Infectious Disease - A type of illness caused by a pathogenic agent, including viruses, bacteria, fungi, protozoa, parasites, or abnormal proteins known as prions.⏎
Host - An organism that harbors a parasite or another organism where there is a symbiotic relationship between the two organisms. In some cases, the relationship is commensal, or mutually beneficial, but in the case of a parasite and host, the host may be hurt by the parasite's presence.⏎
Incubation Time - The period of time between exposure to an infectious agent and the appearance of symptoms of the infection or disease it causes.⏎
Habitat - The specific geographical area or physical environment that is inhabited by an organism or a population of organisms.⏎