Background: Whether the natural history of human papillomavirus (HPV) infection is affected by bacterial vaginosis (BV) or Trichomonas vaginalis (TV) infection has not been adequately investigated in prospective studies.
Methods: Human immunodeficiency virus 1 (HIV-1)-infected (n=1763) and high-risk HIV-1-uninfected (n=493) women were assessed semiannually for BV (by Nugent's criteria), TV infection (by wet mount), type-specific HPV (by polymerase chain reaction with MY09/MY11/HMB01 HPV primers), and squamous intraepithelial lesions (SIL) (by cytological examination). Sexual history was obtained from patient report at each visit. Risk factors for prevalent and incident HPV infection and SIL were evaluated by use of multivariate models.
Results: BV was associated with both prevalent and incident HPV infection but not with duration of HPV infection or incidence of SIL. TV infection was associated with incident HPV infection and with decreased duration and lower prevalence of HPV infection. TV infection had no association with development of SIL. Effects of BV and TV infection were similar in HIV-1-infected and high-risk HIV-1-uninfected women. HIV-1 infection and low CD4(+) lymphocyte count were strongly associated with HPV infection and development of SIL.
Conclusions: BV and TV infection may increase the risk of acquisition (or reactivation) of HPV infection, as is consistent with hypotheses that the local cervicovaginal milieu plays a role in susceptibility to HPV infection. The finding that BV did not affect persistence of HPV infection and that TV infection may shorten the duration of HPV infection helps explain the lack of effect that BV and TV infection have on development of SIL.