You may ask yourself why antibiotic resistance is becoming such a huge problem right now and how it can be a major threat to global health. Some of the many reasons for this are addressed in this section.
Antibiotic resistance is a natural phenomenon
Firstly, it is important to understand that antibiotic resistance is a natural phenomenon. The pathways for producing antibiotics have existed for millions of years. Many microbes in the environment naturally produce antibiotics. Microbes use these molecules to communicate and compete with other organisms for space and resources.
For as long as there have been antibiotics, there have been microbes that can survive their action. Long before antibiotics were introduced as medicines, resistance mechanisms existed in environmental bacteria and antibiotic-producing microbes used them for protection. However, antibiotic resistance was not common in pathogenic bacteria.
In the eighty years humans have used antibiotics, resistance has become common in both environmental and pathogenic bacteria. There has been, and continues to be, widespread use of antibiotics in the healthcare, veterinary, and agricultural sectors, creating strong selection pressure for resistant bacteria. The human use of antibiotics has also led to the accumulation of these drugs in various environments, where antibiotic-resistant bacteria can thrive. This has contributed to the selection and spread of bacteria resistant to multiple antibiotics.
Video describing antibiotics and the spread of antimicribial resistance, the threat to human health and agriculture and what can be done to take action. Read more on how to take action in What can I do?
Where do resistance genes come from?
It is not fully clear where the resistance genes in pathogenic bacteria originated. Large scale antibiotic use in medicine and other applications created selective pressure for resistant bacteria. This also facilitated the spread of resistance mechanisms between bacteria. In some cases, researchers have traced resistance genes in pathogens to environmental bacteria. However, this is often not possible. Many resistance genes in pathogens likely served a different function before evolving to provide resistance.
Selected Resources
| Resource | Description |
|---|---|
| Q&A: Antibiotic resistance: where does it come from and what can we do about it? | Journal article that provides a comprehensive overview and detailed answers to the most common questions regarding antibiotic resistance (6 pages with images). |
| Drivers, Dynamics and Epidemiology of Antimicrobial Resistance in Animal Production | Report that explains and discusses the development and spread of antibiotic resistance and its relations with food production (by FAO, 39 pages + references and appendices). |