With resistance to antibiotics spreading more and more among deadly bacteria, finding alternatives to treat infections is becoming more important. One option is phage therapy, using viruses that infect bacteria to weaken or wipe out pathogens, but this can be tricky. Sometimes it takes too long to prepare an effective population of phage for treatment, and sometimes the target pathogen evolves resistance to the phage too quickly

 

In this study, a phage that was trained, or pre-evolved, to infect specific bacteria more effectively, was able to dominate the population consistently and prevent it from becoming fully resistant. For comparison, against an untrained strain of the same phage, the bacteria developed almost complete resistance after several days.