Su S, et al. - A cross-sectional study was conducted to illustrate the differences in sexual practices among people with various drug administration patterns. For this analysis, researchers recruited a detoxification center in Southwest China, a part of the Chinese national sentential surveillance network for hepatitis C virus (HCV), HIV and syphilis infections. During 2015, 610 newly enrolled injection drug users (IDUs) from the detoxification center were involved. Findings demonstrated that the daily drug injecting frequency of heroin-only and poly-drug users was negatively associated with sexual activities. It was noted that synthetic drug (SD)-only drug users reported the highest proportion of engaging in sexual activities. HCV, HIV, and syphilis infection prevention and treatment programs targeting priority subgroups of IDU in China should be promoted.