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

The representativeness of the study region. The study was based upon testing anonymised samples from blood donors collected in March, 2020. Scotland has a population of 5.4 million and a relatively low population density (67.2/km 2 ). However, it contains several large cities (Glasgow, Edinburgh) which geospatially would support transmission networks typical 245 of much of Western Europe. Public health data for COVID-19 cases indicated that by the 26 th March, shortly after donor collection, a total of 894 infections had been diagnosed and 25 deaths recorded (normalised incidence: 0.46/100,000). This compares to an overall confirmed incidence for the UK of 0.62/100,000 on the same day. The rate in Scotland was higher than Germany (0.18/100,000), comparable to Denmark (0.41/100,000), France (0.30/100,000) and 250