The Neutral Vaginal pH in Mice That Is Typical of Most Mammalian Species Should Not Deter Research Using Experimental Murine Models of Vaginitis.

For over three decades, investigators have used estrogen-dependent rodent animal models to study pathogenesis of vulvovaginal candidiasis (VVC) or test promising antifungal drugs. One disparity not well publicized is that rodents maintain near neutral vaginal pH, which is in contrast to the acidic vaginal pH in women. In this issue of , Miao and coworkers (J. Miao, H. M. E. Willems, and B. M. Peters, Infect Immun 89:e00550-20, 2021, https://doi.org/10.1128/IAI.00550-20) have addressed the topic with an elegant study that not only confirms the near neutral vaginal pH in mice, but also reveals a stable vaginal pH that is not influenced by exogenous reproductive hormones or vaginal colonization. More importantly, they make a convincing argument that the neutral vaginal pH should not deter using the model for research purposes. This commentary further emphasizes the points made and attempts to provide a more global perspective on this interesting property of the animal model.