An increase in high-risk sexual behavior among men who have sex with men may be the cause of a steady rise in syphilis rates among men during the last 4 years, according to a report from the Centers for Disease Control and Prevention (CDC) on national rates of infection with sexually transmitted diseases (STDs) in 2004.
The annual report, which provides data from mandatory reports of new cases of chlamydia, gonorrhea, and syphilis, presents a nuanced picture of the trends in STD transmission (http://www.cdc.gov/std/). While officials attribute the increase in syphilis cases to a rise in risky behaviors in certain populations, the data did not reflect a corresponding rise in gonorrheal rates, which reached an all time low in 2004. Reported cases of chlamydial infection rose in 2004, but the increase was attributed to improved screening efforts.
Kuehn BM. Syphilis Rates Rise Among Men. JAMA. 2005;294(24):3072-3073. doi:10.1001/jama.294.24.3072