August 2, 2011
Rates of primary and secondary syphilis disproportionately increased in recent years among black, Hispanic, and young men who have sex with men, CDC researchers reported on Monday. Syphilis has been on the rise since 2000, and studies suggested MSM accounted for a majority of the new cases. However, the sex of the sexual partners was not reported for national-level syphilis data until 2005.
While the decade's initial outbreak especially hit MSM in their 30s, the new study of 27 states found the largest increase in the 2005-08 period to be MSM in their teens and 20s. In 2008, MSM ages 20-29 had the biggest increase in syphilis, to about 12 cases per 100,000.
That same year, the absolute increases in syphilis rates among black and Hispanic MSM were 8.0 and 2.4 times, respectively, the rate for white MSM. Black MSM had 19 cases of syphilis per 100,000 population, Hispanic MSM had over 7 cases per 100,000, and white MSM had 4 per 100,000.
In 2000, the US syphilis rate was 2.1 cases per 100,000 population. By 2009, men had a rate of just under 8 syphilis cases per 100,000 population, and women had 1.4 cases per 100,000.
The magnitude of the racial disparities is concerning, said Dr. John R. Su, a CDC medical epidemiologist. Reasons for the disparities are hard to pin down, but they could be fueled by poorer income, educational levels, and health care access, he said. Some recent studies suggest an uptick in unprotected sex and multiple partners among MSM.
Education and screening efforts need to target MSM where they are: online, at clubs, bars, and bathhouses, the Boston-based Fenway Institute's Dr. Kenneth H. Mayer and Matthew J. Mimiaga wrote in an accompanying editorial. "Many MSM with newly diagnosed syphilis or HIV met their sexual partners recently on the Internet," they noted.
"First, you have to know you're at risk," said Su, who cited peer educators as another promising approach. Getting tested for STDs at least annually, practicing monogamy with a partner who gets tested, and consistent condom use reduce the risk of syphilis and other STDs.
The full report, "Primary and Secondary Syphilis Among Black and Hispanic Men Who Have Sex with Men: Case Report Data from 27 States," and the editorial, "Resurgent Syphilis in the United States: Urgent Need to Address an Evolving Epidemic," were published in Annals of Internal Medicine (2011;155:145-151 and 192-193, respectively).