Evolution of Antibiotic Resistance in Pathogenic Bacteria
Definition
Antibiotic resistance
Antibiotic resistance occurs when bacteria evolve mechanisms to survive exposure to antibiotics that would normally kill them.
- It evolves by natural selection, through four main mechanisms:
- Genetic Variation: Within a bacterial population, some cells carry mutations that make them less susceptible to antibiotics.
- Selective Pressure: When exposed to antibiotics, most bacteria die, but resistant ones survive.
- Survival and Reproduction: Resistant bacteria reproduce, passing on their advantageous traits.
- Spread of Resistance: Over time, the resistant strain becomes dominant in the population.
Antibiotic resistance is a growing threat, making once-treatable infections potentially deadly.
Evolution of Multiresistant Bacteria
Some bacterial strains have evolved resistance to multiple antibiotics, making them extremely difficult to treat.Example
MRSA (Methicillin-Resistant Staphylococcus aureus) is resistant to multiple antibiotics and poses a serious threat in healthcare settings.
Careful Use of Antibiotics Slows the Emergence of Resistance
- To slow the evolution of antibiotic resistance, antibiotics should be:
