Effect of MI-S topical treatment on viral titers of vaginal swab samples. Mice (n = 10) were intravaginally treated as follows: Group 1, infected, untreated; Group 7, MI-S treatment at 20 mg/ml (233.86 μM), once, 20 min before infection; Group 8, vehicle-only treatment, once, 20 min before infection; Group 2, MI-S treatment at 10 mg/ml (116.93 μM), 3 times daily after infection, for 8 days; Group 4, vehicle treatment, 3 times daily after infection, for 8 days. The viral titers were determined by plaque assay as described in Materials and Methods. (A) Pretreatment; (B) postinfection treatment. Asterisks represent statistically significant differences in comparison to the other groups (P < 0.05) by one-way ANOVA followed by Dunn's multiple comparison test.