Professor Nigel Brown FSB, President of the Society for General Microbiology, is writing an article each month for The Bridge, a local magazine delivered to every home in the villages of Corsley and Chapmanslade in Wiltshire.
Readers will be familiar with going to their GP and expecting a prescription for medicine – quite often an antibiotic. Farmers will be used to vets prescribing antibiotics for their livestock. Since the 1940s antibiotics have been ‘magic bullets’ to treat a whole variety of diseases. Before the commercial production of penicillin during the Second World War, people and animals could die of infections that are now easily cured with antibiotics.
However, there may be a return to the days when some of these diseases are untreatable. Many bacteria which cause infections are becoming resistant to one or more antibiotics. For example, MRSA (methicillin-resistant Staphylococcus aureus), which causes sepsis, is resistant to most antibiotics. Some estimates suggest that by 2050 there will be an extra 10 million deaths due to drug-resistant infections unless we can find new antibiotics.
Why are diseases becoming antibiotic-resistant? Antibiotics are very widely used and can select for resistant bacteria to survive, whereas sensitive bacteria will not. The resistance can transfer to other bacteria. Failing to complete a prescribed course of antibiotics because you feel better can lead to the development of resistance in those few remaining disease-causing bacteria in your body. The use of antibiotics in agriculture has also led to an increase in resistant organisms in the farm environment. UK agriculture used 409 tonnes of antibiotics in 2012. These are often used to treat a whole herd or flock when only a few animals are sick, which is equivalent in human terms to treating a whole street because little Johnny at number 14 has an infection.
Few pharmaceutical companies are looking for antibiotics, as the discovery and development of a new antibiotic is expensive (about £50M), so we are largely reliant on the ones we already have. However, there are some moves to find and develop new antibiotics. These are often found in soil microorganisms, such as fungi and bacteria, and universities are beginning to work with local schoolchildren to identify new antibiotic-producing organisms. This provides hope for the future.
What can we do to ensure that antibiotics are useful in the future?
1. Do not expect your GP to automatically prescribe antibiotics if you have a minor ailment. Coughs and colds are usually caused by viruses, which cannot be treated with antibiotics, and many illnesses you can recover from without any treatment.
2. Always complete the course of antibiotics you have been prescribed.
3. Do not give your prescribed antibiotics to others.
4. On holiday in countries where you can buy them over the counter, do not self-prescribe antibiotics, as you may encourage new resistances in infectious organisms.
The Society of Biology is sponsoring these articles in 2015 through our regional grant scheme, which supports locally focussed activity. This is the first of a series of articles that will focus on the life sciences – health, agriculture and biotechnology