Advantages of Phage Therapy
Bacteriophages already have a history of successful use on a limited scale in various parts of the world. The notion of bacteriophage therapy is not an untried concept but a proven application that has been ignored because of the previous successes of antibiotics. With the emergence of antibiotic resistance, bacteriophages have the potential to become the next biotechnology revolution.
Enumerating some of the other advantages of bacteriophages:
- Bacteriophages are abundantly and easily available in water bodies, sewage systems, hospitals, and other such locales.
- Bacteriophages have been found safe for treating a variety of infections. They are non-toxic and cannot act on anything except the bacteria to which they can attach and into which they can inject their nucleic acid.
- As implied above, bacteriophages are highly specific. Because antibiotics kill all bacteria without specificity, beneficial bacteria (e.g. in the intestinal tract) that perform crucial functions for the human body are also affected and harmful pathogens can then grow more easily. Secondary infections like the Pseudomonas species or Clostridium dificile develop in this way and cause severe diarrhea and colon infections. Bacteriophages will specifically target the harmful bacterium, eliminate it, and leave the beneficial bacteria intact.
- Bacteriophages are non-living entities. Bacteria can cause disease partly because they are living entities that feed on other living organisms (e.g. humans, animals, plants, etc.). Bacteriophages cannot cause disease to humans, animals, or plants; they can only cause harm to bacteria.
- Infections resistant to antibiotics can be treated with bacteriophages. There exist bacteriophages that can specifically target bacteria like Staphylococcus aureus, Enterococcus faecalis, Mycobacterium tuberculosis, and Pseudomonas aeruginosa.
- Bacteriophages are self-replicating. One bacteriophage will co-opt the bacterial cell's biosynthetic machinery to produce potentially hundreds of bacteriophages that will then proceed similarly with other bacteria until all of the bacteria have been eliminated.
- As a result of the bacteriophage's exponential rate of self-replication, usually a small dose is sufficient for curing a bacterial infection. Bacteriophages can penetrate deep into an infection and destroy all of the particular bacterium growing there. Antibiotics, on the other hand, often encounter difficulty penetrating deep bacterial infections and delivery (of the antibiotic) to all of the bacteria then becomes a significant obstacle. This obstacle rarely exists in the case of bacteriophages.
- In addition to being self-replicating, bacteriophages are also self-limiting. When all of the bacteria are infected with bacteriophages, their numbers start to decline and the number of bacteriophages also decreases. Bacteriophages require their specific bacterium in order to exist and, in the absence of that specific bacterium, they are eliminated rapidly.
- Bacteriophages are rapidly acting bactericidal entities. Because bacteriophages kill bacteria, they are referred to as bactericidal. Antibiotics can be bactericidal or bacteriostatic (preventing replication of the bacteria in the hope that the immune system will cure the infection), but bacteriophages will rapidly destroy all of the bacteria they target.
- Unlike antibiotics, bacteriophages evolve with bacteria to combat bacterial resistance. Resistance to bacteriophages appears to be limited so far. However, widespread use will undoubtedly bring resistant bacterial strains. Bacteriophages have a distinct advantage over antibiotics in overcoming resistance because bacteriophages evolve faster than bacteria and those that develop against resistant bacteria can be isolated in days or weeks (at a very modest cost) whereas the development of a new antibiotic takes years (and hundreds of millions of dollars).
- Bacteriophage manufacture involves relatively low cost. The bacteria they infect can be grown in conventional equipment by fermentation (a procedure used in the identification and isolation of the bacteriophage). After the bacteriophages have lysed the bacteria (and thus been identified and isolated), they can be purified by membrane filtration, centrifugation, and other standard methods.
- Bacteriophages, though effective on their own, can be used in combination with antibiotics. Many bacteria are not yet resistant to all antibiotics and some medical applications may benefit from the combined use of bacteriophages and antibiotics.
- Bacteriophage preparations are highly stable. They can be stored for long periods.
- Bacteria are responsible for infections that require amputation and epidemics that kill countless populations; bacteriophages will save lives and limbs.