Syphilis Rates Climb Among Gay and Bisexual Men

ATLANTA, April 26 -- After a decade of decline, syphilis rates rose by 19% from 2000 through 2003, largely because of cases among men who have sex with men, according to a CDC study.

From 1990 to 2000, primary and secondary syphilis rates fell by 90% among men and 89% among women, perhaps because of a nationwide campaign aimed at heterosexuals and a decrease in the use of crack cocaine, researchers reported online in the June issue of the American Journal of Public Health.

The 19% increase in the rate from 2000 to 2003 reflected a 62% increase among men, but a 53% decrease among women, said James D. Heffelfinger, M.D., M.P.H., of the CDC, and colleagues.

In 2003, it appears that most syphilis cases reported annually occurred among gay and bisexual men, as shown by the decline in cases among women, increasing rates among men, and recent reports of syphilis outbreaks in the male gay community, the researchers said.

The study did not look past 2003, but continued case statistics suggest the trends might have continued through 2005, Dr. Heffelfinger said. For example, 8,724 new cases of syphilis were recorded in 2005, compared with 7,177 cases in 2003.

From 2000 though 2003, the largest increase in cases, by gender and race/ethnicity, occurred among white men. The substantial increases in cases in this group and estimates of male-to-male cases (based on the steep rise in the male-female case ratios) suggest that gay and bisexual men account for most of this recent national upsurge, the researchers said.

From 1990 through 2003, the rate of syphilis in the U.S. had decreased 82% among men and 95% among women, leading to optimism that syphilis could be eliminated in the U.S. Not longer, the researchers found.

The turn-about in rates suggests that substantial changes in sexual behavior, especially reduced concern about HIV and the need for safe sex, have facilitated syphilis transmission among gay and bisexual men in many industrialized nations, not just the U.S.

Main findings:

• Syphilis rates tripled in the northeast and increased 170% in the west, but declined by 20% and 16% in the midwest and south respectively, partly due to a decline among African-American women.
• Although rapid and dramatic changes in syphilis profiles occurred in large U.S. cities, when urban cases from 63 large cities were excluded, there was still a threefold increase in the male-female ratio for the rest of the nation.
• From 2000 through 2003, the largest increase in cases by gender and race/ethnicity occurred among white men.
• Although up to 2000, rates remained higher for African Americans and Hispanics, by 2003, for the first time since 1981, more cases were reported among whites than among African Americans.
• Since the late 1990s, outbreaks have occurred in the United Kingdom and many European countries, and, as in the U.S., and a high proportion of cases have involved men who have also been infected with HIV.

Addressing the HIV connection, the researchers said that although it is easy to cure syphilis, the risk of HIV transmission is of particular concern because syphilis increases transmission of HIV three- to fivefold, and a high percentage of gay men involved in recent syphilis outbreaks were also infected with HIV.

Limitations of the study, the researchers wrote, included incomplete reporting of syphilis cases, variations in data collection and recording within STD control programs, and the absence of information about the sexual orientation and gender of partners.

Because national case data do not include information about partner gender, the investigators used a model that estimated the cases on the basis of increases in the male-female ratios. Thus, these estimates must be interpreted with caution, they said, since these ratios may be elevated for a variety of reasons-outbreaks between female prostitutes and men, for example--in addition to male-female ratios.

The primary challenge for eliminating syphilis is to continue past successful efforts and to prevent and control the disease in gay men, the investigators said.

Among the key interventions for gay and bisexual men suggested by the updated 2006 National Syphilis Elimination Plan are:

• Collecting and reporting data on the gender of sexual partners and the sexual preference of persons diagnosed with syphilis;
• Developing Internet-based interventions to engage gay individuals with syphilis and facilitate partner notification;
• Enhancing syphilis education and sexual health within STD clinics and the community;
• Using provider outreach programs and improving the quality of clinical management;
• Expanding access to syphilis screening at STD-care facilities and outreach settings;
• Raising awareness about the current syphilis epidemic and its implications for transmission and acquisition of HIV;

Promoting efforts to reduce high-risk sexual behaviors, and educating men to recognize symptoms and signs of syphilis and understand the importance of seeking early medical care.

National efforts to mobilize the gay community to take an active role in these efforts are crucial. Training providers to improve skills in diagnosing and treating syphilis, screening sexually active gay and bisexual men routinely for syphilis and other STDs, and providing HIV counseling and testing are all critical for controlling syphilis in this group, Dr. Heffelfinger's team concluded.