Abstract: Objective To uncover the possible factors of rapid increasing incidence of syphilis. Methods The clinical data of 100 patients firstly diagnosed as syphilis and their spouses were analyzed. Results There were 65 couples (130 cases) both were infected with syphilis, accounting for 65%. Among these cases, 25 males firstly diagnosed, 15 of them were primary syphilis; and 40 females firstly diagnosed as syphilis, 32 of them were secondary syphilis. Among 65 syphilis couples, 48 spouses were quickly diagnosed as syphilis through contact tracing, but the other 17 spouses were not diagnosed as syphilis until 1~3 months later, and most of them were latent syphilis, accounting for 83.2%(54/65). Chancre, which may be noticed by the patients themselves, was not so common in this group of patients, accounted for only 28.5%(37/130), and mainly in males. Conclusions The infections rate of syphilis between spoused is high, especially latent syphilis, and chancre is low, which might be one of the factors for the rapid spreading of the disease.

Key words: Syphilis, Contact tracing