Phages attack the bacteria which cause citrus canker in ABTI-sponsored tests

Phages attack the bacteria which cause citrus canker in ABTI-sponsored tests

Phage Therapy Safety

A "Green" Antibacterial Solution

Reports regarding the looming crisis of antibiotic resistance and its consequences for health care understandably dominates current media coverage. Yet, a secondary but growing concern involves the effects of widespread use of antibiotics in agriculture and veterinary medicine. A 2013 report in Environmental Health Perspectives described how this application of antibiotics contributes to the growth of antibiotic resistance: "Antibiotics . . . are given to farm animals to speed growth and prevent illness. They end up being flushed down drains and leach into soil and groundwater, where they contribute to environmental hot spots of antibiotic resistance."1

Moreover, "approximately 80% of all antibiotics used in the U.S. are fed to farm animals" and "it is estimated that approximately 75 % of all antibiotics given to animals are not fully digested and eventually pass through the body and enter the environment, where they can encounter new bacteria and create additional resistant strains. With huge quantities of manure routinely sprayed onto fields surrounding confined animal feeding operations, antibiotic resistant bacteria can leech into surface and ground water, contaminating drinking wells and endangering the health of people living nearby . . . A considerable amount of pressure is being exerted on the natural microbial environment, including beneficial bacteria, human and animal nutrition and immunity, by the antibiotics provided to humans, animals and plants, as well as the spraying of antibiotics on fruit trees, resulting in dangerous superbugs." 2 A 2012 article in the International Journal of Microbiology further highlighted the potentially toxic effects of copper and other chemicals used to kill bacterial pathogens in agricultural settings, such as citrus groves.3

Accordingly, Western society's over-reliance upon antibiotics and other chemical means of bacterial control has not just directly limited the future effectiveness of such tools; it has exacted its own price upon health and the environment.

Fortunately, phage therapy not only provides an effective alternative to antibiotics for treating and preventing bacterial infections; it also provides an environmentally-friendly means for doing so. Indeed, a 2011 article in the American Society for Microbiology's Microbe Magazine stated that employing phage therapy to "treat bacterial infections in human patients and to improve food safety are two of the safest, 'green' antibacterial applications now available. Phages are highly specific—active against only a specific bacterial species, strain, or subgroup of strains—and cannot infect eukaryotic cells. Moreover, their ubiquity in the environment means we are exposed to them routinely, further certifying their safety." 4 The above-referenced 2012 article from the International Journal of Microbiology noted the "renewed interest" in phage therapy as an alternative antibacterial solution in such settings, "due to the nontoxic nature of phages and their ability to infect antibiotic or heavy metal resistant bacteria."5

Phage Therapy: Verifiably Safe

Naturally, phage therapy's status as a viable alternative to antibiotics does not automatically establish it as a safer - or even safe - alternative. Yet, abundant evidence exists which establishes phage therapy's safety. A comprehensive report on phage therapy by four Western microbiologists characterized phage therapy's safety history as "an enviable track record," stating that despite their presentation regarding "what can go wrong" in phage therapy, "in fact phage therapy as currently practiced rarely if ever results in more than minor side effects." The authors further described one particular oft-cited issue in Western scientific literature - that phages might facilitate gene "transduction," or transfer, between bacteria as "mostly theoretical concerns"1

Another paper outlining the "pros and cons of phage therapy" suggests that the "mostly theoretical concerns" referenced above are not unusual when one takes into account the presence of the same risks in many medicines that have received regulatory approval for human use:

Phages as pharmaceuticals are protein-based, live-biological agents that can potentially interact with the body’s immune system, can actively replicate, and can even evolve during manufacture or use, but are far from unique in these regards. For example, many protein-based pharmaceuticals can stimulate immune systems, antibiotics that lyse bacteria will release bacterial toxins in situ, and live attenuated vaccines both actively replicate and evolve including within the context of infecting body tissues. Protein-based drugs, chemical antibiotics, and whole vaccines have previously been approved for use despite these various properties. It therefore stands to reason that phage-based pharmaceuticals should not be disqualified for possessing similar attributes.

The evidence for the safety of phage therapy follows:

  1. The Natural and "Ubiquitous" Character of Phages Themselves. A 2013 paper entitled "Bacteriophages and their endolysins for control of pathogenic bacteria" stated that "[p]hages are ubiquitous in nature" and that they "can be readily isolated from environmental samples such as soil, sewage and water and their prominence in the environment means that humans are constantly exposed to phages without adverse effect," and that such a result shows "their non toxic nature."2 A report in Microbiology stated that "[w]ithout knowing we constantly consume phages with our fermented food in yogurt, sauerkraut, pickles or salami and that "[f]rom a clinical standpoint, phages appear to be innocuous."3
  2. The Practical Experience of the Georgian and Soviet People. According to the above-referenced 2011 article in the American Society for Microbiology's Microbe Magazine, "[i]n the 90 years during which phages have been used to treat human infections [in Georgia and the other nations which comprised former Soviet Union], their use has led to no reported serious side effects."4 Moreover, the above-referenced article in Microbiology reported that "[o]ral coliphages were given in controlled clinical tests to many thousands of children and adults in the former Soviet Union – apparently without major adverse effects."5
  3. Western Studies Have Unanimously Confirmed the Safety of Phage Therapy.
    • The U.S. Food and Drug Administration (FDA) "conducted a safety review of [phages] in 1973 after phages were found in several vaccines. Agency officials concluded that the vaccines were safe and allowed their continued use." 6.
    • The FDA has approved phage therapy products for food safety purposes, characterizing them as GRAS (“Generally Recognized as Safe”).7
    • In 2008, a "phase I clinical trial evaluating . . . cocktail containing eight phages targeting Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, and the trial included 42 patients with venous leg ulcers. The trial results fully supported the safety of the complex, multiphage preparation in the infected patients."8
    • "[I]n 2009, a double-blind Phase II clinical study showed phages to be safe and effective at treating chronic drug-resistant ear infections."9