Objectives: To understand trends and epidemiological features of syphilis over the recent years in China and provide a scientific basis for developing prevention strategies. Methods: From 1985 to 2000, syphilis case-reporting data collected from all provinces, autonomous regions and municipalities were analyzed by applying epidemiological methods. Results: (1) Epidemic trends: syphilis incidence has steadily risen in China from 1985 to 2000, especially after 1993, when it assumed an exponential growth pattern. 80,406 cases of syphilis were reported in the country in 1999, which was almost 40 times the number reported in 1993. During the period of 1993-1999, the annual average growth of the syphilis incidence rate was 83.55%. Perhaps due to a recent national law enforeement campaign, the number of reported syphilis cases dropped slightly in 2000. (2) Geographical distribution: Syphilis spread from coastal, open cities (especially some cities in Fujian province) to inland urban areas, then to rural areas.Regions with a high incidence rate of syphilis in China were the Minjiang, Yangtze, and Zhujiang River Deltas, Beijing and Tianjin municipalities, and Northeast China. There was a significant difference of syphilis incidence rates and growth rates between these areas. A serious epidemic occurred in some areas, with an incidence rate reaching over 200 cases out of 100,000. (3) Population distribution: the ratio of male and female cases gradually changed from 1.57:1 in 1993 to 1.02:1 in 2000. The rate was the highest in the 20-29 age group and the lowest in 10-14 age group. A great difference existed in prevalence between different population groups and different areas,and some areas with serious epidemics had high prevalence rates even amoung the general population. (4) Clinical stage of syphilis: Primary and secondary syphilis cases have been dominating with a percentage of 90% of all syphilis cases. Primary syphilis was the most common in males and secondary syphilis in females. Secondary and latent syphilis c
