Primary prevention, also known as etiological prevention, refers to taking comprehensive preventive measures against pathogenic factors or risk factors before the onset (or disease-free period) in order to prevent or reduce the occurrence of diseases, including preventive measures against people or the environment. The former is to improve health knowledge and self-care ability through health education, change unhealthy lifestyle, adhere to reasonable nutrition, physical exercise and planned immunization, and give priority to excellent children and education. Maternal and child health care, etc. The latter's preventive measures for the environment are to create and maintain a healthy natural and social environment, including improving the living and production environment and eliminating the damage caused by biological, chemical and physical factors to the human body.
Secondary prevention, also known as pre-clinical prevention or three-early prevention, refers to the preventive measures of early detection, early diagnosis and early treatment when the disease is still in the pre-clinical or early stage, with the aim of preventing or slowing down the development of the disease.
The secondary prevention of infectious diseases should include early isolation and early reporting measures in addition to "three early"; The positive significance of secondary prevention lies in controlling the source of infection, cutting off the route of transmission and preventing the spread of the epidemic. For non-infectious diseases, the earlier the diagnosis, the better the prognosis.
Measures include general survey, regular inspection, focusing on monitoring high-risk groups and specialist clinics.
Three-level prevention, also known as clinical prevention, refers to taking active treatment and rehabilitation measures in clinical or rehabilitation period, aiming at preventing disability, promoting functional recovery, improving quality of life and prolonging life.