The COVID-19 coronavirus pandemic has already claimed the lives of over 500,000 people (as of June 28, 2020), and developing methods for preventing and treating COVID-19 is currently the world's number one priority. The journal Phage has published a review* in which author Marcin W. Wojewodzic explores the potential of using bacteriophages to combat the SARS-CoV-2 coronavirus, primarily to reduce mortality in patients with acute respiratory syndrome.

The review's author notes that one of the causes of COVID-19-related mortality is the inconsistency between innate (nonspecific) and adaptive (specific) immunity, resulting in a failure to produce specific antibodies against SARS-CoV-2 in a timely manner. Further research is needed, but the high mortality rate among elderly people with COVID-19 could potentially be linked to secondary bacterial respiratory infections associated with high viral loads.

If bacterial growth due to delayed antibody synthesis against the coronavirus contributes to increased mortality, then suppressing bacteria in the respiratory system can give the body time to develop an adequate adaptive immune response (the synthesis of specific antibodies). Conversely, administering synthetic antibodies against SARS-CoV-2 can support the body's fight against the virus. Reducing bacterial growth and viral binding by synthetic antibodies should reduce the release of proinflammatory substances in the lungs, which are one of the indirect factors contributing to COVID-19 death.

Read also: Scientists are developing a COVID-19 vaccine based on a bacteriophage.

Marcin W. Wojewodzic believes that while antibiotics may be the solution to the first problem, there are other agents that can serve as an alternative to antibiotics or be used independently – bacteriophages. More than 70% of patients hospitalized with COVID-19 receive antibiotics. This threatens to increase the number of antibiotic-resistant strains and create problems with the choice of antimicrobial agents for the treatment of many dangerous diseases. A key advantage of bacteriophages is the low likelihood of resistance developing in target bacteria and the relative ease of updating phage preparations in cases where resistance does develop. Furthermore, bacteriophages, unlike antibiotics, ensure the preservation of the human microbiota, which is crucial for patient health. In the case of bacterial respiratory infections, bacteriophages against the most common pathogens causing respiratory complications can be administered as an aerosol into the respiratory tract.

Regarding the second problem—reducing the viral load—bacteriophages may also be useful. Synthetic antibodies can be produced using phage display technology . These synthetic antibodies will help the patient "buy time" to create their own antibodies against SARS-CoV-2 and reduce the risk of an excessive immune response, which could be destructive.

* Wojewodzic MW. Bacteriophages Could Be a Potential Game Changer in the Trajectory of Coronavirus Disease (COVID-19). PHAGE, 2020, 1 (2): 60-65. http://doi.org/10.1089/phage.2020.0014