Fig. 3
Gross morphology and bacterial detection of M. ulcerans-infected mouse tails with and without topical application of hydrated clay mixtures. Disease advancement and gross morphology of M. ulcerans-infected tails following 22 d of daily cleansing with sterile dH2O (no treatment) (a) or daily topical applications of hydrated antibacterial CB09 clay (b). After 22 d of topical treatment with the hydrated CB09 clay mixture, M. ulcerans survival was determined by collecting the tails from infected mice, processing the samples as described in the methods, and inoculating supplemented M7H10 agar to determine viable CFU per gram of tissue for each animal sample (c). Error bars represent the SD from three viable CFU determinations for each animal sample. The average (± SD) number of M. ulcerans cells, as determined from five infected animals on day 1 post-infection, is shown for comparison. The limit of detection is 10 CFU. NT, no treatment; CT, clay treatment. ***, p < 0.001; ****, p < 0.0001; ANOVA, Tukey’s multiple comparisons