Chinese and US doctors are warning that the sexually transmitted disease, syphilis, is spreading rapidly in China.
Syphilis was largely eliminated in China between 1960 and 1980, but cases have increased more than 30-fold in the last decade.
A report in the medical journal, The Lancet, shows that syphilis is now common in economic boom areas such as Shanghai.
Dr Myron Cohen, director of the Center for Infectious Diseases at the University of North Carolina and a co-author of the study, said urgent intervention is needed.
Syphilis can be treated with antibiotics. Left untreated, it can cause serious damage to the nervous system, heart or brain, and can be fatal.
