On 4 May 2020 DELVE published Face Masks for the General Public, its first major report. The Royal Society’s news note summarises the finding.

The report draws on asymptomatic and pre-symptomatic transmission, droplet spread, and studies of homemade and surgical masks. It argues that widespread use where distancing is unpredictable could reduce onward transmission from wearers who do not yet know they are infectious — a source-control framing rather than protection of the wearer alone — and that cloth masks can contribute if used correctly.

Neil Lawrence was among DELVE’s leadership; Jessica Montgomery supported the initiative through the Royal Society secretariat. The report is part of the group’s DELVE body of work advising SAGE during 2020.