I should perhaps explain primary prevention is to stop you getting the disease. So preventing people inhaling cancinogens, either at work (asbestos) or leisure (tobacco products). Or Immunisation against infectious diseases, polio is a great example, so for our US readers is measles immunisation. Stops death permenant disability and handicap in the immunised individual.
Food and Water hygiene are in this category too, hence the failure of Water cos is increasing NHS costs.
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