negative result in a serological test; that is, the inability to detect the antibodies or antigens being tested for.
positive result in a serological test.
the characterization of a microorganism based on the kinds and combinations of constituent antigens present in that organism; a taxonomic subdivision of bacteria based on the above.
any virus causing a disease characterized by a very long preclinical course and a very gradual progression of symptoms.
a subgrouping of organisms within a species, characterized by some particular quality.
a set of symptoms that may occur concurrently.
the bacterium that causes tuberculosis, Mycobacterium tuberculosis.
a procedure, not used today, in which material from the pustule of an individual infected with smallpox (variola virus) was scratched into the skin of an infected person to induce immunity to the disease.
a carrier, especially an arthropod, that transfers an infective agent from one host (which can include itself) to another.
transmitted from one host to another by a vector.
the degree of pathogenicity of an organism as evidenced by the severity of resulting disease and the organism's ability to invade the host tissues.
a disease of animals transmissible to humans.
the population of animals infected with nonhuman microbes that present a potential threat of transmission to humans.