Unformatted text preview: microorganism, often a normal resident, after the body's defenses have weakened. Modes of disease transmission. When a disease remains in a population, a source of pathogens called a reservoir of infection exists within the population. The reservoir can be human, animal, or nonliving, such as the soil. A human reservoir who has had the disease and recovered but continues to shed infectious organisms is called a carrier. Animal diseases spread to humans are called zoonoses. Among the principal routes of transmission of disease are contact, vectors, and vehicles. Contact can be direct or indirect. Direct transmission occurs from person to person by such things as touching, kissing, and sexual intercourse ( Figure 1 ). Indirect transmission occurs when a nonliving object is intermediary between two humans....
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- Fall '07
- acute disease, blood constitute toxemia, relatively long time., carrier. Animal diseases