Figure 1.

Alpha-diversity (A) and beta-diversity (B) analyses of fecal bacterial communities from hospitalized infants with acute bronchiolitis. In (A), species richness, equitability, and phylogenetic diversity (mean ± standard deviation) values were compared between RSV-positive (blue-colored) and RSV-negative (yellow-colored) infants’ groups, respectively. In each boxplot, outliers are shown. Except for the phylogenetic diversity index that shows no difference, the observed species, inverse Simpson, and Pielou’s evenness indices are slightly (but not significantly) lower in RSV-positive than in RSV-negative infants. In (B), Bray–Curtis or weighted UniFrac compositional-based distances were computed for RSV-positive (blue-colored) and RSV-negative (yellow-colored) infants’ groups, respectively. The principal coordinate analysis (PCoA) results are presented as two-dimensional ordination plots, which were generated using two (axis1 and axis2) principal coordinates. These results show no significant separation between RSV-positive and RSV-negative infants’ groups. In both (A, B), “positive” and “negative” indicate infants whose nasopharyngeal samples were, respectively, positive for RSV or negative for RSV at molecular testing (see text for details). RSV, respiratory syncytial virus.