FIGURE 6.

Alpha and beta diversity comparisons in oral and lung communities, stratified by respiratory specimen culture positivity. (A) Alpha diversity comparisons in oral communities, showing statistically significantly lower richness and evenness in culture-positive samples compared to culture-negative ones (p = 0.002). (B) Bray–Curtis dissimilarity indices comparison in 4 groups: red circles for oral communities of culture-positive samples, blue circles for oral communities of culture-negative samples, red triangles for lung communities of culture-positive samples, blue triangles for lung communities of culture-negative samples. Permanova indicates significant differences overall, but oral and lung communities are overlapping when stratified by respiratory sample culture positivity, indicating that oral communities in culture-positive cases were taxonomically more similar to their corresponding culture-positive lung communities, rather than the oral communities of culture-negative cases.