Future of Antibiotic Resistance: Encouraging or Not? I Varjitha

In 2019, approximately 1.2 million people died from antibiotic-resistant bacterial infections. [1] The main cause for antibiotic resistance is when bacteria itself develops the ability to overpower the drugs that are meant to kill them. [2] This means that the bacteria will be able to grow continuously and cause more harm to the body’s immune system. Despite the fact that the mutation which occurs in bacteria that enables it to be resistant, disappears over time, it does not take away the fact that numerous lives are lost every year due to antibiotic resistance. [3] In fact, it is estimated that by 2050, antibiotic resistance will cause around 10 million deaths a year. [4] What makes the situation much worse

is that the resistance in bacteria has been found in common infections such as tuberculosis. This puts doctors in a difficult position, where it becomes nearly impossible to treat the infections.

However, in a world where technology is developing very quickly, scientists have looked into alternatives to antibiotics and as bizarre as it may sound (especially due to the pandemic we are living in), the substitute is in fact- viruses. Viruses that are known as bacteriophages, or phages, have the ability to infect bacteria. The study of phage therapy, which involved using phages to treat bacterial infections, was initially discovered in 1919; however, due to the discovery of antibiotics in 1928, the research into phage therapy slowed down. [5] Regardless of this, bacteriophages were believed to be what we need to solve the antibiotic resistance crisis.

Firstly, a phage consists of a head and a tail. The head contains viral nucleic acid, which is made up of lots of nucleotide monomers. [6] In addition to this, the way they attack bacteria is in fact quite similar to antibiotics. The phage attaches to the bacteria and injects the nucleic acid into the cell, then the virus multiplies and consequently this causes the bacterial cell to burst, hence killing it. [5] Due to the nature of bacteria, they are able to mutate and change easily, which protects them from antibiotics and phages. Equally, viruses are also able to evolve, which means they can reproduce various phages, to attack the evolving bacteria.

It is obvious that bacteriophages are not currently being prescribed by doctors to treat bacterial infections. Despite the fact that phages would reduce the extent to which antibiotic resistance happens, many other problems arise when looking at the practicality of them. One problem is that phages have a limited host range. [5] A host range is the number of species the phage can kill. [7] This means that only one specific bacteria is killed by each phage. On the other hand, antibiotics have the ability to destroy similar bacteria in addition to the one that is causing the infection; therefore having a higher host range. Furthermore, the concentration of phages also has a large impact on its ability to kill bacteria. [8] If the concentration is too low, then the bacteria will not be killed and the fact that it is difficult to closely measure the concentration, puts at risk the ability to use phages.

So, where does that leave us now? It is the common assumption that preventing antibiotic resistance purely relies on using antibiotics as directed and when it is necessary. However, there is much more to it. Regularly washing hands and preparing food hygienically, also has a large impact on the extent to which antibiotic resistance happens. [9] As for the future of bacteriophages, although there is hope, we are just not here yet. [10]

References

Image:https://pharmaceutical-journal.com/article/feature/beyond-antibiotics-harnessing-bacterias-natural-predators

[1] Oxford University. 2022. An estimated 1.2 million people died in 2019 from antibiotic-resistant bacterial infections, University of Oxford. [online] Available at: <https://www.ox.ac.uk/news/2022-01-20-estimated-12-million-people-died-2019-antibiotic-resistant-bacterial-infections> [Accessed 10 February 2022].

[2] Centers for Disease Control and Prevention. 2022. What Exactly is Antibiotic Resistance?. Available at: <https://www.cdc.gov/drugresistance/about.html> [Accessed 10 February 2022].

[3] Science Daily. 2017. Managing antibiotics not enough to reverse resistance. Available at: <https://www.sciencedaily.com/releases/2017/11/171122093052.htm> [Accessed 10 February 2022].

[4] Mohammed, M. and Millard, A. 2020. Antibiotic resistance: scientists are reengineering viruses t

o cure bacterial infections. The Conversation. Available at: <https://theconversation.com/antibiotic-resistance-scientists-are-reengineering-viruses-to-cure-bacterial-infections-127283> [Accessed 10 February 2022].

[5] Gunathilake, D. 2019. Phages vs. Antibiotics. Let's Talk Science. Available at: <https://letstalkscience.ca/educational-resources/stem-in-context/phages-vs-antibiotics> [Accessed 10 February 2022].

[6] Roberts, R. Nucleic Acid Definition, Function, Structure, & Types. Encyclopedia Britannica. Available at: <https://www.britannica.com/science/nucleic-acid> [Accessed 10 February 2022].

[7] Hull, R. 2014. Host Range- Plant Viruses and Their Classification.Science Direct. Available at: <https://www.sciencedirect.com/topics/medicine-and-dentistry/host-range> [Accessed 10 February 2022].

[8] Srisuknimit, V., 2018. Fighting

Fire with Fire: Killing bacteria with virus. Science in the News. Available at: <https://sitn.hms.harvard.edu/flash/2018/bacteriophage-solution-antibiotics-problem> [Accessed 10 February 2022].

[9] World Health Organisation. 2020. Antibiotic resistance. Available at: <https://www.who.int/news-room/fact-sheets/detail/antibiotic-resistance> [Accessed 10 February 2022].

[10] Iftikhar, MD, N. 2019. Phage Therapy: How It Works, Pros and Cons, Availability, and More. Healthline. Available at: <https://www.healthline.com/health/phage-therapy> Accessed 10 February 2022].

Romero-Calle, D., Guimarães Benevides, R., Goes-Neto, A. and Billington, C., 2019. Bacteriophages as Alternatives to Antibiotics in Clinical Care. MDPI, 8(3), p.138.