Principles of Human Health

• Health is a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity.
• It is influenced by individual characteristics and behaviours, social interactions, and the physical environment.
• It is essential to understand that healthy lifestyle choices such as regular physical activity, balanced diet, adequate sleep, and avoidance of substances like tobacco and excessive alcohol can greatly contribute to overall health and wellbeing.

Disease Development and Progression

• A disease is a disorder of structure or function in a human that is not due to any immediate external injury.
• Diseases can be caused by various factors including infections, genetic disorders, poor nutrition, environmental factors, and stress.
• Disease progression refers to the course a disease takes from its initial stage to its final stage. The rate of progression can vary depending on numerous factors.
• In many cases, early diagnosis and effective treatment can slow disease progression and improve quality of life.

Disease Prevention and Control

• The aim of disease prevention and control is to reduce the impact of diseases on individuals and communities through interventions that reduce exposure to disease, reduce susceptibility to disease, or reduce the environmental conditions that facilitate disease transmission.
• Primary prevention refers to interventions that prevent disease occurrence (e.g., vaccines, health education promoting healthy lifestyles).
• Secondary prevention involves screenings and tests for early detection and treatment of disease (e.g., cancer screenings).
• Tertiary prevention aims to alleviate the effects of the disease and prevent disease-related complications (e.g., physical therapy for stroke victims).

Disease Models

• Biological models of disease view diseases as biomedical conditions caused by microorganisms, genetic or biochemical abnormalities.
• Sociological models view health and disease in the context of social conditions and behaviours, such as individual lifestyle choices, economic conditions, and social networks.
• Psychosocial models integrate biological and sociological models and consider the interaction between social, psychological and biological factors in understanding health and disease.

Health Disparities

• Health disparities are differences in health outcomes between groups due to factors such as race or ethnicity, socioeconomic status, gender, and geographical location.
• Health disparities can be reduced by addressing social determinants of health (e.g., education, income) and ensuring equitable access to healthcare services.