Something that has really struck me this year is learning about antibiotic resistance. It is such a widespread issue that affects every single one of us.
So, let’s start at the beginning…
What are antibiotics?
Antibiotics are widely used in the western world and most of us will have used antibiotics at some point in our lives. Antibiotics are great for many reasons, they are both convenient and effective. They prevent and treat bacterial infections by killing bacteria and can be taken in 5-7 day courses . Before the times where antibiotics were widely used, people could die from something as small as a cut getting a bacterial infection. So, if they’re so easy to use and great at their job then what’s the problem?
What is antibiotic resistance?
Antibiotic resistance is the growing problem of bacteria becoming resistant to antibiotics. This happens because bacteria generally have a fast generation time, meaning the time it takes to asexually reproduce another generation is a short amount of time. Due to the fast generation time and large amount of offspring, mutations happen often. Sometimes the mutations may make the bacteria resistant to the antibiotics and therefore they will survive and continue to reproduce making a whole lot of antibiotic resistant bacteria. These bacteria then can’t be killed by such antibiotics.
This is a massive problem because antibiotics are vital in treating infectious diseases such as tuberculosis, pneumonia and blood poisoning . We need antibiotics.
Antibiotic resistance is a widespread problem affecting us all but what can we do about it?
The overuse and misuse of antibiotics
One of the reasons antibiotic resistance is on the rise is the overuse of antibiotics. Antibiotics kill bacteria and therefore should only be used to treat bacterial infections. In 2015 the World Health Organisation estimated that in half of antibiotic prescriptions the conditions are caused by viruses . They do not cure viruses such as colds and the flu . When people go to the doctor they often expect antibiotics even when they don’t need them. This is a problem because it exposes bacteria to antibiotics and therefore more bacteria become resistant.
There are things we can all do to prevent this such as not requesting or taking antibiotics when you do not need them, for example for a virus [2, 3]. Also make sure you finish the full course of antibiotics as otherwise some bacteria may survive and return.
Antibiotics in Agriculture
Antibiotics are commonly used in agriculture. They have many uses such as treating, controlling and preventing diseases . They may also be used to promote animal growth . There has been some evidence that antibiotic use in agriculture can impact antibiotic resistance in humans . The use in animal growth is not necessary to the health of the animal and therefore is not necessary and may be contributing to antibiotic resistance. It is important for avoiding antibiotic resistance that we stop this from happening.
In New Zealand, so far there has been no evidence that in-feed antibiotics cause antibiotic resistance in humans . However, there has not been much research. The Ministry for Primary Industries has said that most antibiotics in New Zealand agriculture can only be used to treat an individual showing symptoms or an individual in a group with others showing symptoms . However, this ruling does not cover all the antibiotics and there is little information on exactly what is being done. We should be able to find out this information as it impacts us all. We should advocate for a decrease in the use of antibiotics in agriculture in New Zealand and across the world, especially as antibiotic resistance continues to increase.
Alternatives to antibiotics – phages
A phage (bacteriophage) is a virus that infects bacteria. So, like bacteria they can be used to treat and prevent bacterial infections. To kill bacteria, they enter the bacterial cell then replicate to make a large amount of copies then burst the cell by releasing all the copies.
Phage therapy is the use of phages to kill specific bacteria in our bodies and is an alternative to antibiotics. This can be done by people taking cocktails containing the phage that will target the host bacterium we wish to kill . This was done and is still practiced in some places in Russia and Eastern Europe. However, it is relatively new in the western world.
An example of a potential use is in the disease Tuberculosis (TB). It is in the top 10 causes of death in the world, having caused 1.8 million deaths in 2015 and infecting around a third of the population with latent TB . The overuse of antibiotics has accelerated the evolution of Mycobacterium tuberculosis becoming antibiotic resistant . If we could find a phage that could infect this bacterium we could have a potential cure for TB.
This year we have been finding phages that can infect the bacterium Mycobacterium smegmatis. This is similar to the TB bacterium and therefore there is potential that some phages may be able to infect both. Hence, we could be contributing to potentially finding a phage that could infect TB and we are definitely adding to the scientific pool of data about phages which will help us discover more about this very important field in the future. In my next blog post I’ll be discussing this journey and the phage that I found.
- World Health Organisation Antibiotic Resistance. 2016; Available from: http://www.who.int/mediacentre/factsheets/antibiotic-resistance/en/.
- World Health Organisation How to stop antibiotic resistance? Here’s a WHO prescription. 2015; Available from: http://www.who.int/mediacentre/commentaries/stop-antibiotic-resistance/en/.
- Antibiotic Resistance. Available from: http://www.health.govt.nz/your-health/conditions-and-treatments/treatments-and-surgery/medications/antibiotic-resistance.
- Timothy F. Landers, R., CNP,, et al., A Review of Antibiotic Use in Food Animals: Perspective, Policy, and Potential. Public Health Reports, 2012. 127.
- Industries, M.f.P. Antibiotics and resistance. 2017; Available from: https://www.mpi.govt.nz/food-safety/whats-in-our-food/chemicals-and-food/agricultural-compounds-and-residues/antibiotics-and-resistance/.
- Benjamin K Chan, S.T.A.C.L.-C., Phage cocktails and the future of phage therapy. Future Microbiology, 2013. 8(6): p. 769–783.
- World Health Organisation Tuberculosis. 2017; Available from: http://www.who.int/mediacentre/factsheets/fs104/en/.
- Nguyen, L., Antibiotic resistance mechanisms in M. tuberculosis: an update. Arch Toxicol, 2016. 90(7): p. 1585-604.