Detection of neutralising antibodies to SARS coronavirus 2 to determine population exposure in Scottish blood donors between March and May 2020
Authors:
Thompson C, Grayson N, Paton R, Bolton J, Lourenco J, Penman B, Lee L, Odon V, Mongkolsapaya J, Chinnakannan S, Dejnirattisai W, Edmans M, Fyfe A, Imlach C, Kooblall K, Lim N, Liu C, Lopez-Camacho C, McInally C, McNaughton A, Ramamurthy N, Ratcliff J, Supasa P, Sampson O, Wang B, Mentzer A, Turner M, Semple M, Baillie J, Harvala H, Screaton G, Temperton N, Klenerman P, Jarvis L, Gupta S, Simmonds P,
Abstract:
Background
The progression and geographical distribution of SARS coronavirus 2 (SARS-CoV-2) infection in the UK and elsewhere is unknown because typically only symptomatic individuals are diagnosed. We performed a serological study of blood donors in Scotland between the 17 th of March and the 18 th of May to detect neutralising antibodies to SARS-CoV-2 as a marker of past infection and epidemic progression.
Aim
To determine if sera from blood bank donors can be used to track the emergence and progression of the SARS-CoV-2 epidemic.
Methods
A pseudotyped SARS-CoV-2 virus microneutralisation assay was used to detect neutralising antibodies to SARS-CoV-2. The study group comprised samples from 3,500 blood donors collected in Scotland between the 17 th of March and 19 th of May, 2020. Controls were collected from 100 donors in Scotland during 2019.
Results
All samples collected on the 17 th March, 2020 (n=500) were negative in the pseudotyped SARS-CoV-2 virus microneutralisation assay. Neutralising antibodies were detected in 6/500 donors from the 23 th -26 th of March. The number of samples containing neutralising antibodies did not significantly rise after the 5 th -6 th April until the end of the study on the 18 th of May. We find that infections are concentrated in certain postcodes indicating that outbreaks of infection are extremely localised. In contrast, other areas remain comparatively untouched by the epidemic.
Conclusion
These data indicate that sero-surveys of blood banks can serve as a useful tool for tracking the emergence and progression of an epidemic like the current SARS-CoV-2 outbreak.