DEFINITIONS+OF+HEALTH+AND+ILLNESS+page+86


 * PATHOGEN: Any microorganim (viruses, bacteria, fungi, protozoa) which causes an infectious disease.
 * IMMUNE RESPONSE: Series of processes carried out by the immune system when attacked by a pathogen.
 * ANTIBIOTIC: Natural or synthetic substance which destroy or prevents the reproduction of bacteria without harming the cells or the organism.
 * VACCINE: Artificial preparation of the weakened or dead pathogen, which does not trigger (provoke) the disease but which activates the immune system, producing immunity to that pathogen.