What are bacteriophages and why are they better than antibiotics

What are bacteriophages

Bacteriophages Bacteriophages: A Therapy Concept against Multi-Drug - Resistant Bacteria are viruses that kill bacteria but do not harm other living organisms.

The root "-phagos-" translated from ancient Greek means "devour". Actually, this is how these specific viruses work. They penetrate the bacteria, "infect" it and replace the bacterial genome with their own. Thus, the microbe loses its ability to multiply. Instead, he begins to produce more and more new bacteriophages, which are slowly exterminating the entire colony of bacteria.

Sometimes bacteriophages are simply called phages, and their use in the form of tablets or injections to fight pathogenic bacteria is phage therapy, or phage therapy.

Just like antibiotics, bacteriophages are antibacterial agents. In general, they do the same job - they kill bacteria, but they do it in different ways.

How bacteriophages differ from antibiotics

Antibiotics contain chemicals that kill bacteria or prevent them from multiplying. This is a plus.

Now the cons. First, each antibiotic is effective against only one or several types of pathogenic microorganisms. Secondly, bacteria, since they are alive, are able to adapt to the action of the drug and eventually lose their sensitivity to it. That is, an unpleasant situation develops: you are taking an antibiotic, but you cannot cure the bacterial infection. This resistance of microbes to antibacterial agents is called antibiotic resistance.

Each type of bacteriophage (and there are millions of them) is also effective Bacteriophages: A Therapy Concept against Multi-Drug - Resistant Bacteria only against “its own” type of bacteria. But a process similar to antibiotic resistance does not arise when they interact with microbes, because bacteriophages are viruses and they can change Phage Therapy in the Postantibiotic Era. When the bacterium adapts and stops allowing the virus to reach the genome, the phage can find a new "key" for it - and achieve its goal.

Why antibiotics are known, but bacteriophages are not very well

This is an example of historical injustice.

In general, phage therapy appeared even earlier than antibiotic treatment. Back at the end of the 19th century, a number of scientists, including the Russian microbiologist Nikolai Gamaleya, whose name bears the National Research Center for Epidemiology and Microbiology, discovered Bacteriophage Therapy that certain substances contained, for example, in river water, exhibit pronounced antimicrobial activity.

In 1917, a microbiologist from the Paris-based Pasteur Institute Felix d'Hérelle told the world that these substances turned out to be specific viruses - the very same bacteriophages. The scientist found in The epic of phage therapy that phages always appeared in the stool of patients with dysentery before the patients got better.

D'Herelle placed a sample of feces containing dysentery bacillus in a Petri dish. He added there a sample taken from a recovering patient, and after a few days found that the dysentery bacteria had disappeared. "Dissolved like sugar in water!" - the researcher described his observations to The epic of phage therapy.

Based on the detected bacteriophages, the scientist made Phage as an antimicrobial agent: d'Herelle's heretical theories and their role in the decline of phage prophylaxis in the West injections and suspensions, which he began to administer to patients with dysentery. Already in the 1920s, phage therapy was used to successfully treat not only this disease, but also typhoid fever, cholera, staphylococcal infections of the skin and bones, and sepsis.

Bacteriophages conquered the world as an antibacterial agent. They were used in the largest hospitals in Europe and the USA, and in the USSR, thanks to d'Herelle, a laboratory for the production of such drugs was created by The strange history of phage therapy. But in the 1940s, the world "phageomania" stopped.

One of the reasons was the development of science. In particular, the requirements for the quality of scientific works have sharply increased. And d'Herelle and his followers were careless about this: they did not conduct the research entirely correctly, made mistakes in the description of biological and physiological processes.

In addition, at the same time, the first antibiotic based on penicillin was created. The authors of the drug approached the research more scrupulously. As a result, antibiotics have become a recognized method of antibiotic therapy in Europe and the United States, and phage viruses have been forgotten. Studies of "bacteria eaters" continued only in the USSR.

Why are they talking about bacteriophages right now?

Because antibiotics are losing ground. People are accustomed to them, perceive them as safe medicines that can be taken "for prevention." As a result, more and more dangerous bacteria become resistant to antibiotics and stop responding to them.

For several years now, WHO has named antibiotic resistance as one of the most serious threats to human health.

People may soon find that the usual and reliable drugs have become a dummy. There is a risk that even sore throat or bacterial otitis media will again become fatal infections for which there is no cure.

Theoretically, nothing prevents the creation of new antibiotics, to which bacteria have not yet developed resistance. But such developments take years or even decades.

In such conditions, bacteriophages can become what will help the world overcome a large-scale medical crisis. Virus-based drugs can be created much faster and cheaper. Bacteriophages: the medicine of the future than antibiotics. But the main thing is that bacteriophages are able to change following the target bacterium, which means that such drugs will remain effective.

Can bacteriophages completely replace antibiotics?

No, at least not yet. There are several reasons for this.

Bacteriophages are still not well understood

Bacteriophages: A Therapy Concept against Multi-Drug - Resistant Bacteria is still lacking in authoritative large-scale studies that would confirm the efficacy and safety of phage therapy.

In addition, regulatory authorities in different countries are suspicious of the idea of using viruses for treatment. For example, the US Food and Drug Administration (FDA) approved the FDA Approves Bacteriophage Trial, the first clinical trial of an intravenous bacteriophage, only in February 2019.

One day, the certification and licensing process for phage products will probably be simplified. But this moment has not come yet.

Bacteriophages have too narrow a specialization

A single broad spectrum antibiotic can treat multiple bacterial infections. But bacteriophages are snipers: they purposefully destroy only one type of bacteria. Therefore, for each causative agent of the disease, you need to select its own phage.

Not only that, the bacterial components of diseases differ from region to region, and sometimes even from person to person. As a result, in order to cure the same sore throat in 10 people in Russia and, for example, in Italy, 10 different bacteriophages or a complex cocktail of them may be required.

Today, the versatility and effectiveness of working antibiotics is somewhat higher.

Bacteriophages seem to work best in combination with antibiotics

Experiments on cell and animal cultures show Phage ‑ Antibiotic Synergy via Delayed Lysis that, if bacteriophages and antibiotics are used simultaneously, their total effect exceeds the sum of the effects of each drug separately. This mutual reinforcement is called synergy.

So far, there is no convincing evidence that synergy will manifest itself in humans. But scientists are optimistic about Stronger together? Perspectives on phage ‑ antibiotic synergy in clinical applications of phage therapy, that this is inevitable.

In one study, Phage treatment of an aortic graft infected with Pseudomonas aeruginosa, the bacteriophage OMKO1, combined with the antibiotic ceftazidime, was able to relieve a patient of superinfection, which had been unsuccessfully treated with traditional antibiotics for several years.

So bacteriophages will most likely not replace antibiotics. These drugs will complement each other to make the treatment of bacterial diseases faster and more effective.