Asymptomatic Bacterial Vaginosis and Herpes Simplex Virus Type 2 (BV/HSV-2) Shedding Study

Inclusion Criteria: * Women 18-26 years old of age * Only those women who deny symptoms of vaginal discharge and odor but who meet Amsel and Gram stain criteria for the diagnosis of BV will be eligible * Amsel criteria (3 of the following 4 conditions) (10): * Homogenous vaginal discharge * Vaginal pH \> 4.5 * Positive amine (sniff) test * Presence of clue cells in the vaginal fluid * Gram stain criteria (11): * Score: 0-3; classification: normal; vaginal bacteria morphotype: Lactobacillus predominant * Score: 4-6; classification: intermediate; vaginal bacteria morphotype: Lactobacilli reduced * Score: 7-10; classification: BV; vaginal bacteria morphotype: Lactobacillus replaced by Gardnerella and anaerobes * Eligible women will need to test positive for HSV-2 type-specific antibodies. Determination of HSV-2 serostatus will be determined by a point-of-care type-specific immunoassay kit. * Patients capable of providing written informed consent * Patients willing to refrain from the use of intravaginal products (i.e., contraceptive creams, gels, foams, sponges, lubricants, douches, etc.) during the study period * Patients willing to refrain from the use of any systemic or topical genital antiviral medication during the study period * Patients willing and capable of cooperating to the extent and degree required by this protocol Exclusion Criteria: * HSV-2 seronegativity (as determined by the point-of-care immunoassay) * Pregnancy (all women will receive a pregnancy test prior to enrollment) or those women currently not practicing an effective method of birth control * Current Chlamydia trachomatis, Neisseria gonorrhea, or Trichomonas vaginalis infection * Use of prescriptive antiviral treatment for presumed HSV reactivation within the 14 days prior to enrollment * Use of systemic antimicrobials within the past 14 days * History of hypersensitivity or inability to tolerate systemic metronidazole therapy * Nursing mother * Patients with intrauterine devices * Unwillingness to refrain from initiation of antiviral medication during study period * Unwillingness to refrain from use of douche products during study period * Unwillingness to refrain from the ingestion of any alcoholic beverages during the one-week course of oral metronidazole therapy