[1] South Limburg Publ Hlth Serv, Dept Sexual Hlth Infect Dis & Environm Hlth, NL-6160 HA Geleen, Netherlands
[2] Maastricht Univ, Med Ctr MUMC, Sch Publ Hlth & Primary Care CAPHRI, Dept Med Microbiol, NL-6202 AZ Maastricht, Netherlands
[3] Maastricht Univ, Dept Work & Social Psychol, NL-6200 MD Maastricht, Netherlands
[4] Maastricht Univ, Med Ctr MUMC, Dept Hlth Promot, Sch Publ Hlth & Primary Care CAPHRI, NL-6202 AZ Maastricht, Netherlands
[5] Univ Bradford, Fac Engn & Informat, Bradford BD7 1DP, W Yorkshire, England
[6] RIVM Natl Inst Publ Hlth & Environm, Ctr Infect Dis Control, NL-3720 BA Bilthoven, Netherlands
[7] STI AIDS Netherlands, NL-1016 GB Amsterdam, Netherlands
[8] Univ Amsterdam, Acad Med Ctr, Dept Gen Practice, NL-1105 AZ Amsterdam, Netherlands
[9] In Fact, Bradford BD17 7DB, W Yorkshire, England
[10] Univ Med Ctr Utrecht, Julius Ctr Hlth Sci & Primary Care, NL-3508 GA Utrecht, Netherlands