Three Tiers of Health Prevention
Public health splits prevention into three levels based on when they intervene in a disease's natural course. Primary prevention acts before disease onset to stop it entirely, using vaccination and safety rules.
| Level | Timing | Example |
|---|---|---|
| Primary | Before disease | Vaccination |
| Secondary | Early, before symptoms | Cancer screening |
| Tertiary | After establishment | Rehab |
Secondary prevention catches disease early before symptoms worsen, like cancer screenings. Tertiary prevention manages established disease and limits complications, like cardiac rehab after a heart attack.
The Ottawa Charter & Population Health
The WHO's 1986 Ottawa Charter for Health Promotion reframed health as a societal project across multiple levels: healthy public policy, supportive environments, community action, personal skills, and reoriented health services.
Health is produced by social conditions, not just medical encounters. Common pitfall: treating prevention as undifferentiated. Confusing early screening with stopping disease creates flawed, non-interchangeable public health policies.