disorders of human health that result from infection caused by living pathogens (viruses, bacteria, rickettsia, fungi, helminths, ticks, other pathogenic parasites); transmitted from infected persons to healthy ones, and tend to mass spread See also: contagious diseases; infectious diseases;

A tissue zinc/copper ratio of less than 4.00/1 is frequently associated with an increased susceptibility to bacterial and viral infections. Copper toxicity may predispose to infections by displacing zinc. Normally, to combat infections, copper is mobilized from the liver. If copper is biounavailable and cannot be mobilized, susceptibility to infections increases.

The invasion of an organism or toxin in the body that causes injury or harm to the surrounding area.