Differentiate the terms in each of the following pairs:
a. etiology and pathogenesis
b. infection and disease
c. communicable disease and noncommunicable disease
Most of the world’s population in less developed and developing countries have been infected with EBV human herpesvirus 4 by age one and show no ill effects, even where medical care is poor. In contrast, individuals in industrialized countries are ordinarily infected after puberty, and these older patients tend to have more severe reactions to infection despite better overall health and access to medical care. Explain this apparent paradox.