6.3.7 Resistant Bacteria

How Resistance Develops:

• Rapid Reproduction: Bacteria reproduce quickly, allowing for frequent opportunities for genetic mutations.
• Mutation and New Strains: During reproduction, mutations can occur, leading to the development of new genes, including those that confer antibiotic resistance. This results in the emergence of new resistant strains.
• Selection Pressure: When exposed to antibiotics, bacteria with resistance genes survive while those without these genes die off. This creates a selection pressure favouring the resistant bacteria.
• Reproduction and Spread: The surviving resistant bacteria reproduce and pass on their resistance genes to their offspring, leading to a population dominated by resistant strains.
• Rapid Spread: Bacterial diseases caused by resistant strains spread quickly because the population is not immune to these new strains, and there are limited effective treatments available.

Example: MRSA

• MRSA (Methicillin-resistant Staphylococcus aureus) is a well-known "superbug" resistant to multiple antibiotics.
• It is particularly problematic in hospitals, where it spreads easily as healthcare workers move between patients.

Strategies to Slow the Development of Antibiotic Resistance:

1. Judicious Use of Antibiotics:

• Avoid prescribing antibiotics for viral infections or non-serious conditions where they are ineffective.

2. Targeted Antibiotic Use:

• Use specific antibiotics tailored to the particular bacterial infection to avoid unnecessary exposure.

3. Completing Antibiotic Courses:

• Patients must complete the full course of antibiotics to ensure all bacteria are eliminated, reducing the chance of survivors mutating into resistant strains.

4. Reducing Antibiotic Use in Agriculture:

• Limit the use of antibiotics in livestock to essential cases, as overuse can lead to resistant bacteria that can transfer to humans through food consumption.

Strategies to Slow the Spread of Resistant Bacteria:

1. Maintain High Standards of Hygiene:

• Ensure rigorous hygiene practices in hospitals to prevent the spread of resistant bacteria.

2. Hand Hygiene:

• Medical staff and visitors should wash their hands regularly to reduce transmission.

3. Proper Use of Protective Clothing:

• Medical staff should wear disposable or regularly sterilised clothing to minimise the spread of bacteria.

Challenges in Combatting Resistant Bacteria:

• Development Lag: The development of new antibiotics is slow and costly, making it challenging to keep pace with the evolution of resistant bacterial strains.