that seems like a good thing. they only infect bacteria, not humans

phages are found in large quantities in mucus, where they seemingly contribute to the barrier function of mucus by preying on any bacteria that try go cross

https://pubmed.ncbi.nlm.nih.gov/23690590/

https://www.pnas.org/doi/10.1073/pnas.1508355112

https://journals.asm.org/doi/10.1128/mbio.01984-19

this might be adaptable for therapeutics

https://www.nature.com/articles/s41467-024-48560-2

https://www.nature.com/articles/s42003-024-07269-0