Methods are described for increasing levels of healthy vaginal bacteria by treating the vaginal mucosa with bacteriocins derived from Lactobacillus paragasseri, Lactobacillus gasseri, and other bacterial strains. The bacteriocins are surprisingly advantageous as being selectively active against Lactobacillus iners but relatively inactive against H2O2-producing Lactobacillus species. Because L. iners is involved in the onset and maintenance of vaginal dysbiosis, selective removal of this bacterium from the vaginal microbiome treats or prevents conditions associated with vaginal dysbiosis, such as bacterial vaginosis and its sequelae.