Background: Antibiotic resistance has progressed over many decades and is increasingly problematic. This paper gives a short summary of antibiotic resistance and its biology.
Material and methods: The authors have worked in this field for many years. References to major overviews and important work are given, but no systematic literature search has been done.
Results: Development of resistance is driven by positive selection of resistant clones of bacteria. There are multiple, often interlinked molecular mechanisms behind this resistance, and they all lead to a less effective interaction between antibiotics and their target.
Interpretation: Many observations of antibiotic resistance phenomena and their development over the last decades indicate that the problem is substantial, persisting and increasing. It will probably have an important impact on many medical disciplines in the future. Work to counteract this development is needed in every medical field in order to halt and hopefully counteract resistance development as strongly as we can.