Antibiotic Resistance

Key Stage 4

Meaning

Antibiotic resistance is the tendency of bacterial colonies to become immune to the use of antibiotics.

About Antibiotic Resistance

Antibiotic resistance is evidence for evolution by natural selection.

The process of antibiotic resistance of a colony of bacteria takes place over several generations.

1. Antibiotics are used to kill a colony of bacteria.
2. Bacteria within the colony are all slightly different due to genetic variation so a few may not be affected by the antibiotic.
3. Some bacteria survive the antibiotic due to a number of reasons, but a proportion of those is due to a variation that has made them resistant.
4. In the next generation there will be many more resistant bacteria since the others have died and cannot reproduce.
5. When antibiotics are used again this removes all of the non-resistant bacteria leaving behind an entire colony of antibiotic resistant bacteria.

As a result of evolution many disease causing bacteria can no longer be treated with common antibiotics.

Doctors are concerned that if common Pathogenic Bacteria become antibiotic resistant then many diseases may become untreatable and thousands could die.

Reducing the Chances of Antibiotic Resistance

There are a number of precautions we can take to reduce the chance of Pathogenic Bacteria gaining antibiotic resistance. These include:

• Only giving antibiotics for serious infections that are known to be caused by Pathogenic Bacteria.
• Increased hygiene in hospitals.
• Quarantine people with antibiotic resistant strains of bacteria.
• Stop using antibiotics on livestock.

Examples

• MRSA - Methicillin Resistant Staphylococcus Aureus are a strain of bacteria which is not affected by a common antibiotic known as Methicillin.
• Super Gonorrhea - This sexually transmitted disease is resistant to many common antibiotics.