The global epidemiology of syphilis in the past century - a systematic review based on antenatal syphilis prevalence

Author Summary: Syphilis rates have varied tremendously between different populations around the world. We conducted a systematic review of syphilis prevalence in pregnant women in 13 populations with available data for the last 100 years. Our findings were that in most populations syphilis prevalence dropped to under 1% before 1960. In the 2 populations from sub Saharan Africa, the syphilis prevalence remained around 6% until 50 years after the introduction of penicillin. Other systematic reviews were utilized to provide syphilis prevalence estimates for all countries with available data for the periods 1990-1999 and 2008. We assessed if there was a correlation between national syphilis prevalence in these periods and five explanatory factors. Only residence in sub-Saharan Africa was associated with syphilis prevalence in both time periods. These findings, considered in conjunction with other types of evidence we review, such as the strong correlations at population level between syphilis prevalence and those of Herpes Simplex Virus-2 prevalence and HIV prevalence, suggest that common risk factors may underpin the spread of all three of these sexually transmitted diseases. Establishing what these factors are is of great importance to improve the health of highly affected populations such as those in sub-Saharan Africa