Temperate phages increase antibiotic effectiveness in a <i>Caenorhabditis elegans</i> infection model

Bacterial viruses (phages), which can go dormant in their host, are not considered suitable for phage therapy. Building on prior work showing antibiotics synergize with these phages by preventing dormancy, we test the ability of temperate phages-in combination with antibiotics-in an animal model of infection. Not only were the combinations extremely effective at doses that would do nothing alone, even when the bacterium was resistant to the antibiotics-but we also found that whether the dormant phage pre-existed (as it does in about 75% of bacteria) or not determined the success of antibiotic treatments, suggesting many antibiotic treatments are already a form of "accidental" phage therapy.