Final answer:
The incubation period is important to track and identify the progression of a disease and to determine the period during which infected individuals can spread the disease.
Step-by-step explanation:
The duration of the incubation period is important because it is the time between infection and the first appearance of symptoms. Knowing the incubation period allows healthcare professionals to track and identify the progression of a disease. It also helps in determining the period during which infected individuals can spread the disease to others. For example, in the case of influenza, the incubation period is approximately 1-2 days, during which infected individuals can spread the virus to others for about 5 days after becoming ill.