Immunity: The Body’s Defense
Immunity is the body’s natural ability to fight diseases.
- Innate Immunity: Protection we are born with.
- Acquired Immunity: Protection developed after exposure to a disease or a vaccine.
Vaccines: Prevention is Better than Cure
A vaccine trains the immune system to recognize a pathogen without causing the disease. It usually contains dead or weakened germs.
The Story of Smallpox
- Observation: Edward Jenner (1796) noticed milkmaids who got Cowpox (mild) never got Smallpox (deadly).
- Experiment: He infected a boy with Cowpox, then exposed him to Smallpox. The boy survived.
- Result: The first vaccine was created. Today, Smallpox is eradicated from the world.
Antibiotics: Fighting Bacteria
Antibiotics are medicines that kill or stop the growth of bacteria.
- Discovery: Alexander Fleming discovered Penicillin (the first antibiotic) from a mould in 1928.
- Limitation: Antibiotics ONLY work against Bacteria. They do NOT cure viral infections like the Common Cold or Flu.
Note
Antibiotic Resistance: If we overuse antibiotics or don’t finish the prescribed course, bacteria can adapt and survive. These “superbugs” become very hard to kill. Rule: Only take antibiotics prescribed by a doctor.