People at increased risk for syphilis – including asymptomatic, nonpregnant adolescents and adults who have ever been sexually active and are at high risk for the disease – should be screened for it, according to a reaffirmation by the United States Preventive Services Task Force of its 2016 recommendation of syphilis screening for people at increased risk for infection.
“Using a reaffirmation process, the authors, led by Carol M. Mangione, MD, MSPH, of the University of California, Los Angeles, wrote in JAMA.
Reported cases in the United States of primary and secondary syphilis – a sexually transmitted infection caused by the bacterium Treponema pallidum that can damage the brain, nerves, eyes, and cardiovascular system if left untreated – increased from a low of 2.1 cases per 100,000 people in 2000 and 2001 to 11.9 cases per 100,000 in 2019, the authors reported. In 2019, men accounted for 83% of all primary and secondary syphilis cases, and men who have sex with men (MSM) accounted for 57% of all primary and secondary syphilis cases in men. Screening and follow-up treatment can cure syphilis and prevent complications.
To help them evaluate the effectiveness and safety of screening, the USPSTF authors reviewed the literature and visually displayed key questions and linkages to interventions and outcomes, Michelle L. Henninger, PhD, Sarah I. Bean, MPH, and Jennifer S. Lin, MD, MCR, of the Kaiser Permanente Evidence-based Practice Center in Portland, Ore., noted in a related evidence report of the post-2016 recommendation data.
Reaffirming its 2016 recommendation, the USPSTF now advises clinicians to:
Assess risk:
- Clinicians should know how common syphilis is in their community and assess their patient’s individual risk.
- Risk for syphilis is higher in MSM, people with HIV infection or other STIs, and those who use illicit drugs or have a history of incarceration, sex work, or military service.
Screen and confirm by testing:
- Traditional screening algorithm: Start with a nontreponemal test such as Venereal Disease Research Laborator or rapid plasma reagin. If positive, confirm result with a treponemal antibody detection test, such as T. pallidum particle agglutination.
- Reverse sequence algorithm: Screen with an initial automated treponemal test such as enzyme-linked or chemiluminescence immunoassay. If positive, confirm result with a nontreponemal test.
Consider screening interval:
- Evidence on optimal screening intervals is limited for the general population, but MSM and people with HIV may benefit from screening yearly or every 3-6 months if they remain at high risk.
The authors acknowledged that primary and secondary syphilis rates are higher in Blacks, Hispanics, Native Americans/Alaska Native, and Native Hawaiians/Pacific Islanders, and that the disparities are primarily driven by social determinants of health including differences in income, education, and access to coverage and care.
They added that differences in sexual networks also play a role in disparities and that sexually active people in communities with higher STI rates may be more likely to become infected.