Natural History of Disease
The Natural History of Disease refers to the progression of a disease process in an individual over time, in the absence of treatment. It serves as the foundation for the levels of prevention.
Stages & Prevention Levels
| Stage | Prevention Level | Focus |
|---|---|---|
| Pre-pathogenesis | Primary | Health promotion & Specific protection (e.g., vaccines). |
| Early Pathogenesis | Secondary | Early diagnosis & Prompt treatment (e.g., screening). |
| Late Pathogenesis | Tertiary | Disability limitation & Rehabilitation. |
High-Yield Clinical Notes:
- Pre-pathogenesis Phase: The period before the disease agent interacts with the host. Focuses on the “Epidemiological Triad.”
- Pathogenesis Phase: Starts when the host begins to react to the agent. This includes the “incubation period” (infectious) or “latency period” (chronic).
- Clinical Horizon: The point at which the disease becomes clinically detectable. Screening aims to move diagnosis to the left of this horizon.