Gardnerella vaginalis bacteria. Coloured transmission electron micrograph (TEM) of Gardnerella vaginalis bacteria. This bacteria is found in the human urinary and genital tract. Increased numbers are associated with non-specific vaginitis (also known as bacterial vaginosis) in women. This vaginal infection is sexually transmitted and causes a watery, non-irritating discharge with a characteristic fishy odour. Treatment is with the antimicrobial drug metronidazole. Magnification:x39,900 at6x7cm size. x140,000 at 7.5x9.5 inch size.