Figure 1.

Bibliometric parameters of microbiome studies. Representations were limited to the four most abundant microbiomes (urogenital tract in purple, skin microbiome in green, gastrointestinal tract in red and respiratory microbiome in blue). The number of publication focusing on microbiome increased slightly until 2011, after which Next Generation Sequencing (NGS) technologies became more widely available. Microbiome publications focused mainly on gastrointestinal microbiome; the other three niches being studied in the same proportions.