Fig. 2.

Subject area maps with the main MeSH terms associated with different types of pneumonia-(a) “Pneumonia, Aspiration” (b) “Pneumonia, Bacterial, ” (c) “Pneumonia, Ventilator-Associated, ” (d) “Pneumonia, Viral, ” and (e) “Pneumonia, Pneumocystis”

Groupings in the form of “islands” in red tones represent the main clusters of the thematic networks, while the chromatic gradation in yellow and green tones illustrates the areas with a lower density of relations between the MeSH. The spatial distribution of the MeSH and their proximity to each other responds to the intensity of co-occurrence between them