Why are superbugs a threat?

The new climate change

When Alexander Fleming discovered penicillin in 1928, medicine was changed forever. Now bacterial infections that would once have been deadly were easily treatable with antibiotics. But over time, strains of bacteria resistant to antibiotics have evolved – superbugs. Superbugs have been called ‘as big a global threat as climate change and warfare’. But why do they exist? And how can we stop them?

Over time, bacteria adapt to the drugs used to kill them and evolve to become resistant to them. In a large population of bacteria, some will not be affected by an antibiotic due to natural resistance or chance mutation. When a patient is given antibiotics, these bacteria therefore survive and can then reproduce, creating a larger population that is now immune to that antibiotic. This kind of bacteria is becoming more and more common today.

Historically, superbugs have been confined to hospitals and care homes but are now travelling in the general population. The World Health Organisation has received reports of 500,000 people across 22 countries with antibiotic-resistant infections, and it is estimated that superbug infections kill around 23,000 people in America alone each year, a figure comparable to the 38,000 who die in car accidents. The number of antibiotics a superbug is resistant to depends on the bacteria, but in 2016, a type of bacteria resistant to all known antibiotics was detected in the US for the first time.

Superbugs are becoming more and more common due to several factors. One is our overuse of antibiotics due to misdiagnosis or over-prescription. There is also widespread use of antibiotics in farming. For example, in the US more than 70% of antibiotic use is in animal agriculture, often unnecessarily, to prevent disease or increase growth in animals. Although this is useful in farming, it has meant that many superbugs have evolved in livestock, which could travel to humans when the animals are eaten, especially if they are not prepared properly.

So how can we deal with superbugs? One strategy is to reduce antibiotic use by improving diagnostic tests to detect if an infection really requires the use of antibiotics for treatment and changing farming practices where antibiotics are not necessary. Research is also being done to try and create new antibiotics. This is very expensive, but we have only examined about 1% of chemicals from the world’s bacteria, so there is a chance that more antibiotics could be out there. We could also try and use viruses called bacteriophages to infect and kill bacteria, which has shown success in Russia, although it hasn’t passed safety rules in the West yet.

Ruby V