Human history has long been intertwined with the environment, whether in the untouched waters of Merri Creek in Melbourne or in the scientific breakthroughs that change the way we approach disease. Today, as we face a growing threat of antimicrobial resistance (AMR), one promising solution might come from a group of organisms that have existed long before humans: bacteriophages.
The Growing Threat of Superbugs
AMR has emerged as a global health crisis that endangers the very foundation of modern medicine. While antibiotics have saved millions of lives since their discovery, their overuse and misuse have led to the rise of “superbugs” — bacteria that have developed resistance to multiple antibiotics. One of the most concerning examples is Klebsiella pneumoniae, a bacteria that resides harmlessly in the human gut but can become dangerous when it spreads outside its usual environment. Klebsiella and other bacteria have evolved to evade the drugs designed to eliminate them, posing a severe risk to those with weakened immune systems and those undergoing treatments like chemotherapy or organ transplants.
In 2023 alone, Australians filled over 22 million prescriptions for antimicrobials, raising concerns among experts about the overuse of antibiotics. As superbugs proliferate, it’s estimated that by 2050, more than 8 million deaths could occur globally due to AMR. With antibiotic development stalled for decades, the search for alternative treatments has become more urgent than ever.
Bacteriophages: The Natural Enemy of Bacteria
Enter bacteriophages, or “phages” — viruses that specifically target bacteria. Bacteriophages have been described as some of the deadliest beings on Earth due to their ability to destroy bacteria. In fact, it is estimated that in Earth’s oceans alone, bacteriophages infect and kill 20-40% of all bacteria every single day. These viruses are found in virtually every environment, from the deep oceans to the rainforests, from sewage to the surface of our skin.
Bacteriophages are relatively simple organisms composed of just proteins and genetic material, yet they are highly specialized predators of bacteria. Their mechanism of infection is fascinating: a phage attaches to the surface of a bacterium using its “legs” and injects its genetic material into the bacterial cell. Once inside, the bacterium is turned into a factory that churns out thousands of new phage particles, which then burst open the bacterial cell, releasing the newly created phages to continue the cycle.
This process of bacteriophage-mediated destruction of bacteria has intrigued scientists for decades, but the potential for phage therapy has gained significant attention in recent years due to the escalating AMR crisis.
Phage Therapy: A Potential Solution to Superbugs?
In the quest for alternatives to traditional antibiotics, bacteriophage therapy has emerged as a promising candidate. Phages are highly specific to the bacteria they infect, meaning they don’t harm human cells or the beneficial microbes that reside in our bodies. Unlike antibiotics, which often disrupt the entire microbiome, phages selectively target harmful bacteria, offering a potentially safer and more targeted treatment approach.
The discovery of phages in unexpected places, like Merri Creek in Melbourne, highlights their ubiquity and promise. Trevor Lithgow, a biochemist at Monash University, and his team isolated a phage from this waterway that showed remarkable ability to kill Klebsiella pneumoniae, one of the major threats among drug-resistant bacteria. This particular phage was named “Merri-merri-uth nyilam marra-natj” by the traditional Wurundjeri owners of the land, meaning “dangerous Merri lurker.” Similar discoveries of potent phages have been made around the world, including in wastewater in Bangkok and the Sea of South Korea.
Phages can also penetrate bacterial biofilms, a slimy protective barrier that many bacteria form to shield themselves from antibiotics. This makes them particularly effective against infections that have become resistant to traditional treatments, such as those caused by Staphylococcus aureus and Pseudomonas aeruginosa.
The Challenges of Phage Therapy
Despite the promising potential of phage therapy, there are several challenges to its widespread use. One of the primary obstacles is the lack of standardized testing and regulatory frameworks. While phage therapy has been used with some success in countries like Georgia and Russia, it has yet to be fully approved in places like the United States, Europe, and Australia. In these regions, phages are still considered experimental therapies and are typically only available to patients through special access programs.
Additionally, the development of phage therapy requires a significant amount of research to determine which phages are effective against specific bacteria, how they interact with the human body, and how they should be administered. This has led to the rise of clinical trials such as the “Stamp study” in Australia, which aims to standardize phage therapy and monitor how phages interact with patients’ immune systems and microbiomes.
One of the major advantages of phage therapy over antibiotics is the potential for phages to adapt to bacterial resistance. Bacteria evolve rapidly, but phages can evolve alongside them, making it possible for phages to overcome the defense mechanisms that bacteria develop. Moreover, phages have been shown to re-sensitize bacteria to antibiotics, offering a dual approach that could potentially rejuvenate the efficacy of existing antibiotics.
Real-Life Impact: Phage Therapy in Action
The potential of phage therapy was dramatically illustrated in 2015 when Tom Patterson, the husband of epidemiologist Steffanie Strathdee, contracted a multidrug-resistant strain of Acinetobacter baumannii while traveling in Egypt. With all conventional antibiotics failing, Patterson’s medical team turned to phage therapy as a last resort. The treatment was successful, marking a watershed moment for phage therapy in the U.S. This case, among others, has brought renewed attention to the potential of phages as a tool in the fight against superbugs.
Looking to the Future: Can Phages Save Us?
As AMR continues to escalate, the urgency for new treatments has never been greater. Phage therapy represents one of the most promising avenues for combating superbugs, with researchers around the world working tirelessly to harness the power of these natural bacteria-killers. The future of phage therapy looks bright, but much work remains to be done before it can become a mainstream treatment option.
For now, the global scientific community is focused on overcoming regulatory hurdles, standardizing treatment protocols, and expanding the knowledge of how phages can be used safely and effectively in clinical settings. If successful, bacteriophage therapy could become a key weapon in the fight against AMR, offering a new hope for patients suffering from infections that have eluded traditional antibiotics for decades.
As scientists continue to explore the potential of bacteriophages, they offer a glimmer of hope in an age where superbugs are on the rise. Whether from the waters of Merri Creek or deep within the Mariana Trench, bacteriophages may hold the key to saving countless lives in the battle against antimicrobial resistance.
