Antimicrobial Resistance

- Antibiotics: Chemicals that kill bacteria and some fungi.
→ Fleming discovered it by accident.
- Antibiotic resistance: When antibiotics don't kill bacteria.
→ Within 4 years of using the first antibiotic, some resistant strains were observed.

- There's variation in a bacterial population.
- Some may be more resistant to an antibiotic than others.
- The resistant ones will survive, reproduce, and pass on advantageous alleles to their offspring.
- Over many generations, a resistant strain will form.

- Antibiotics apply a huge selection pressure to bacteria and drive evolution forward so it happens faster.
- MRSA is a type of bacteria resistant to almost all antibiotics.
- If an antibiotic doesn't work, doctors can prescribe another.
- Only very serious infections should resort to antibiotics.
- Resistance is also developing against antivirals (ARVs), antifungals, and antiprotozoals, so now the new term antimicrobial resistance (AMR) is used.
- AMR is occurring faster than it should because of overprescription antibiotics.

- It's important to always finish a prescribed course of antibiotics, even if you start to feel better.

- The antibiotics cause bacteria to multiply partway through, as remaining bacteria may become resistant to the antibiotic, causing them to feel better. Taking the antibiotic again after a relapse doesn't work as well to treat the bacteria.

Antibiotics and Antivirals

- Broad-spectrum antibiotics, such as penicillin, can affect a variety of bacteria and fungi, but narrow-spectrum antibiotics are for specific bacteria and fungi.

- When you start taking antibiotics (if you start to feel better quickly as the first lot of bacteria die), all weak bacteria die first.
- As a result, you feel better: Fewer toxins are released.
- If you stop, you haven't killed more resistant bacteria, which can survive and reproduce with less competition.

- Antiviral drugs are used for fighting viral infections by stopping them from replicating by targeting cells.
- It's difficult to kill viruses without damaging the body's tissues, as bacteria go inside your body through them to replicate: you can't destroy the virus without also killing the body cell.

Testing Antibiotics:

- The clear area around the antibiotic disc shows us the bacteria that have been killed/unable to grow: the bacteria around it have been killed.
- The larger the clear area, the more effective the antibiotic.