Neutralising antibodies to SARS coronavirus 2 in Scottish blood donors - a pilot study of the value of serology to determine population exposure

Craig Thompson; Nicholas Grayson; Robert Paton; José Lourenço; Bridget Penman; Lian Ni Lee; Valerie Odon; Juthathip Mongkolsapaya; Senthil Chinnakannan; Wanwisa Dejnirattisai; Matthew Edmans; Alexander Fyfe; Carol Imlach; Kreepa Kooblall; Nicholas Lim; Chang Liu; Cesar Lopez-Camacho; Carol-Anne McInally; Narayan Ramamurthy; Jeremy Ratcliff; Piyada Supasa; Beibei Wang; Alexander J Mentzer; Marc Turner; Calum Semple; John Kenneth Baillie; Heli Harvala; Gavin Screaton; Nigel Temperton; Paul Klenerman; Lisa Jarvis; Sunetra Gupta; Peter Simmonds

Sensitivity and specificity of the serological tests used. There are currently no agreed standards or controls available for serological testing for SARS-CoV-2. The results presented in the study are therefore based on a formally non-validated assay. However, we believe that 280 the neutralisation antibody test is likely to be robust. Firstly, it is based on the same design as pMN assays for SARS-CoV-1, ebolavirus and influenza A virus; pMN assays that have demonstrated high specificity for target virus neutralising antibodies and a sensitivity that is often greater than achieved in neutralising antibody assays for whole virus [13] [14] [15] . Overall, although sampling was limited, there was concordance between the pMN assay to detect 285 neutralising antibody and the detection of anti-spike IgG antibody by ELISA . The pMN assay does, however, require comparison with neutralisation of live virus for further interpretation of these data.