Trichomoniasis is a sexually transmitted disease caused by a parasite. It affects both women and men, but symptoms are more common in women. Symptoms in women include a green or yellow discharge from the vagina, itching in or near the vagina and discomfort with urination. Most men with trichomoniasis don't have any symptoms, but it can cause irritation inside the penis.
Sources
MedlinePlus - Trichomoniasis
