Researchers have demonstrated a strong association between the risk of aggressive prostate cancer and a common sexually transmitted infection.

Trichomonas vaginalis infects an estimated 174 million people globally each year, and is the most common nonviral sexually transmitted infection. T. vaginalis can also infect the prostate and be a source of inflammation.

The study, conducted by researchers from Harvard School of Public Health (HSPH) and Brigham and Women’s Hospital, analyzed blood samples from 673 men with prostate cancer and compared infection status of the sexually transmitted infection, T. vaginalis, based on antibody levels to 673 control subjects who were not diagnosed with prostate cancer.