What is it
Students study communicable diseases caused by viral, bacterial, fungal and protist pathogens, how the body's specific and non-specific immune defences work, vaccination, and how new medicines and drugs are developed and tested.
Why it matters
This topic gives students the scientific literacy to critically evaluate health claims and understand real public-health issues like vaccination and antibiotic resistance — genuinely useful beyond the exam.
Exam tip
Learn one named example disease per pathogen type (e.g. measles-virus, salmonella-bacterium, athlete's foot-fungus, malaria-protist) — exam boards frequently require a specific named example, not just the category.
Related topics
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