Controlling the spread of diseaseSpec 10.1.5
In short
The spread of disease is controlled by breaking transmission routes so fewer people take in pathogens. The main measures are a clean water supply, hygienic food preparation, good personal hygiene, waste disposal and sewage treatment. For example, treating drinking water and sewage stops water-borne diseases such as cholera from spreading.
Good public health stops pathogens reaching people in the first place. Each measure breaks a transmission route, so fewer people take in the pathogen.
| Measure | Why it is important |
|---|---|
| A clean water supply | Drinking water is treated so it does not contain pathogens. This stops water-borne diseases, such as cholera, spreading. |
| Hygienic food preparation | Washing hands and surfaces, cooking food thoroughly and storing it correctly stops pathogens getting into food or growing in it. |
| Good personal hygiene | Washing hands, especially after using the toilet and before eating, removes pathogens and stops them being passed on. |
| Waste disposal | Rubbish is removed and dealt with so that pathogens in it cannot contaminate food, water or surfaces, and animals that carry pathogens are not attracted. |
| Sewage treatment | Sewage contains pathogens from human faeces. Treating it means it does not contaminate drinking water or food crops. The stages of sewage treatment are not required. |
Exam tip:
Link every measure to a route: the pathogen is kept out of water, food or off hands. 'It keeps things clean' earns no mark.
Written and checked against the Cambridge IGCSE Biology (0610) specification · Updated October 2026