SARS-CoV-2 antibodies and breakthrough infections in the Virus Watch cohort

• Published in: Nature communications 2022-08, Vol.13 (1), p.4869-8, Article 4869
• Main Authors: Aldridge, Robert W., Yavlinsky, Alexei, Nguyen, Vincent, Eyre, Max T., Shrotri, Madhumita, Navaratnam, Annalan M. D., Beale, Sarah, Braithwaite, Isobel, Byrne, Thomas, Kovar, Jana, Fragaszy, Ellen, Fong, Wing Lam Erica, Geismar, Cyril, Patel, Parth, Rodger, Alison, Johnson, Anne M., Hayward, Andrew
• Format: Article
• Language: English
• Subjects: 101/1; 13/1; 631/326/590; 631/326/596/4130; 692/308/174; 692/308/409; Antibodies; Antibodies, Viral; BNT162 Vaccine; Confidence intervals; COVID-19 - prevention & control; COVID-19 Vaccines; Estimation; Health risks; Humanities and Social Sciences; Humans; Immunization; Infections; multidisciplinary; Risk management; Risk reduction; SARS-CoV-2; Science; Science (multidisciplinary); Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Vaccine efficacy; Vaccines; Viral diseases; Viral Vaccines; Viruses
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-32265-5

A range of studies globally demonstrate that the effectiveness of SARS-CoV-2 vaccines wane over time, but the total effect of anti-S antibody levels on risk of SARS-CoV-2 infection and whether this varies by vaccine type is not well understood. Here we show that anti-S levels peak three to four weeks following the second dose of vaccine and the geometric mean of the samples is nine fold higher for BNT162b2 than ChAdOx1. Increasing anti-S levels are associated with a reduced risk of SARS-CoV-2 infection (Hazard Ratio 0.85; 95%CIs: 0.79-0.92). We do not find evidence that this antibody relationship with risk of infection varies by second dose vaccine type (BNT162b2 vs. ChAdOx1). In keeping with our anti-S antibody data, we find that people vaccinated with ChAdOx1 had 1.64 times the odds (95% confidence interval 1.45-1.85) of a breakthrough infection compared to BNT162b2. We anticipate our findings to be useful in the estimation of the protective effect of anti-S levels on risk of infection due to Delta. Our findings provide evidence about the relationship between antibody levels and protection for different vaccines and will support decisions on optimising the timing of booster vaccinations and identifying individuals who should be prioritised for booster vaccination, including those who are older, clinically extremely vulnerable, or received ChAdOx1 as their primary course. Our finding that risk of infection by anti-S level does not interact with vaccine type, but that individuals vaccinated with ChAdOx1 were at higher risk of infection, provides additional support for the use of using anti-S levels for estimating vaccine efficacy. Here the authors provide data from a sub-cohort of the Virus Watch study (19,556 adults) who completed at-home capillary blood sampling on a monthly basis and describe an association between anti-spike antibody levels and risk of SARS-CoV-2 infection.