UK Biobank SARS-CoV-2 Serology

The seroprevalence of SARS-CoV-2 infection was 6.6% at the start of the study period (end-May to June), increasing to 8.8% by the end of November/early December (Figure 1). [...] Figure 8b Map of percentage of individuals ever seropositive for SARS-CoV-2 infection by region of London 12 5. [...] New SARS-CoV-2 infections and duration of seroprevalence 6.1 New SARS-CoV-2 infections during the study period From end-May to early-December 2020, there were 453 new positive tests for SARS- CoV-2 antibodies, with most of these occurring from the start of September, corresponding to the start of the second wave. [...] 14 6.2 Duration of SARS-CoV-2 sero-positivity The duration of the presence of detectable antibodies was investigated among participants who were seropositive in the first month of the study and who had provided at least one subsequent sample and who had reported a date of symptom onset and/or had a PCR test result, in order to estimate an approximate date of infection (N=705). [...] Duration of sero-positivity was calculated as the time between the date of the onset of self-reported symptoms or a positive PCR test (whichever was first) until the date of the first negative test or the last available positive test.