Venue-Based Comparison of STI Prevalence Rates Among MSM, 2009-2011

Background: MSM in the United States continue to be disproportionately impacted by STIs.  Identifying high-yield settings to screen MSM for STIs is necessary for resource-limited programs.

Objectives: We compared STI positivity among MSM screened at three Howard Brown Health Center sites (Walk-in STI clinic, primary care, and outreach) to determine which testing venues yielded the highest case rates.

Methods: Data were routinely collected from electronic medical record abstraction and as part of an on-going sentinel surveillance project, the Sexually Transmitted Diseases Surveillance Network (SSuN).  Chi-square tests were used to compare positivity by testing venue.

Results: From January 2009-June 2011, 7,522 MSM were screened for gonorrhea, chlamydia, and/or syphilis at 14,063 visits.  Overall positivity was 6.4% (450/7072) for urogenital gonorrhea, 5.0% (352/7075) for urogenital chlamydia, and 5.2% (666/12859) for syphilis.  New syphilis case positivity was higher at STI clinic (5.5%, 357/6489) and primary care (5.4%, 297/5472) than outreach (1.3%, 12/898); p<0.001.  Gonorrhea and Chlamydia positivity were highest in STI clinic (10.3%, 300/2907; 7.0%, 203/2907), followed by primary care (4.3%, 122/2852; 4.0%, 115/2855), and outreach (2.1%, 28/1313; 2.6%, 34/1313); p<0.001.  Symptoms were strongly associated with STI diagnosis, and while a higher proportion of STI clinic patients presented with symptoms than those screened through outreach, symptoms did not fully explain variation in positivity across sites.

Conclusions: Positivity was lower among MSM screened through outreach than among those screened through STI clinic or primary care.  Resource-limited programs seeking to maximize efficiency of disease detection and control should target STI clinic and primary care settings, though the prevalence of infection detected through outreach venues warrants continued screening. 

Implications for Programs, Policy, and Research: Further research should examine predictors of infection among MSM seeking care in medical and non-medical settings.   A better understanding of the role of outreach settings for screening MSM who may not otherwise seek medical care is needed.