Footnotes

• Handling editor Anna Maria Geretti

• Twitter @saunders_j

• Contributors MK carried out the analysis and wrote the first draft. All other authors provided comments and edits. The original study design, data collection and data management were carried out by AH, DR, CVP, GH, CHM and JMS.

• Funding The original survey was funded by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Blood Borne and Sexually Transmitted Infections at University College London in partnership with UK Health Security Agency.

• Competing interests None declared.

• Provenance and peer review Not commissioned; internally peer reviewed.