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a person or animal that transmits a disease-causing organism to others. Typically, the carrier suffers no symptoms of the disease


the strength of an intoxicant, as measured by the amount needed to produce a certain response


lack of sensitivity to a drug, insecticide, etc., esp. as a result of continued exposure or genetic change.


the state or fact of being likely or liable to be influenced or harmed by a particular thing


an organism, typically a biting insect or tick, that transmits a disease or parasite from one animal or plant to another.


a chemical that can kill bacteria without harming a persons cell


a molecule that the immune system recognizes either as part of the body or as coming form outside the body

Infectious Disease

a disease caused by the presence of a living thing in the body

Noninfectious Disease

a disease that is not caused by a pathogen


an organism that causes diseases


a poison produced by bacterial pathogens that damages cells.

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