title: Prospective study of correlates of vaginal Lactobacillus colonisation among high-risk HIV-1 seronegative women.
abstract: OBJECTIVE
  Vaginal colonisation with Lactobacillus species is characteristic of normal vaginal ecology. The absence of vaginal lactobacilli, particularly hydrogen peroxide (H(2)O(2))-producing isolates, has been associated with symptomatic bacterial vaginosis (BV) and increased risk for HIV-1 acquisition. Identification of factors associated with vaginal Lactobacillus colonisation may suggest interventions to improve vaginal health.
  
  
  METHODS
  We conducted a prospective cohort study of correlates of vaginal Lactobacillus colonisation among Kenyan HIV-1 seronegative female sex workers. At monthly follow-up visits, vaginal Lactobacillus cultures were obtained. Generalised estimating equations were used to examine demographic, behavioural and medical correlates of Lactobacillus isolation, including isolation of H(2)O(2)-producing strains.
  
  
  RESULTS
  Lactobacillus cultures were obtained from 1020 women who completed a total of 8896 follow-up visits. Vaginal washing, typically with water alone or with soap and water, was associated with an approximately 40% decreased likelihood of Lactobacillus isolation, including isolation of H(2)O(2)-producing strains. Recent antibiotic use, excluding metronidazole and treatments for vaginal candidiasis, reduced Lactobacillus isolation by approximately 30%. H(2)O(2)-producing lactobacilli were significantly less common among women with Trichomonas vaginalis infection and those who were seropositive for herpes simplex virus type 2. In contrast, H(2)O(2)-producing lactobacilli were significantly more common among women with concurrent vaginal candidiasis.
  
  
  CONCLUSIONS
  Modifiable biological and behavioural factors are associated with Lactobacillus colonisation in African women. Our results suggest intervention strategies to improve vaginal health in women at high risk for HIV-1.
authors.affiliation: Department of Global Health, University of Washington, Seattle, Washington 98104, USA. jbaeten@u.washington.edu
authors.forename: J M
authors.initials: JM
authors.lastname: Baeten
authors.forename: W M
authors.initials: WM
authors.lastname: Hassan
authors.forename: V
authors.initials: V
authors.lastname: Chohan
authors.forename: B A
authors.initials: BA
authors.lastname: Richardson
authors.forename: K
authors.initials: K
authors.lastname: Mandaliya
authors.forename: J O
authors.initials: JO
authors.lastname: Ndinya-Achola
authors.forename: W
authors.initials: W
authors.lastname: Jaoko
authors.forename: R S
authors.initials: RS
authors.lastname: McClelland