Medicine often defines diseases by the effects, i.e. the symptoms and findings, rather than root causes. When new effects are observed, during the infectious cascade, a new disease may be named. Chronic diseases arising from the same or different infectious pathogens often have numerous named variations, or sub-parts of the same chronic disease, as new effects are observed over time or in different patients, and named a new chronic disease.

Naming diseases based on effects rather than causes leads to thousands of named diseases; confusion among patients, researchers, and between medical specialties; inefficiency and undue expense, in patient care and research; an explosion of symptomatic treatments and the risk of harmful medications being prescribed; and the failure of research to discover new ways to conquer chronic disease.