O11.3 Extreme heterogeneity in vaginal microbial kinetics within and across women

Introduction Incident bacterial vaginosis (BV) is associated with a shift in the vaginal microbiota from lactobacillus predominant to a diverse community of anaerobic bacteria The kinetics of this shift are poorly described. We sought to identify the dynamics of incident BV. Methods Twenty women with frequent BV (u003e3 episodes per year) self-collected vaginal swabs every 8 hours for 60 days. Swabs were analysed with quantitative PCR targeting Lactobacillus iners, Lactobacillus jensenii, Lactobacillus crispatus, Gardenerella vaginalis, Atopobium vaginae, bacterial vaginosis associated bacterium-2 (BVAB2), and Megasphaera spp . We defined bacteria as absent, low (4 DNA copies), moderate (104–108 DNA copies) or high-level (108–1011 DNA copies). Participants kept detailed diaries regarding sexual behaviour, menstruation, antibiotic use and vulvovaginal symptoms. Results We noted three states of the vaginal microbiota: three women had high-level lactobacilli with intermittent, transient low-level G. vaginalis throughout the sampling period (State 1); five women had high-level lactobacilli with persistent, fluctuating low to moderate-level G. vaginalis and other BV associated anaerobic species throughout the sampling period (State 2); two women had polymicrobial colonisation with high-level G. vaginalis and other BV associated species, and intermittent, transient low-level, or persistent moderate-level Lactobacillus jensenii and crispatus throughout the sampling period (State 3). Ten women shifted between States 2 and 3 on at least one occasion. Extremely rapid transition from State 2 to 3 over. Conclusions The vaginal microbiota is extremely dynamic and BV develops over narrow time intervals. Low-levels of BV associated species in the vagina may be a risk factor for rapid, incident BV. Future studies will identify drivers of shifts in the vaginal bacterial biota.