Natural history of a communicable disease describes the progression of the disease in an individual over time, in the absence of intervention, from the stage of susceptibility to recovery, disability, or death. It helps community health nurses understand points where prevention and control measures can be applied effectively. For example, tuberculosis (TB) can be used to explain the natural history of a communicable disease. The process begins with the stage of susceptibility, where a person is healthy but at risk of infection due to factors such as poor nutrition, overcrowding, low immunity, or close contact with an infected individual. At this stage, primary prevention like health education, improved living conditions, and vaccination (BCG) can reduce risk. The next stage is the stage of exposure and subclinical disease. Here, the individual inhales Mycobacterium tuberculosis bacteria through airborne droplets. The bacteria enter