HLTH 310: Introduction to Public Health Exam 1 Review Guide

Chapter 1: What is Public Health?

1. Definition of Public Health

   • Public health is the science and practice of protecting and improving the health of communities through education, policy-making, and research for disease and injury prevention. Unlike medical care, which focuses on individuals, public health focuses on populations.

2. Mission of Public Health

   • Public health aims to provide conditions in which people can be healthy. The central goal is to prevent disease and promote the overall health of communities.

3. Core Functions of Public Health

   • Assessment: Systematically collect, analyze, and make available information on healthy communities. Example: surveillance of disease outbreaks.

   • Policy Development: Develop public policies that support the health of the population based on scientific evidence. Example: smoking bans in public spaces.

   • Assurance: Ensure access to necessary health services through regulation and direct provision. Example: ensuring clean water supply and vaccination programs.

4. Difference Between Public Health and Medical Care

   • Public Health: Focuses on prevention (e.g., vaccines, clean water, education), populations, and long-term health strategies.

   • Medical Care: Focuses on treatment and curing individuals after they have become ill.

5. Levels of Prevention

   • Primary Prevention: Preventing disease from occurring (e.g., immunizations).

   • Secondary Prevention: Detecting disease early to slow or halt progression (e.g., screening tests like mammograms).

   • Tertiary Prevention: Minimizing disability from disease (e.g., physical therapy after a stroke).

Chapter 2: Why is Public Health Controversial?

1. Political vs. Individual Responsibility

   • Public health interventions often involve regulations that affect individual behavior (e.g., seatbelt laws, vaccination requirements). The balance between personal freedoms and public health safety can create controversy.

2. Economic Impact of Public Health Policies

   • Many public health measures (e.g., restrictions on alcohol or tobacco) can negatively impact businesses, creating opposition from industries affected by such regulations.

3. Moral and Religious Opposition

   • Public health issues such as sex education, contraceptive availability, or reproductive rights can conflict with religious or moral beliefs, leading to debates on these subjects.

4. Individual Liberties vs. Public Good

   • Some public health interventions (e.g., quarantine, mask mandates) limit individual freedoms for the greater good. This creates tension between individual rights and community health.

5. Public Health Measures and Perception

   • Public perception can influence the implementation of health measures. For example, anti-vaccine movements may resist vaccination campaigns even though they serve the public good.

Chapter 3: Powers and Responsibilities of Government in Public Health

1. State vs. Federal Roles in Public Health

   • State Governments: Primary responsibility for public health, with powers such as quarantine and disease control.

   • Federal Government: Provides funding and regulatory frameworks through agencies like the CDC, FDA, and NIH. It also exercises authority under the Commerce Clause to regulate public health across state borders (e.g., preventing the spread of infectious diseases).

2. Federal Public Health Agencies

   • Centers for Disease Control and Prevention (CDC): Monitors and responds to disease outbreaks.

   • National Institutes of Health (NIH): Supports medical research.

   • Food and Drug Administration (FDA): Regulates food, drugs, and medical devices to ensure safety and efficacy.

3. Local Health Departments

   • Carry out essential public health services at the local level, such as restaurant inspections, immunization clinics, and health education.

4. Public Health Laws

   • Laws regulate behaviors (e.g., requiring vaccinations for school entry) to protect public health. States have the power to enact regulations for the welfare of their citizens, such as quarantines or sanitation measures.

Chapter 4: Epidemiology Part 1 – Epi 101

1. Definition of Epidemiology

   • The study of the distribution (who, when, and where) and determinants (why and how) of disease frequency in a specified population.

2. Key Questions in Epidemiology

   • Who is affected by the disease?

   • When did they get the disease?

   • Where is the disease occurring?

   • Why/How is it spreading?

3. Measuring Disease Frequency

   • Incidence: The number of new cases of a disease that occur during a specified period in a defined population.

   • Prevalence: The total number of existing cases (both new and old) in a population at a specific time.

4. Calculating Disease Frequency

   • Incidence Rate = (Number of new cases) / (Population at risk) over a defined period of time.

   • Prevalence Rate = (Number of existing cases) / (Total population) at a specific point in time.

5. Outbreak Investigations

   • Steps:

     1. Verify the diagnosis.

     2. Define a case (what qualifies someone as having the disease).

     3. Systematically find cases (active surveillance).

     4. Ask questions: Who? Where? When? (Person, place, time).

     5. Look for the common source of exposure.

6. Epidemic Surveillance

   • A system created to monitor and prevent the spread of diseases. It helps detect outbreaks and emerging diseases.

7. John Snow and Cholera

   • The first use of epidemiology to study and control a disease. Snow identified contaminated water as the source of cholera outbreaks in London in the mid-1800s.

Chapter 5: Epidemiology Part 2 – Types of Epidemiological Studies

1. Intervention Study (Randomized Controlled Trial)

   • Goal: Test the effectiveness of an intervention (e.g., a drug, vaccine).

   • Two groups:

     • Experimental Group: Receives the intervention.

     • Control Group: Receives a placebo or standard treatment.

   • Randomized, double-blind, placebo-controlled trials are the gold standard.

   • Example: Polio vaccine field trial (1954).

2. Cohort Study

   • Goal: Follow healthy individuals over time to see how their exposures affect their disease outcomes.

   • Relative Risk (RR): Measures the likelihood of disease in exposed versus unexposed groups.

     • RR > 1: Increased risk of disease.

     • RR < 1: Decreased risk of disease.

     • RR = 1: No association.

   • Example: Framingham Heart Study.

3. Case-Control Study

   • Goal: Compare people with a disease (cases) to healthy controls to identify past exposures that might have caused the disease.

   • Odds Ratio (OR): Measures the odds that an exposure is associated with the outcome.

     • OR > 1: Higher odds of disease with exposure.

     • OR < 1: Lower odds of disease with exposure.

     • OR = 1: No association.

   • Example: Zika and microcephaly case-control study.

Chapter 6: Ethical Issues in Public Health and Epidemiology

1. Tuskegee Syphilis Study

   • A tragic example of unethical public health research where African American men were denied treatment for syphilis, leading to significant health and social consequences.

2. Key Ethical Principles in Research

   • Informed Consent: Participants must be fully informed about the risks and benefits of a study before agreeing to participate.

   • Institutional Review Boards (IRB): Committees that ensure studies are ethical and protect the rights of participants.

3. Ethical Considerations in Public Health

   • Balancing individual rights and the public good. For example, enforcing vaccination mandates or quarantines may restrict personal freedoms but serve the collective health of society.

Key Concepts to Focus On

1. Prevalence vs. Incidence

   • Be able to define, differentiate, and calculate both.

2. Relative Risk (RR) and Odds Ratio (OR)

   • Understand how to interpret these statistics from cohort and case-control studies.

3. Study Designs

   • Know the differences between intervention, cohort, and case-control studies, and when each is used.

4. Public Health Ethics

   • Recognize the importance of informed consent and the historical significance of studies like Tuskegee.

Practice Questions

1. What are the three core functions of public health, and how do they contribute to population health?

2. Define incidence and prevalence, and provide an example of how they are calculated.

3. How does a randomized controlled trial differ from a cohort study?

4. What ethical guidelines must be followed in public health research, and why were they established after the Tuskegee Syphilis Study?

Chapter 1: Introduction to Public Health

1. What is Public Health?

   • The science and practice of protecting and improving the health of communities. It focuses on prevention and health promotion rather than individual medical care.

2. Core Functions of Public Health:

   • Assessment: Systematically collect and analyze data to identify health problems.

   • Policy Development: Develop policies and plans to support health efforts.

   • Assurance: Ensure that services are provided to improve the health of the population.

3. Difference Between Public Health and Medical Care:

   • Public Health: Aims at preventing disease and promoting health at the population level.

   • Medical Care: Focuses on diagnosing and treating individuals after they have become ill.

4. Public Health Disciplines:

   • Includes epidemiology, biostatistics, environmental health, health policy, and social and behavioral sciences.

5. Levels of Prevention and Examples:

   • Primary Prevention: Preventing disease (e.g., vaccinations).

   • Secondary Prevention: Early detection (e.g., screenings).

   • Tertiary Prevention: Reducing impact (e.g., rehabilitation).

6. The Public Health Approach to Addressing a Health Problem:

   • Define the problem, Identify risk factors, Develop and test interventions, Implement interventions, and Monitor and evaluate the interventions.

7. The Chain of Causation:

   • A model that illustrates the relationship between the agent, host, and environment in the occurrence of disease.

Chapter 2: Controversy and Public Health

1. Sources of Controversy and Examples:

   • Conflicts between individual rights and public health mandates (e.g., vaccination laws, smoking bans).

2. Why is Public Health Inherently Political?

   • Public health policies often involve government regulations that can impact individual freedoms and societal norms, leading to debates on ethics, rights, and resources.

Chapter 3: Powers and Responsibilities of Government

1. Branches of Government:

   • Legislative: Creates laws (Congress).

   • Executive: Enforces laws (President and federal agencies).

   • Judicial: Interprets laws (Court system).

2. Functions of the CDC:

   • Centers for Disease Control and Prevention (CDC): Protects public health and safety through disease control, health promotion, and prevention efforts.

   • MMWR (Morbidity and Mortality Weekly Report): A publication by the CDC that provides vital health information.

3. Role of the NIH:

   • National Institutes of Health (NIH): Conducts medical research and funds studies to enhance health and understand diseases.

Chapters 4, 5, and 6: Epidemiology

1. Definition of Epidemiology and its Role:

   • Epidemiology is the study of how diseases affect the health of populations. It helps identify risk factors, guide public health interventions, and improve health outcomes.

2. Endemic vs. Epidemic:

   • Endemic: The constant presence of a disease within a certain geographic area (e.g., malaria in certain parts of Africa).

   • Epidemic: A sudden increase in the number of cases of a disease above what is normally expected in that population.

3. Who, When, and Where:

   • Key questions in epidemiology that help define the characteristics of diseases in populations.

4. Notifiable Diseases:

   • Diseases that must be reported to government authorities when diagnosed (e.g., tuberculosis, measles).

5. John Snow:

   • Considered the father of modern epidemiology; famously mapped cholera cases in London and identified contaminated water as the source of an outbreak.

6. PAR (Population Attributable Risk):

   • The proportion of disease cases in the population that can be attributed to a specific risk factor.

7. Incidence vs. Prevalence:

   • Incidence: The number of new cases of a disease in a specific time period.

   • Prevalence: The total number of existing cases at a given time.

8. Distribution of Disease:

   • Refers to the analysis of the patterns and causes of health conditions in populations.

9. Kinds of Epidemiological Studies:

   • Intervention Studies: Test the effectiveness of an intervention (e.g., randomized controlled trials).

   • Cohort Studies: Follow a group over time to assess the impact of exposures on outcomes.

   • Case-Control Studies: Compare individuals with a disease to those without, assessing past exposures.

10. Odds Ratio (OR):

    • A measure of association between exposure and an outcome. OR > 1 indicates higher odds of disease with exposure, OR < 1 indicates lower odds.

11. Why is it Hard to Study Humans?

    • Ethical considerations, variability in human behavior, confounding variables, and long time frames required for studies.

12. Conflicts of Interest in Drug Trials:

    • Potential biases in research due to financial or personal interests of researchers or sponsors that may affect the integrity of study results.

Practice Questions:

1. Define the difference between incidence and prevalence and provide examples of each.

2. Describe the roles of the CDC and NIH in public health.

3. Discuss the implications of John Snow's work for modern epidemiology.

4. Why are some diseases classified as notifiable, and what is the purpose of this classification?