FIG 2.

MAYV BeH407 in adult wild-type C57BL/6J mice. (A) Viremia in adult female C57BL/6J mice (6 to 24 weeks old) infected with 10⁴, 10⁵, or 10⁶ TCID₅₀ or mock-infected with PBS, with n = 4 to 6 mice per group. (B) Percentage increase in foot height × width (relative to day 0) for mice infected as described for panel A, with n = 8 to 12 feet from 4 to 6 mice per group per time point. (C) Photographs showing examples of feet on day 6 postinfection, illustrating foot swelling in MAYV-infected groups compared to the mock-infected control group. H&E staining of muscle (M), tendon (T), synovial space (SS), and subcutaneous edema (*) in foot sections from 6- to 24-week-old C57BL/6J wild-type female mice infected as described for panel A. Black ovals indicate some of the areas containing inflammatory infiltrates in the muscles. Inflammatory infiltrates near and in tendon areas are visible, as well as inflammatory infiltrates near joint tissues. (D) Ratio of nuclear (purple) to nonnuclear (red) staining of H&E-stained foot sections (a measure of leukocyte infiltration). Data from 4 to 6 feet from 2 to 3 mice per group, with 3 sections scanned per foot and values averaged to produce one value for each foot. Statistical analysis used the Kolmogorov-Smirnov test. Multiple test correction was not applied. Error bars indicate one standard error of the mean.