Legionella pneumophila is a fastidious, aerobic bacterium that stains poorly and requires special staining techniques. It can cause pneumonia by growing in warm, moist environments like air conditioning systems and shower heads. It is susceptible to erythromycin and other drugs. Several other Bartonella species can cause diseases in humans transmitted via insect bites like trench fever. Bacterial vaginosis is associated with Gardnerella vaginalis, which is detected in wet smears as it covers vaginal cells. It has a fishy odor and high pH. Metronidazole is used to treat it.