At some point, most of us will have taken an antibiotic – a drug course that typically involves strict abstinence from alcohol and tedious weeks of waiting for the prescription to finish. While they may certainly be effective, doctors and governments are increasingly cautious when it comes to prescribing these drugs. Ultimately, this is to combat a global, urgent crisis which is on the rise: antimicrobial resistance (AMR).
The World Health Organisation (WHO) defines AMR as occurring when bacteria or other pathogens no longer respond to antimicrobial drugs. When AMR occurs, symptoms inflicted cannot be treated effectively, leading to poorer outcomes for those infected.
Antibiotics, targeting bacteria, are just one of the sub-classes of antimicrobials. They are incredibly useful in preventing and treating infections. However, this has led to overuse in humans, animals and plants, which has been a critical facilitator of AMR.
When antimicrobials are used, they kill most of the pathogens they target. However, microorganisms have very fast evolution timescales: they can mutate and evolve frequently. By acquiring mutations, pathogens can become resistant to drugs, developing into ‘stronger’, more resistant strains that can no longer be destroyed. Using more antimicrobials increases the probability of such events occurring.
Another common mistake is not completing the full course of the medicine. Doing so means that it is less efficient: not all the pathogens might have been killed, and the ones remaining will be the most resistant. Eventually, they might remain in the organism and proliferate beyond control. If these strains spread, a new antimicrobial must be developed to fend off the ‘super’ strain.
However, since the 1980s, there have been no new classes of antibiotics discovered, although variations of drug classes have been developed. Large pharmaceutical companies are abandoning research, with smaller pharmaceutical companies accounting for 90 per cent of antibiotic developments. Estimates suggest that developing antimicrobial drugs costs over $1bn and the process takes 10 to 15 years to reach patients.
A recent breakthrough for antibiotic treatment is Gepotidacin, used to treat female urinary tract infections. It is the first antibiotic developed for this use in over 30 years.
There are multiple mechanisms by which antimicrobials induce therapeutic effect, but interestingly, gepotidacin prevents bacterial DNA replication by targeting two enzymes. This dual targeting means that for bacteria to become resistant, it must acquire mutations in both target genes instead of one, making resistance less likely. This makes gepotidacin effective against resistant strains such as E. coli. Although there have been no antimicrobials found to evade resistance, this breakthrough drug shows promise in finding ways to reduce further resistance development.
While researchers do their best to address the situation, public health interventions such as vaccine rollouts can be effective ways to reduce antimicrobial needs. The WHO estimates that optimal vaccine use could prevent 106,000 AMR-related deaths annually and reduce antibiotic use by billions of doses.
Generally, the UK Government recommends a few powerful actions that all of us can take. The first is to avoid taking antibiotics for minor illnesses, particularly colds and flus, as these are often caused by viruses, which would need antivirals. Secondly, you should never ‘save’ antibiotics for later use, as resistance could develop, and the antibiotics will no longer work. Prescribed antibiotics should be taken exactly as directed by your GP, nurse or pharmacist.
Although simple, the implementation of these changes by the general population could have a significant impact in reducing the projected 39 million AMR-related deaths by 2050. Collectively, we must spread awareness and play our parts by reducing consumption and always finishing prescriptions — even when the symptoms have vanished!
Photo by Harrison Chang on Unsplash