Phages are viruses that are the natural enemies of bacteria. The word ‘bacteriophage’ means “bacteria eater.” Phages exist anywhere bacteria are found. There is a phage for each kind of bacteria, whether it is Escherichia coli (E. coli) or Clostridium difficile (C. diff). These viruses attack the specific bacteria, hijack their metabolic processes, and destroy them. They exist to keep bacteria in check. Modern medicine has just begun to research ways to use phages as an alternative to antimicrobial medicine as resistance to these drugs is rising globally.
Deeper dive
Phage therapy involves the use of bacterial viruses (bacteriophages) to treat bacterial infections. This therapy was discovered more than a century ago, but never caught on as worldwide topic of medical research because anti-microbial medications became the preferred and easier method for treating bacterial infections. With the rise of antimicrobial resistance, there is a growing interest in harnessing this natural enemy of bacteria as an alternative to antibiotics.
Phages exist anywhere there is bacteria and are one of nature’s ways of keeping bacteria from growing out of control. They hijack bacteria’s genetic code and then destroy it.
Scientists at the Pasteur Institute in Paris first discovered phages in the early 20th century. A Georgian scientist, George Eliava, took the discovery back to his country, where the Eliava Institute was created. Phages were used through the Soviet Union during and after World Work Two to treat infections, but the scientific community outside the USSR mostly ignored their work. The challenge is that phages are particular to the bacteria. There is a phage for each strain of Escherichia coli (E. coli) or Clostridium difficile (C. diff), but they aren’t interchangeable. Antibiotics, however, can kill many strains of bacteria, and they became the preferred method for treating infections globally.
With the rise of antimicrobial resistance, phage therapy is getting more attention. In 2010, Texas A & M opened a Center for Phage Technology, the University of California at San Diego founded the Center for Innovative Phage Applications and Therapeutics, the University of Pittsburgh has built a research team around phage therapy and so has the US Naval Medical Research Center.
Researchers are now making use of advances in genetic technology to build phages that can attack bacteria. The process is time-consuming and expensive. It requires scientists to find the exact phage that will kill the bacterial strain. Among the places scientists look for phages that attack pathogens dangerous to humans include sampling sewage. The research has advanced far enough to have saved several people who were dying from antibiotic resistance.
See this June 2022 story for more on how bacteriophage therapy has been used to save 20 people.