The rate of primary and secondary syphilis in the United States among men who have sex with men is 106 times that of men who have sex with women only, researchers said.
The disparity is even greater — 167.5-fold — when men who have sex with men (MSM) are compared with women.
“These data highlight the disproportionate impact of syphilis among MSM and underscore the need for innovative and targeted syphilis prevention measures at the state and local level, especially among MSM,” Alex de Voux, PhD, an epidemic intelligence service officer at the CDC’s Division of STD Prevention, and colleagues wrote in MMWR.
Although data on the nationwide prevalence of syphilis were already available, the researchers sought to estimate the prevalence of infection in individual states among MSM as compared with other populations using a combination of census and population-based survey data.
Among their sources were reports of primary and secondary syphilis in 2015 to the National Notifiable Diseases Surveillance System (NNDSS), through which the CDC monitors the incidence of diseases.
Forty-four states reported the sex of the patient’s sex partner to the NNDSS in at least 70% of male cases. From the data, the researchers found that the rate of primary and secondary syphilis among all men was 17.5 per 100,000 population, compared with 309 per 100,000 among MSM, 2.9 per 100,000 among men who have sex with women only and 1.8 per 100,000 among women.
When measured by state, the rates ranged from 73.1 per 100,000 in Alaska to 748.3 per 100,000 in North Carolina.
De Voux and colleagues also found that rates were highest in Southern and Western states. Four of the five states with the highest are in the South; they are Louisiana, Mississippi, North Carolina and South Carolina.
In all, MSM accounted for 12,118 (60.8%) of syphilis cases nationwide in 2015. Of those, 10,942 (54.9%) were men who have sex with men only, and 1,176 (5.9%) were men who have sex with men and women.
The researchers concluded that health officials and clinicians must place a special focus on MSM when addressing syphilis.
“Because MSM represent the majority of all primary and secondary syphilis cases, the success of syphilis prevention programs is contingent upon addressing the high rates of syphilis among MSM,” they wrote. “It is important that both private and public health care providers recognize the signs and symptoms of syphilis, conduct a comprehensive sexual history, screen all sexually active MSM for syphilis at least annually and provide timely treatment according to national STD treatment guidelines.” – by Joe Green
The researchers report no relevant financial disclosures.