Infectious Syphilis: The Return of an Epidemic

Robert B. Stroube, MD, MPH


May 12, 2008

In This Article

Return of an Epidemic: 1982, 1990

By 1982, a new syphilis epidemic peaked. This was mostly in men, in the 20- to 29-year-old age group, in the South, and in blacks with a black-to-white ratio of 13.2:1.[6] This was at the beginning of the national AIDS epidemic and involved men who have sex with men (MSM). As the HIV situation worsened, the syphilis picture improved. This was probably related to the severe mortality and morbidity caused by HIV and by the subsequent widespread institution of safe sex behaviors.

The next syphilis epidemic peaked in the early 1990s. This time women were as affected as men; the black-to-white ratio was 62:1, and it involved the entire country -- greatest initially in the West, then spreading to the South and Northeast, and then spreading to the Midwest.[6] Cases were mostly in black heterosexuals in urban areas and in the rural South, and were linked to the use of "crack" cocaine and the exchange of sex for drugs.[6,7,8]

By 1990, there were more than 50,000 cases of primary and secondary syphilis in the United States, but by 1997 the numbers had dropped to less than 10,000 cases. Again, optimism flared that this was a potential window of opportunity when the endemic transmission of syphilis in the United States could be eliminated. The basis for this was that:

  • 15% of US counties accounted for 80% of the reported infectious syphilis cases;

  • Syphilis is an exclusively human pathogen;

  • There was effective therapy that both cured and ended the disease transmission -- a single injection of a widely available, relatively cheap antibiotic;

  • The organism was relatively slow-growing; and

  • There was no clinically significant antimicrobial resistance.[9]

Consequently, the Public Health Service in October 1999 released the "National Plan to Eliminate Syphilis.[10]" In 2000, the number of infectious cases of syphilis reported dropped to its lowest rate since national reporting began in 1941.[4]

However, the situation changed rapidly, and in 2001 the number of cases reported again began to climb and has increased every year since then. Case rates in women and infants continued to go down, but there has been a dramatic increase in the number of cases of primary and secondary syphilis in MSM.[1] Paradoxically, as highly active antiretroviral therapy became available for HIV, the number of syphilis cases increased. This was linked to an increase in unsafe sex practices as the fear of HIV lessened. Data from King County, Washington, demonstrated the role of MSM in this outbreak: 141 cases of primary and secondary syphilis in MSM per 100,000; 683 in MSM with HIV per 1000; and < 1 per 100,000 in heterosexuals.[4]


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.