Public Health: Core Concepts, Frameworks, and Roles
Overview
Public health has made a significant impact on population health, saving lives. In the United States, from , life expectancy increased by over >30 years, and an estimated of these extra years are due to public health interventions.
Public health aims to keep populations healthy by preventing disease, prolonging life, and promoting health through the organized efforts of society.
What is health?
World Health Organization (WHO) defines health as a state of complete physical, mental, and social well-being, and not merely the absence of disease or infirmity.
This is a bold, ambitious goal that encourages looking beyond diseases to physical, mental, and social domains of health.
What is public health?
Public health is the science and art of preventing disease, prolonging life, and promoting health through the organized actions of society.
Public health vs clinical medicine
Clinical medicine (the clinician’s approach): focus on the immediate health issue and the individual case (e.g., after a car accident, treating the fracture).
Public health approach: a holistic view that asks how and why the event happened and what can be done to prevent it from happening again in the future.
Example questions to understand the accident’s context (not just the fracture):
Was there a problem with vision or driving skills? Was the driver under the influence of alcohol or drugs?
Were there laws governing driving and resources to enforce them? What were community norms and expectations around driving?
Did the individual have a good social support network to aid recovery and prevent recurrence?
Did digital media contribute to the accident? Was the road on which the accident occurred unsafe?
Were there commercial factors such as vehicles with inadequate safety features? Was the vehicle well maintained?
Could maintenance have been affordable? Did financial constraints play a role?
Did the person have a job that didn’t pay well? Could this be related to access to education?
Were good health services available and accessible to support treatment and recovery?
Determinants of health are the complex factors that influence health outcomes:
They include who people are, what they do, and the conditions in which they are born, grow, live, work, and age (the social determinants of health).
They also include commercial determinants (how markets, products, and corporate practices influence health) and digital determinants (impact of digital media and online information).
Public health emphasizes upstream factors—interventions that change the broader determinants of health to benefit the population as a whole, rather than only addressing the immediate clinical issue.
Determinants of health and the role of upstream factors
Health is shaped by the interaction of multiple determinants across material, social, and environmental contexts.
Social determinants of health (education, income, housing, employment, social support, etc.) influence health outcomes.
Commercial determinants (industry practices, marketing, product safety, affordability) and digital determinants (information quality, online accessibility) also play a role.
Upstream focus is essential to drive population-level improvements by addressing root causes, not just downstream symptoms.
How public health works: the WFPHA framework
The World Federation of Public Health Associations (WFPHA) provides a framework to understand public health activities.
Three core service areas:
Protection: safeguarding population health (e.g., controlling infectious diseases, managing environmental hazards, ensuring healthy work environments, and managing health emergencies).
Promotion: improving population health (e.g., promoting healthy behaviors across the life course and addressing determinants of health).
Prevention: preventing health issues before they occur (e.g., vaccination and screening programs).
Enablers that ensure these core areas operate effectively:
Governance and advocacy to influence policy and secure commitment for health goals.
Capacity: a sufficient, well-trained, and supported public health workforce.
Information: accurate, timely data to support health actions, including research, surveillance, monitoring, and evaluation.
Responsibility for public health
The responsibility for a healthy population lies with all sectors of society.
Health departments have a central role, but improvement requires coordinated efforts from a wide range of stakeholders and sectors.
Key actors and sectors:
Other areas of government, the private sector, nongovernmental organizations (NGOs), international organizations, and local communities.
Across sectors such as education, finance, employment, housing, agriculture, veterinary, environment, and others, all united by the goal of improving public health.
Ongoing challenges facing public health
Climate change
Antimicrobial resistance
Emergence and spread of infectious diseases with pandemic potential
Health care in fragile, conflict-affected, and vulnerable settings
Increasing burden of non-communicable diseases (NCDs)
Addressing these challenges requires commitment and coordinated, collaborative efforts across all sectors of society.
Connections to broader themes and relevance
Public health frameworks guide policy development, resource allocation, and program design for population health improvement.
The approach emphasizes prevention, equity, and the social underpinnings of health outcomes.
Real-world relevance includes improving access to health services, ensuring safe environments, and shaping laws and norms that support healthier populations.
Ethical, philosophical, and practical implications (implied in the material)
Equity and access: upstream interventions imply addressing disparities in access to education, housing, and health services.
Balance between individual liberties and population health: enforcement of laws or regulations may require weighing personal choice against community safety.
Resource allocation: prioritizing prevention and protection programs may impact funding for clinical care and individual treatment.
Intersectoral collaboration: ethical imperative to engage diverse sectors (education, housing, transportation, industry) to achieve common health goals.
Data and surveillance ethics: collecting and using health data for surveillance and evaluation must respect privacy and proportionality.
Key takeaways (summary)
Health is a broad concept that extends beyond absence of disease to physical, mental, and social well-being.
Public health focuses on preventing disease and promoting health at the population level, using upstream strategies and the organized efforts of society.
The public health approach contrasts with clinical medicine by prioritizing population-level determinants and prevention rather than solely treating individual health issues.
Health determinants are multifactorial, including social, commercial, and digital factors; understanding these interactions is essential for effective action.
The WFPHA framework highlights three core service areas (Protection, Promotion, Prevention) and enabling factors (governance, capacity, information) to support actions.
Responsibility spans all sectors of society, requiring cross-sector collaboration and coordinated action.
Ongoing challenges require sustained, cooperative commitment across sectors to address climate change, antimicrobial resistance, pandemics, fragile settings, and NCDs.
The material emphasizes practical implications such as policy, accessibility, and equity, alongside the broader ethical considerations of population health.
Notable numerical references from the transcript (in LaTeX)
Life expectancy increase in the United States from : >30 years
Portion of life expectancy gains attributed to public health interventions: years
These figures illustrate the impact of public health interventions on population health over the 20th century.
Helpful connections to further study
Relate these concepts to epidemiology: measures of health outcomes, determinants, and surveillance data.
Link to health systems and policy courses: governance, advocacy, resource allocation, and intersectoral collaboration.
Consider real-world case studies on vaccination programs, environmental health measures, and injury prevention to see these core areas in action.