Yeast infections generally have no odor. Unlike bacterial vaginosis or yeast infections, trichomoniasis is a sexually transmitted disease. It is caused by a parasitic organism called a trichomonad. The organism can survive on moist towels, washcloths, or bathing suits, although transmission by these nonsexual routes is extremely rare. Symptoms usually include a yellow-green vaginal discharge with a foul odor, itching, burning, irritation, and painful urination.
Trichomoniasis is the least common of the three vaginal infections.
A physician or qualified health care provider can detect bacterial vaginosis with a few simple tests. Vaginal secretions in women with bacterial vaginosis often appear milky white or gray, thin, and might be increased in amount. A chemical called potassium hydroxide is added to vaginal secretions, then sniffed for foul odor. There may also be a risk of gynecologic complications. Bacterial vaginosis has been associated with abnormal Pap smear results, including inflammation and other cervical changes.