An inflammation of the vagina caused by flagellate protozoa that infect the vagina, urethra, and Skene’s ducts. Although the individual inflammatory response can include severe vulvar irritation and burning, dysuria, dyspareunia, and profuse, thin, “frothy,” yellow-green to gray discharge, nearly 50% of infected women are asymptomatic. Sixty percent of the sexual partners of infected women share the infection. On inspection, the vulva may appear reddened and edematous. About 10% of infected women exhibit characteristic “strawberry patches” in the upper vagina and upper cervix. Diagnosis is based on seeing the highly motile organism with three to five flagella in a saline wet smear. Oral metronidazole is the organism-specific treatment.