The antimicrobial susceptibilities, biochemical properties, and cultural characteristics of six strains of Weeksella virosa (formerly group IIf) were determined. The main characteristics of this non-fermentative organism were production of cytochrome oxidase, gelatinase, and indole, but a lack of saccharolytic activity. A study was then made of the isolation rates of Weeksella virosa from high vaginal swabs from 300 women: a healthy control group (n = 100), a general group with symptoms of vaginal infection (n = 100), and 100 women from a remand centre, where likelihood of exposure to sexually transmitted disease might be expected to be higher. The incidence of Weeksella virosa was found to be 2% in the first two groups. This suggests that, irrespective of the presence of pathogens, the incidence of the species in the general female population is around 2%. A much higher incidence (15%) was found in the third group, suggesting sexual transmission of the organism.