Syphilis Resurgence in San Francisco: More of the Same

Background: Following several years of declines in morbidity, San Francisco saw a 56% increase in the number of reported early syphilis cases in 2008 compared to 2007 and the largest number of early syphilis cases since 2005.

Objectives: To examine socio-demographic and sexual and drug using risk behaviors differences between early syphilis cases reported during the recent resurgence compared to a period of endemnicity.

Methods: We compared data from early syphilis cases reported during April 2007 and May 2008 (endemic syphilis) to cases reported from June 2008 to July 2009 (resurgence) using Pearson's χ², Fisher's exact, and Wilcoxon rank sum tests.

Results: There were 449 cases reported from April 2007 to May 2008 and 667 cases reported from June 2008 to July 2009. Cases in both time periods were predominately male (>96%) and over 90% of cases were among men who have sex with men (MSM). Cases during the resurgence period were less likely to have an unknown HIV status (5.3% vs. 10.0%), report methamphetamine (14.1% vs. 36.1%) and report meeting partners through friends (10.9% vs. 15.4%) or at the gym (0.1% vs. 2.0%). Cases during the resurgence period were more likely to be Asian/Pacific Islander (9.8% vs. 6.7%)or Hispanic (19.8% vs. 15.3%).

Conclusions: Although reported early syphilis increased dramatically in San Francisco in 2008, few epidemiologic differences were noted between cases reported during the resurgence and those reported earlier.

Implications for Programs, Policy, and/or Research: Continued epidemiologic monitoring of early syphilis can help inform prevention and control interventions.