Objective: The objective of this study was to explore risk behavior and routes of transmission in men having sex with men (MSM) with newly diagnosed sexually transmitted infections (STIs).
Methods: A questionnaire on clinical diagnosis and manifestation site for acute STIs was completed by physicians participating in a sentinel study. Patients contributed information on sexual risk behavior and the likely route of STI transmission.
Results: Three hundred fifty-six diagnosis forms and 169 matching patient questionnaires could be analyzed. The most frequent diagnosis was syphilis (n = 147; 33% primary syphilis with ulcer localization 71% genital, 22% anorectal, and 8% oral; 67% secondary syphilis), followed by gonorrhea (n = 136; 59% genital, 34% rectal, 7% pharyngeal) and Chlamydia trachomatis infection (n = 51; 48% genital, 48% rectal, 4% pharyngeal). In 12 patients, more than one infection was diagnosed, and 2 or 3 sites were affected in 11 patients. Approximately 60% of infections were acquired by genital–oral and oral–anal practices. Unprotected anal intercourse (UAI) was reported more often by HIV-positive men (mostly receptive) and men with high partner numbers.
Conclusion: High partner numbers, an important role of genital–oral sexual practices for the transmission of STIs, and relatively high frequencies of mostly receptive UAI in HIV-positive men are all contributing to increasing STI incidences among MSM.
Data on sexual risk behavior and routes of sexually transmitted infection transmission in men who have sex with men were collected in the German sexually transmitted disease sentinel surveillance system. Main findings were an important role of genital&#x2013;oral transmission routes and HIV serostatus-dependent differences in risk-taking behavior.
From the *Robert Koch-Institut, Berlin, Germany; and in † private practices in Berlin and Frankfurt participating in the MSM-STD-Sentinel Network
The authors thank Michael T. Wright for helpful discussion of the manuscript.
‡Other participants of the MSM-STD-Sentinel Network: Bernd Hegemann, Claudia S. Herzler, Inge Hochscheid, Elke Lauenroth-Mai, Leo Locher, Arne Jessen, Hansjörg Reupke, Frank Schlote, Dietmar Schranz, and Jürgen Wiederholt
Correspondence: Ulrich Marcus, MD, Robert Koch-Institut, Seestrasse 10, 13353 Berlin, Germany. E-mail: email@example.com.
Received for publication November 8, 2004, and accepted June 14, 2005.