How Viruses Could Aid Our Race Against Antibiotic Resistance
Photo by Fusion Medical Animation on Unsplash
In September 1928, Scottish microbiologist Alexander Fleming made a miraculous discovery. Fleming was researching Staphylococcus bacteria at the St. Mary's Hospital in London but had paused his research to take a short vacation. Unbeknownst to him, he had mistakenly left a messy stack of bacteria-filled petri dishes out in the open. Upon returning to his lab, he noticed something strange: one of the dishes he had left exposed had grown mold upon it. While the presence of the mold was not especially surprising, Fleming was shocked to realize that the bacteria surrounding the mold had been killed. Fleming soon identified the mold as a strain of Penicillium notatum and isolated the bacteria-killing substance it produced– penicillin, the first antibiotic. Eventually, in the 1940s, Austrian pathologist Howard Florey, and British biochemist, Ernst Chain, were able to suitably refine and mass-produce penicillin for proper medicinal usage. In the early 20th century, infectious diseases were the leading cause of death. Thanks to Fleming's accidental discovery of penicillin, by 1950, the death rate from infectious disease had fallen by nearly 90%.
Since the discovery of penicillin, more than 150 antibiotics have been found. Over the past century, we began to use antibiotics to treat the most severe diseases and the most mundane infections alike. In fact, our use of antibiotics has become so commonplace that we've created a new crisis– bacteria have begun to fight back. As all living organisms do, bacteria evolve. If bacteria are continuously exposed to an antibiotic, the population of bacteria may eventually adapt to the antibiotic and develop resistance, creating what's known as a superbug. Misuse and overuse of antibiotics, therefore, allow for resistance to develop more easily. This presents a pressing issue: we rely heavily on antibiotics to keep bacteria at bay, yet the more we use antibiotics the less effective they get. Antibiotic resistance has quickly become a very relevant problem, contributing to millions of deaths per year. Researchers and scientists are racing to develop alternative therapies and novel antibiotics. Surprisingly, the solution to our antibiotic crisis may lie in an unlikely ally– viruses.
In November 2015, psychiatrist Tom Patterson was infected with a rare bacteria called Acinetobacter baumannii while on vacation with his wife in Egypt. Patterson was rushed to a hospital, where he went into a coma. Notorious for causing hospital-acquired infections, Acinetobacter baumannii was highly resistant to all available antibiotics, leaving doctors helpless against the infection. As a last resort, in March 2016, doctors administered a cocktail of bacteriophages– viruses that specifically attack bacteria– alongside a dosage of antibiotics. That day, Patterson became the first person in the U.S. to receive intravenous phage therapy for a systemic multidrug-resistant infection. 3 days later, Patterson woke up from his coma. After a few months, he was almost entirely cured. The success of his treatment was due to a two-pronged approach. First, bacteriophages naturally target specific bacteria species without harming human cells. This makes them effective at killing bacteria because, unlike antibiotics, they are capable of evolving alongside bacteria. Therefore, they can adapt to defenses that the bacteria develop against them. Secondly, in some cases, when bacteriophages and antibiotics are used in tangent, the bacteria must sacrifice resistance to one in order to defend against the other, in a phenomenon known as collateral sensitivity. By combining antibiotics with phage therapy, we may be able to effectively fight against antibiotic-resistant infectious bacteria.
While phage therapy has proven to be a promising tool in the race against antibiotic resistance, significant amounts of further research and validation is required before it can be used clinically. A large concern with phage therapy stems from the reason why bacteriophages are useful in the first place: they can evolve, making them unpredictable. Some studies prove that bacteriophages can remain in the body long after killing the harmful bacteria they originally targeted, indicating that utilizing phage therapy may have a negative impact on human health. If we overcome these challenges, however, phage therapy may well usher in a modern medical revolution.
