• syphilis
• England
• sexually transmitted infection

After almost two decades of consistent decline, new diagnoses of infectious syphilis in England and Wales are again on the increase.¹ Recent KC60 reports from genitourinary medicine (GUM) clinics indicate that since 1996, diagnoses of primary and secondary syphilis have more than doubled in males (from 84 to 248) and females (32 to 73). The rise was especially marked between 1999 and 2000, when infections rose by over 160% (153 to 248) in males and 130% (55 to 73) in females, and diagnoses attributed to sex between men rose from 52 to 113. Since 1997, when the Bristol outbreak heralded the resurgence of syphilis,² subsequent outbreaks have been reported in the North West, South East, and London regions, such that, by 2000, nearly two thirds of nationally reported cases were diagnosed in these areas. Similar outbreaks have also been reported in several large metropolitan US^{3, 4} and European^{5, 6} cities. Nearly all have occurred in previously low prevalence areas or among population subgroups in which the disease had been largely eliminated. In addition, the outbreaks were characterised by rapid increases in sexual networks with high rates of partner change; links (travel or migration) with high incidence areas; an increasing predominance of homosexual transmission with a high proportion of HIV co-infection among incident cases.