Health and Hygiene
Health and Hygiene
This domain tests communicable and non-communicable diseases, pathogens, vectors, immunity, vaccination, personal and community hygiene, and the effects of tobacco and alcohol.
Core rules
- Communicable diseases spread by pathogens such as bacteria, viruses, protozoa and fungi; non-communicable diseases are not transmitted, e.g. diabetes and hypertension.
- Malaria is caused by Plasmodium and spread by the female Anopheles mosquito; dengue is viral and spread by Aedes.
- Tuberculosis is bacterial and spreads through droplets; AIDS is caused by HIV and spreads through unprotected sex, infected blood and from mother to child.
- Immunity may be innate or acquired; vaccination exposes the body to a weakened or inactivated antigen to produce antibodies and memory cells.
- Hygiene includes safe water, sanitation, handwashing, food safety and vector control.
- Tobacco and alcohol are addictive and increase cancer, liver and heart disease risk.
Worked example
A child is vaccinated against measles with a weakened measles virus. The immune system recognises the antigen, produces antibodies and forms memory cells without the child developing the disease. Later, if the real measles virus enters, memory cells respond quickly and prevent illness. This is active acquired immunity, not a direct injection of ready-made antibodies.
Traps
Antibiotics do not cure viral infections such as the common cold. Vaccination prevents disease; it is not a treatment after infection. A vector is not the pathogen. Being immune does not mean never exposed; it means the body responds effectively.