Bacteriophage therapy
innovative antibiotics are scarce due to the low economic viability, phages may be one of the only viable options left to modern medicine.
Disadvantages persist, however, as the superiorities of phages outlined above can also be a double- edged sword. The time-consuming procedure entailed by the specificity of phages can take a relatively long time for the correct active phages to be prepared (or engineered in advance) and become available for administration. This period of delay may result in dire consequences if the patient is in urgent need of treatment. This process usually involves a group of phage researchers in order to be adequately performed, thus ensuing additional costs than routine antibiotic therapy, a point to which I will return later. Phages’ nature of amplifying at the site of infection makes it incredibly difficult for doctors to determine the exact appropriate dosage of phages needed in each case as what they normally do with antibiotics. Moreover, it is exceedingly difficult for the regulators to be fully convinced of their therapeutic safety and stability, given phages’ dynamic and non -uniform genetic variability. Therefore, a more innovative regulatory model (even several models) that effectively responds to the unique biological and pharmacological characteristics of phages should be considered. This issue will be further discussed later. It is noteworthy that phages have a powerful synergistic potential when administered with antibiotics, and a reduced acquisition of antibiotic resistance in phage-resistant bacteria is also observed. In the experiment conducted by Chaudhry et al. (2017), several combinations of phages and bactericidal antibiotics were applied as an attempt to target and kill in vitro biofilm populations of Pseudomonas aeruginosa PA14. Separately by themselves, phages and drugs commonly had only relatively limited killing effects, whereas certain phage-drug combinations lead to significantly reduced bacterial densities, indicating a stronger synergistic killing power. Traditional phage therapy against bacterial infections is currently applied on compassionate grounds to patients with chronic, persistent antibiotic-resistant infections. In 1997, 41-year-old Canadian jazz musician Alfred Gertler experienced a catastrophic climbing accident in Costa Rica while working on a cruise ship and unfortunately contracted a severe Staphylococcus infection in his ankle. Soon, the Staphylococci rapidly colonized his bone, which was unreachable by traditional antibiotics due to the insufficient blood supply around the bone. After a prolonged time of continuous antibiotic treatment, the bacteria acquired AMR and became an unbearable threat to Gertler’s life. His orthopaedist in Toronto explicitly told him, ‘If you don’t die, then your foot will . ’ Af ter spending more than three years almost completely immobilized in bed, Gertler eventually decided to have his infection treated at the Eliava Institute in Georgia, where phage researchers successfully identified and isolated the active phages against the drug-resistant Staphylococci. A phage cocktail was intravenously administered into his ankle, and after three days, the presence of the Staphylococci became unobservable. After two more weeks, he was discharged and returned with content to his longed-for normal life. 41 In late 2015, Tom Patterson, a psychology professor from the University of California, San Diego, contracted antibiotic-resistant A. baumannii when he was on a holiday trip with his wife to Egypt. The initial onset of his infection was mild vomiting, and he was thus first mistakenly diagnosed with food poisoning until officially identified as an A. baumannii infection in Frankfurt, Germany. 42
His condition deteriorated at a rapid rate, and he fell into a coma. Patterson was tested for sensitivity to antibiotics, and not a single antibiotic was significantly effective. At that time, the average mortality
41 Häusler 2008. 42 Strathdee 2017.
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