, Bede; Sanderson, Nicholas; Chau, Kevin K; Street, Teresa L; O'Donnell, Denise; Howarth, Alison; Hatch, Stephanie B; Marsden, Brian D; Cox, Stuart; James, Tim; Warren, Fiona; Peck, Liam J; Ritter, Thomas G; de Toledo, Zoe; Warren, Laura; Axten, David; Cornall, Richard J; Jones, E Yvonne; Stuart, David I; Screaton, Gavin; Ebner, Daniel; Hoosdally, Sarah; Chand, Meera; Crook, Derrick W; O'Donnell, Anne-Marie; Conlon, Christopher P; Pouwels, Koen B; Walker, A Sarah; Peto, Tim E A; Hopkins, Susan; Walker, Timothy M; Stoesser, Nicole E; Matthews, Philippa C; Jeffery, Katie; Eyre, David W;
• Is Part Of: Clinical infectious diseases. Volume 74:Number 7(2022)
• Page Start: 1208
• Page End: 1219
• Publication Date: 2021-07-03
• Subjects: SARS-CoV-2 -- vaccine -- antibody -- healthcare worker -- immunity; Communicable diseases -- Periodicals; 616.905
• DOI: 10.1093/cid/ciab608
• Languages: English
• ISSNs: 1058-4838

Abstract

Abstract: Background: Natural and vaccine-induced immunity will play a key role in controlling the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. SARS-CoV-2 variants have the potential to evade natural and vaccine-induced immunity. Methods: In a longitudinal cohort study of healthcare workers (HCWs) in Oxfordshire, United Kingdom, we investigated the protection from symptomatic and asymptomatic polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infection conferred by vaccination (Pfizer-BioNTech BNT162b2, Oxford-AstraZeneca ChAdOx1 nCOV-19) and prior infection (determined using anti-spike antibody status), using Poisson regression adjusted for age, sex, temporal changes in incidence and role. We estimated protection conferred after 1 versus 2 vaccinations and from infections with the B.1.1.7 variant identified using whole genome sequencing. Results: In total, 13 109 HCWs participated; 8285 received the Pfizer-BioNTech vaccine (1407 two doses), and 2738 the Oxford-AstraZeneca vaccine (49 two doses). Compared to unvaccinated seronegative HCWs, natural immunity and 2 vaccination doses provided similar protection against symptomatic infection: no HCW vaccinated twice had symptomatic infection, and incidence was 98% lower in seropositive HCWs (adjusted incidence rate ratio 0.02 [95% confidence interval {CI} < .01–.18]). Two vaccine doses or seropositivity reduced the incidence of any PCR-positive result with or without symptoms by 90% (0.10 [95% CI .02–.38]) and 85% (0.15 [95% CI .08–.26]), respectively. Single-dose vaccination reduced the incidence of symptomatic infection by 67% (0.33 [95% CI .21–.52]) and any PCR-positive result by 64% (0.36 [95% CI .26–.50]). There was no evidence of differences in immunity induced by natural infection and vaccination for infections with S-gene target failure and B.1.1.7. Conclusions: Natural infection resulting in detectable anti-spike antibodies and 2 vaccine doses both provide robust protection against SARS-CoV-2 infection, including against the B.1.1.7 variant. Abstract : Natural infection resulting in detectable anti-spike antibodies and two vaccine doses both provided ≥85% protection against symptomatic and asymptomatic SARS-CoV-2 infection in healthcare workers, including against the B.1.1.7 variant. Single dose vaccination reduced symptomatic infection by 67%.