The COVID-19 pandemic has revealed not only humanity's vulnerability to viruses but also the true scale of another, no less dangerous epidemic: antibiotic resistance . Every day, thousands of patients around the world receive treatment that is ineffective: superbugs are becoming increasingly sophisticated in their survival strategies. However, on this invisible front, we have long had allies: bacteriophages.

A Quiet Breakthrough in Science: What Are Phages Hiding?

Bacteriophages, or simply phages, are naturally occurring viruses that destroy only bacteria. Their action is astonishingly precise: they penetrate the bacterial cell, replicate within it, and destroy it from the inside. What's most interesting is that phages have coexisted with bacteria for millions of years, refining their attack mechanisms. This process is evolutionarily perfect.

Few people know, but bacteriophages are not just a treatment. They are already used as a biocontrol tool in medicine, agriculture, and the food industry. For example, in EU countries, phages are used to treat meat and vegetables to kill harmful bacteria such as Listeria , Salmonella , and E. coli . This is not a treatment in the classic sense, but rather a preventative measure against food-based infections.

The Immune System, the Microbiome, and Phages: A Delicate Interplay

When using antibiotics, we often kill not only the pathogen but also all friendly microflora. This paves the way for fungal infections, weakened immunity, and metabolic disorders. Phage therapy maintains the microbiome's balance because it acts in a targeted manner. Furthermore, some studies suggest that phages may have an immunomodulatory effect, harming and potentially enhancing the immune response.

Phages are also capable of penetrating biofilms —bacterial defense structures that are a real problem in chronic infections. These viruses "disassemble" their structure and destroy the bacteria. This aspect is particularly valuable in cases of implant infections, osteomyelitis, or respiratory damage in cystic fibrosis.

Challenges and new horizons of phage therapy

Phages aren't a cure-all. They require thorough diagnostics: for effective treatment, it's necessary to know exactly which bacterial strain is causing the infection, which isn't always possible in time-sensitive settings or in medical facilities without the necessary equipment. However, modern technologies can expedite diagnostics to just a few hours.

Experiments are also currently underway with synthetic phages, genetically modified to enhance their effectiveness. For example, they are being enhanced with genes that destroy bacterial toxins or accelerate bacterial death. This paves the way for the creation of next-generation phages.

Not just treatment: bacteriophages are used in transplantology, oncology, and even psychiatry. Phages are already being studied as a means of reducing infectious complications after transplants, when the patient's immune system is weakened. Clinical trials are underway in France and Canada, where these viruses are administered to patients prophylactically after organ transplants.

There are other unexpected directions, too. For example, Cambridge researchers are studying the role of bacteriophages in regulating the gut-brain axis —the connection between the gut and the brain. Theoretically, by influencing the gut microbiota, phages could indirectly influence the symptoms of depression, anxiety disorders, and even autism. This is no longer just a treatment for infection—it's a biotechnological revolution that is changing our understanding of health.

Fagobank: The Weapons of the Future Today

Several European countries already have phage banks—biotheques—that store thousands of virus samples against various bacterial species. When a patient needs urgent care, the right bacteriophage can be found within hours. In the future, such banks could serve as global hubs for rapid response to epidemics or bioterrorist attacks.

Ukraine has the potential to become a leading country in this field. We have strong biotechnology schools, a tradition of using phages, and a need for affordable and effective solutions to treat post-war infections. Phages are not science fiction, but a real alternative that is becoming increasingly accessible. Their strength lies in their precision, naturalness, and evolutionary wisdom. While antibiotics are losing their potency, bacteriophages promise a new era of medicine—personalized, environmentally friendly, and effective.