How Phage Therapy Kills Superbugs: Weaponizing Viruses to Fight Infections

Turning viruses into precise, powerful treatments

Phage therapy—using specific viruses to fight difficult bacterial infections—shows great promise as a tool for solving the problem of antibiotic-resistant bacteria (also called superbugs). Here at Yale Medicine, the experimental treatment has already been used to benefit some patients—good news given that antibiotic-resistant bacteria are now considered one of the most alarming public health problems. A recent report from the Centers for Disease Control and Prevention (CDC) blames the problem for a death every 15 minutes here in the U.S.

Since the discovery of penicillin, doctors have used antibiotics to cure people of once lethal bacterial infections. But now we know that, over time, bacteria have the ability to protect themselves by evolving and becoming stronger and more complex (called antibiotic resistance). Researchers have found that viruses can be a powerful tool that can be used against them.  

Specifically, a type of friendly virus called bacteriophage (sometimes referred to as just phage) can be weaponized to fight even the most difficult bacterial infections. This works because, unlike viruses that make us sick, phages can only infect bacteria—and they are even selective about which bacteria they target. These phages are not rare; phages come from nature and are found nearly everywhere in the world. This gives them the power to become, potentially, superheroes in our battle against resistant superbugs.  

This video explains how Yale research scientist Benjamin Chan, PhD, collaborates with Yale Medicine doctors like Jonathan Koff, MD, to not only develop phage therapy, but to use them to treat people who are especially vulnerable to infection (for instance, patients with cystic fibrosis). The goal is to develop a library of effective treatments for specific types of bacteria and make these treatments available to patients with antibiotic-resistant infections when other options are exhausted.  

“It’s definitely the dream,” says Chan. “It’s fantastic to go from doing basic research and then bringing it to a patient in the clinic.”

To learn more, visit yalemedicine.org.