Incubation Period Definition
Incubation period is the length of time between the exposure to a PATHOGEN and the appearance of symptoms or illness. Incubation periods vary from a few hours (illnesses such as CHOLERA and SHIGELLOSIS) to months (illnesses such as HEPATITIS C, TUBERCULOSIS, and AMEBIASIS).
Some diseases, such as AIDS (acquired immunodeficiency syndrome) and HUMAN PAPILLOMAVIRUS (HPV), may have incubation periods of years. During the incubation period the pathogen replicates until its presence reaches a level that can overcome the immune system’s efforts to contain it. Viral infections in particular may be contagious during the incubation period.