Do Antibody Positive Healthcare Workers Have Lower SARS-CoV-2 Infection Rates than Antibody Negative Healthcare Workers? Large Multi-Centre Prospective Cohort Study (The SIREN Study), England: June to November 2020

• DOI: 10.2139/ssrn.3768524
• Publication Date: 2021-02-04T23:42:26Z
• Authors: Victoria Jane Hall; Sarah Foulkes; Andre Charlett; Ana Atti; Edward JM Monk; Ruth Simmons; Edgar Wellington; Michelle Cole; Ayoub Saei; Blanche Oguti; Katie Munro; S. Wallace; Peter D. Kirwan; Madhumita Shrotri; Amoolya Vusirikala; Sakib Rokadiya; Meaghan Kall; Maria Zambon; Mary E. Ramsay; T. Brooks; SIREN Study Group; Colin Brown; Meera A. Chand; Susan Hopkins
• Keywords: 03 medical and health sciences; 0302 clinical medicine; 16. Peace & justice; 3. Good health

Background: There is an urgent need to better understand whether individuals who have recovered from COVID-19 are protected future SARS-CoV-2 infection.Methods: A large multi-centre prospective cohort was recruited publicly funded hospital staff in the UK. Participants attended regular PCR and antibody testing (every 2-4 weeks) completed fortnightly questionnaires on symptoms exposures. At enrolment, participants were assigned either positive (antibody or prior PCR/antibody test positive) negative negative, not previously known be positive). Potential reinfections clinically reviewed classified according case definitions (confirmed, probable, possible (subdivided by symptom-status)) depending hierarchy of evidence. Individuals primary infection excluded this analysis if confirmed only. Reinfection rates compared against new positives using a mixed effective multivariable logistic regression analysis.Findings: Between 18 June 09 November 2020, 44 (2 42 possible) detected baseline 6,614 participants, collectively contributing 1,339,078 days follow-up. This compares with 318 infections 94 seroconversions 14,173 1,868,646 The incidence density per 100,000 person between 2020 3.2 cohort, 22.4 cohort. adjusted odds ratio 0.17 for all (95% CI 0.13-0.24) infections. median interval reinfection over 160 days.Interpretation: history associated 83% lower risk infection, protective effect observed five months following infection. minimum likely as included.Trial Registration: Trial registered ISRCTN, ID: ISRCTN11041050. https://www.isrctn.com/ISRCTN11041050.Funding Statement: Department Health Social Care Public England, contributions Scottish, Welsh Northern Irish governments.Declaration Interests: No conflicts interest declared.Ethics Approval IRAS ID 284460, Berkshire Research Ethics Committee, Authority Wales approval granted 22 May 2020.