7: Infectious Diseases
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- Infectious diseases are distinguished from other illnesses and disorders because they can be transmitted from someone who is ill either directly or indirectly to other individuals, who then develop the same infectious disease and are also able to pass it on. A familiar example is the ‘common cold’ which almost everyone has experienced at some time in their lives . Non-human animals and plants also suffer from infectious diseases, which cause massive losses to food crops and livestock.
- 7.2: What Causes Infectious Diseases?
- Infectious diseases are transmitted between individuals by infectious agents, known as pathogens, from the Greek word pathos (to suffer) and genès (to produce). Pathogens produce a lot of human suffering and disability across the world, including in relatively wealthy nations like the United States. Most people have heard of at least some types of pathogen, for example bacteria or viruses.