ADivision of Infectious Diseases, Department of Medicine, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.

BSaw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore, Singapore.

CInstitute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.

DDermatology Hospital, Southern Medical University, Guangzhou, China.

EGrindr for Equality, Grindr, Washington, DC, USA.

FClinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.