A World Without Antibiotics? Megan Hardy discusses antibiotic resistance and the importance of antibiotic development
When penicillin, the first antibiotic,
"...the rise of antibiotic resistant strains of bacteria may mean we are entering a ‘postantibiotic era’..."
became widely available in the mid-1940s, modern medicine was revolutionised. Small wounds and childbirth no longer resulted in life-threatening incurable infections. Meningitis, tuberculosis, and chronic bone infections could all be cured. Surgery became safer since pre-operative antibiotics lowered the risk of postsurgical infection, allowing longer and more complex operations to be attempted. Disturbingly, the rise of antibiotic resistant strains of bacteria may mean we are entering a ‘post-antibiotic era’ in which antibiotics become practically useless. While there are currently 700,000 antibiotic resistance related deaths per year, this is predicted to rise to 10 million by 2050. The World Health Organization (WHO) is declaring antibiotic resistance a ‘major global threat’ in which ‘common infections and minor injuries which have been treatable for decades can once again kill’. Pandemics of such superbugs could easily result in global quarantines and lockdowns. Antibiotics Treat Bacterial Infections | Antibiotics are used to treat bacterial infections by interfering with processes that bacteria need to survive and grow such as bacterial cell wall production, protein synthesis, or cell division. On the other hand, viruses are not alive and cannot be killed using antibiotics. This is because viruses cannot reproduce on their own and instead rely on the host cell to make the proteins needed to produce new viruses. This process cannot be inhibited because we are the host — we would be poisoning our own cells. It is our overuse of antibiotics out of convenience which has accelerated the development of antibiotic resistant strains of bacteria. For example, global antibiotic use (average
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A World Without Antibiotics
doses per day) increased by 65% between 2000–2015, with low-middle income countries being the main driving force. Further increases are predicted for the period to 2030 in the scenario that no restrictions are introduced. The Problem Of Antibiotic Resistance | When bacteria face a threat in the form of an antibiotic, it drives evolution for traits that help their survival. Within a population, there is a small chance that some bacteria will harbour a random genetic mutation which allows them to survive exposure to antibiotics. The presence of antibiotics selects for variants containing such a mutation — while the susceptible bacteria are killed, the resistant ones survive, reproduce, and take over the population. This has led to an ongoing evolutionary arms race between our own drug development and bacterial mechanisms to avoid their own death. Research into new antibiotics has slowed down in recent decades, which aggravates the problem. Antibiotics are classified by their chemical structure, cellular mechanism of action, and the species of bacteria they are effective against. During the ‘golden era’ of antibiotics research (1950–1960s), scientists generally overcame problems of antibiotic resistance by developing new antibiotics at a faster rate than bacteria developed resistance. Half of the antibiotics in use today were discovered during this period. In contrast, no new classes of antibiotics have been discovered since the 1980s. The process of discovering genuinely new antibiotics and bringing them to market is challenging and timeconsuming. It can take up to 15 years. Firstly, organisms which produce antibiotic substances are identified. This can be difficult because these substances must also be non‑toxic to humans. Candidate drugs then move
Michaelmas 2020
