Foundations of Public Health

ALL KEY TERMS

Public Health

The practice of protecting and improving the health of people and communities.

Preventing Epidemics and the Spread of Disease

Stopping diseases from spreading and protecting people from getting sick.
Example: Vaccines and quarantine during outbreaks.

Protecting Against Environmental Hazards

Making sure air, water, and food are safe and protecting people from harmful chemicals or radiation.

Example:
Testing water for lead to keep drinking water safe.

Preventing Injuries

Keeping people safe by reducing accidents at work, home, or in public.

Example:
Using seat belts and having traffic lights to prevent car crashes.

Promoting and Encouraging Healthy Behaviors

Teaching people how to live healthy lives.
Example: Campaigns to stop smoking or eat healthy.

Responding to Disasters and Assisting Communities in Recovery

Helping people and communities after emergencies like floods, fires, or pandemics.
Example: Providing clean water and shelter after a hurricane.

Ensuring the Quality and Accessibility of Health Services

Making sure everyone can get good, affordable healthcare.

Example:
Offering free clinics for people without insurance.

Germ Theory

The idea that tiny organisms like bacteria and viruses cause many diseases.
Example:
Getting sick from touching a surface with flu germs.

Miasma Theory

The old belief that "bad air" or smells caused diseases.
Example:
People once thought cholera came from dirty-smelling air, not water.

Centralized Public Health Structure

Simple Definition:
A national system where one main group controls public health decisions and funding.
Example:
The state government leads all vaccination programs.

Decentralized Public Health Structure

Local or regional groups make their own health decisions and manage resources.
Example:
A city health department runs its own COVID-19 testing sites.

Mixed-Structure System of Public Health

A blend of national and local control, where both levels work together on public health.
Example:
The national government gives funding, and local areas decide how to use it.

Shared Public Health Structure

Public health work is shared by state, local groups, and sometimes private organizations.
Example:
A city teams up with a hospital and state agency to run a health fair.

Assessment

Checking and understanding the community’s health needs and problems.
Example:
Collecting data on how many people have diabetes in a city.

Policy Development

Creating rules and plans to solve public health problems.
Example:
Making a law to ban smoking in public places.

Assurance

Making sure health services and rules are followed and available to everyone.
Example:
Providing free vaccines and checking that clinics meet safety standards.

Contributory Causes

Things that help cause a disease, either directly or indirectly.
Example:
Smoking contributes to lung cancer.

Genetics

Study of genes and how they affect our health.
Example:
Some people inherit a higher risk for diabetes.

Behavior

The choices people make that affect their health.
Example:
Exercising regularly is a healthy behavior.

Environmental and Physical Influences

The surroundings that affect health.

Natural + Human made
Example:
Clean air and safe housing improve health.

Natural Environment

Parts of nature that impact health, like air, water, and natural disasters.
Example:
Poor air quality can cause asthma

Built Environment

Man-made places like buildings, roads, and workplaces.
Example:
A neighborhood with sidewalks encourages walking.

Medical Care

Health services that help prevent or treat diseases.
Example:
Going to the doctor for a check-up or treatment.

Social Factors

The social and money-related conditions people live in.
Example:
Education and income can affect health.

Public Health Emergency of International Concern (PHEIC)

A serious global health threat declared by the WHO that needs worldwide action.
Example:
COVID-19 was declared a PHEIC in 2020.

Endemic Disease

A disease that is always present in a certain place or group.
Example:
Malaria is endemic in some parts of Africa.

Disease Vectors

Living things that spread disease.
Example:
Mosquitoes spread malaria.

Microorganisms

Tiny living things like bacteria and viruses that can cause disease.
Example:
The flu is caused by a virus.

Infectious Diseases

Diseases that spread from person to person through germs.
Example:
Tuberculosis is an infectious disease.

R Naught (R₀)

The number of people one sick person can infect.
Example:
If R₀ is 2, one person spreads the disease to two others.

Immunization

Getting a vaccine to protect against a disease.
Example:
Getting the measles shot to avoid infection.

Vaccination

Getting a shot or medicine to prevent disease.
Example: Flu shot.

Screening

Testing people to find out if they might have a disease early.
Example:
Checking people for COVID-19 at airports.

Treatment

Medical care to help someone recover from a disease.
Example:
Taking antibiotics for a bacterial infection.

Non Communicable Disease (NCD)

Diseases that don’t spread from person to person.
Example: Heart disease, cancer.

Environmental Health

Protecting people from health risks in the environment.
Example: Clean drinking water, safe food.

Social Determinants of Health

Social and economic conditions that affect people’s health.
Example:
Having a stable job and good education helps people stay healthy.

Ecological Model

A way to understand how people’s choices are affected by many levels, like themselves, their relationships, and their surroundings.
Example:
Eating habits can be shaped by family, school, and food access.

Health Belief Model

Explains how people’s beliefs affect their health choices.
Example:
Someone might get a flu shot if they believe they’re at risk.

Stages of Change Model

The Stages of Change Model explains how people change a behavior over time, step by step.
Developed by James Prochaska and Carlo DiClemente.

Precontemplation
The person doesn’t think they have a problem or isn’t ready to change.
Example: “I don’t need to stop smoking.”

Contemplation
The person is thinking about changing but hasn’t decided yet.
Example: “Maybe I should quit smoking.”

Preparation
The person makes a plan to change soon.
Example: “I’ll start cutting back next week.”

Action
The person is actively making the change.
Example: “I haven’t smoked in 3 days.”

Maintenance
The person keeps the new habit going long-term.
Example: “I’ve been smoke-free for 6 months.”

Social Cognitive Theory

Says people learn by watching others and that behavior is influenced by both people and their environment.
Example:
A child learns to eat vegetables by watching parents eat them.

Theory of Reasoned Action / Planned Behavior

Says people’s actions are based on what they believe, how they feel, and what they plan to do.
Example:
Someone who believes exercise is good and plans to join a gym is more likely to do it.

Modeling

Showing how to do something so others can copy it.
Example:
A teacher washes hands to show students how to stay clean.

Self-Efficacy

Believing you can do something successfully.
Example:
A person who feels confident in managing their diet is more likely to eat healthy.

Community Engagement

Working with a community to understand its needs and create health solutions together.
Example: Involving local leaders in a health fair.

Evidence-Based Public Health

Making public health decisions using good research, expert advice, and community values.
Example:
Choosing a diabetes program that worked well in other cities.

Causation

When one thing directly causes another.
Example:
Smoking causes lung cancer.

Correlation

When two things happen together but one doesn’t necessarily cause the other.
Example:
Ice cream sales and sunburns rise together, but one doesn’t cause the other.

Health Policy

Rules and plans made to improve health in a community or country.
Example:
A law that requires health insurance for all children.

Surveillance

Watching and collecting health data to help guide public health actions.
Example:
Tracking flu cases in a city to plan vaccine distribution.

Passive Surveillance

Getting health data from hospitals or clinics without asking for extra info.
Example:
Hospitals regularly reporting disease cases to a health department.

Active Surveillance

Simple Definition:
Health officials actively look for disease cases by contacting sources.
Example:
Calling doctors during an outbreak to ask about new cases.

Quarantine

Keeping people who may be exposed to a disease away from others.
Example:
Someone exposed to COVID-19 stays home even if they feel fine.

Isolation

Separating people who are sick from those who are healthy.
Example:
A person with measles is kept in a hospital room alone.

Police Power

The government’s right to make rules to protect public health.
Example:
Requiring vaccinations for school entry.

Epidemiologic Triangle

A model that shows how disease spreads: includes agent, host, and environment.
Example:
COVID-19 (agent), people (host), crowded places (environment).

Agent

The cause of a disease.
Example:
The flu virus is an agent of illness.

Host

The person or animal who can get the disease.
Example:
A person who catches the flu.

Environment

Outside factors that affect disease spread.
Example:
Cold weather can help flu spread more easily.

Virulence

How harmful or severe a disease is.
Example:
Ebola has high virulence.

Infectivity

How easily a disease spreads.
Example:
Measles has high infectivity—it spreads quickly.

Pathogenicity

How likely a germ is to cause illness.
Example:
Some germs are harmless, while others can make you very sick.

Antigenicity

How well a germ triggers an immune response.
Example:
Vaccines use parts with high antigenicity to protect us.

Holistic Framework

Looking at all parts of life—body, environment, lifestyle—to improve health.
Example:
Helping someone with asthma by treating symptoms and reducing air pollution.

Social Justice

The belief that everyone deserves fair access to healthcare.
Example:
Making sure low-income families get free vaccines.

Market Justice

Access and availability are determined by individuals' ability to pay and purchase services

Immunization

Protecting someone from a disease using a vaccine.
Example:
A child gets a measles shot to avoid getting sick.

Chronic

A health problem that lasts a long time.
Example:
Diabetes is a chronic condition.

Atherosclerosis

Plaque buildup in arteries that blocks blood flow.
Example:
Can lead to heart attacks or strokes.

Situational Awareness

Understanding what’s happening during an emergency to respond wisely.
Example:
Knowing flood areas and who needs help first.

Emergency Preparedness

Planning ahead to handle disasters or outbreaks.
Example:
Having food, water, and safety plans before a hurricane hits.

Health Belief Model:

The Health Belief Model explains why people take or avoid health actions. It includes:

1. Perceived Susceptibility
   What it means: Do I believe I could get the disease?
   Example: “I might get the flu this winter.”

2. Perceived Severity
   What it means: How serious do I think the disease is?
   Example: “The flu can make me really sick and keep me out of work.”

3. Perceived Benefits
   What it means: Will taking action help me avoid the disease?
   Example: “Getting a flu shot can protect me from getting sick.”

4. Perceived Barriers
   What it means: What’s stopping me from taking action?
   Example: “The flu shot might hurt or I don’t have time to go.”

5. Cues to Action
   What it means: What reminds or pushes me to act?
   Example: “I saw a news ad about flu season starting,” or “My friend just got the flu.”

6. Self-Efficacy
   What it means: Do I feel confident I can take the action?
   Example: “I know how to schedule an appointment and get the shot.”

Social Cognitive Model

Social Cognitive Theory says people learn behaviors by watching others, copying actions, and being influenced by their environment and beliefs.
Developed by Albert Bandura.

Reciprocal Determinism:
The idea that a person’s behavior, environment, and personal beliefs all influence each other.
Example: A friendly person (belief) in a supportive gym (environment) keeps exercising (behavior).

Self-Efficacy:
A person’s confidence in their ability to do something.
Example: “I believe I can stick to my workout plan.”

Observational Learning:
Learning by watching others.
Example: Seeing a friend eat healthy may inspire you to do the same.

Outcome Expectations:
Beliefs about what will happen after a behavior.
Example: “If I quit smoking, I’ll feel healthier and save money.”

Reinforcements:
Rewards or punishments that influence whether a behavior is repeated.
Example: Getting praise for exercising makes you want to keep doing it.

Social Ecological Model

The Social Ecological Model explains how health is influenced by many layers—from personal choices to laws. To solve health problems, we need to act on multiple levels.

Individual Level:
A person’s knowledge, attitudes, and behaviors.
Example: Choosing to eat healthy or exercise.

Interpersonal Level:
Close relationships that influence health, like family, friends, or peers.
Example: Friends encouraging you to quit smoking.

Organizational Level:
Workplaces, schools, or other organizations that affect health.
Example: A school offering healthy lunches or a workplace wellness program.

Community Level:
Social networks, local culture, and relationships among organizations.
Example: Community centers offering free fitness classes.

Public Policy Level:
Laws, rules, and policies that support or limit health actions.
Example: A law banning smoking in public places.

American Indian and Alaska Native

American Indian and Alaska Native tribes have always believed that good health means more than just not being sick. They focus on the whole person—body, mind, spirit, and emotions—and also believe that being healthy is connected to taking care of the land, nature, and community.