Epidemiological impacts of the NHS COVID-19 app in England and Wales throughout its first year.

Kendall M., Tsallis D., Wymant C., Di Francia A., Balogun Y., Didelot X., Ferretti L., Fraser C.

The NHS COVID-19 app was launched in England and Wales in September 2020, with a Bluetooth-based contact tracing functionality designed to reduce transmission of SARS-CoV-2. We show that user engagement and the app's epidemiological impacts varied according to changing social and epidemic characteristics throughout the app's first year. We describe the interaction and complementarity of manual and digital contact tracing approaches. Results of our statistical analyses of anonymised, aggregated app data include that app users who were recently notified were more likely to test positive than app users who were not recently notified, by a factor that varied considerably over time. We estimate that the app's contact tracing function alone averted about 1 million cases (sensitivity analysis 450,000-1,400,000) during its first year, corresponding to 44,000 hospital cases (SA 20,000-60,000) and 9,600 deaths (SA 4600-13,000).

DOI

10.1038/s41467-023-36495-z

Type

Journal article

Journal

Nat Commun

Publication Date

22/02/2023

Volume

14

Keywords

Humans, COVID-19, Mobile Applications, SARS-CoV-2, State Medicine, Wales, Contact Tracing, England

Permalink Original publication