State the term - Infection

Infection is the invasion of the body by disease-producing (pathogenic) microorganisms and the reaction of the tissues to their presence and to the toxins generated by them. Because the central nervous system can be invaded by a wide variety of infectious agents-including viruses, bacteria, fungi, and metazoan parasites-the diagnosis and treatment of infection are important components of clinical neurology. Infections of the nervous system are particularly serious because the affected neurons and glia usually die, leaving permanent lesions.