Decoding the human phageome helps to unravel microbial dynamics in health and disease.

Bacteriophages are the most abundant biological entities on Earth-equally abundant within the human body. Their potential impacts on host function and homeostasis are becoming increasingly important in biomedical and microbiological research. Phage abundance and diversity often signal changes in the resident bacterial microbiome, but they can also regulate microbiome dysbiosis, help identify pathogenic bacterial candidates, and provide clues to understand the disease-related microbiome changes and the role of the phageomes in health and disease contexts. In a recent minireview, Rybicka and Kaźmierczak (Appl Environ Microbiol 91:e01788-24, 2025, https://doi.org/10.1128/aem.01788-24) synthesize the current understanding of phage communities across the human gut, oral cavity, skin, respiratory, and urogenital tracts, seeking connections with health and disease status.