Final answer:
The progression of an infection from vague discomfort to specific signs and symptoms is described by the various periods of disease, including the prodromal period and the period of illness.
Step-by-step explanation:
The progression of an infection from vague discomfort to specific signs and symptoms is described by the different periods of disease. These periods include the incubation period, prodromal period, period of illness, period of decline, and period of convalescence. During the prodromal period, the patient begins to present general signs and symptoms of illness, which are typically non-specific and may include fever, pain, soreness, swelling, or inflammation. The period of illness follows the prodromal period and is marked by the most obvious and severe signs and symptoms of the disease.