Rethinking phage-bacteria-eukaryotic relationships and their influence on human health

There is a rapidly growing body of research demonstrating the unique and often surprising mechanisms by which bacteriophages, specialized viruses of bacteria, can influence human health and disease states. This can occur directly by shaping their bacterial host's ecology through top-down pressure or via more indirect routes, including influencing the human body's metabolism or immune system. These microbial interactions can affect health and disease states in both the local environment or by influencing the body's distal organs or systems. Here we provide an update on the current understanding of bacteriophages' influence on human health within the context of tripartite symbioses with their bacterial and human hosts.