Epidemiology_ Basic Science of Public Health_JS_02.10.25 (1)

Introduction to Community and Public Health

• Chapter 2: Descriptive Epidemiology in Community and Public Health

• Epidemiology: Basic Science of Public Health

About Me

• Julie Sanem, PhD (she/her)

• Teaching: PUBH 3003

• Position: Research Center Manager, Cannabis Research Center, School of Public Health since February 2024

  • Focus: Important research questions regarding cannabis and health

• Previous Role: Director of Health Promotion at Boynton Health

  • Focus: Substance Use Prevention, Risk Reduction, Recovery

• Education:

  • Ph.D. in Epidemiology (2017)

  • MPH in Community Health Education (2007)

Objectives

• Define epidemiology

• Understand the role of John Snow in epidemiology

• Use common measures of disease occurrence to solve public health problems

• Explain the purpose of measuring health and the application of data

• Define the terms endemic, epidemic, and pandemic

What is Epidemiology?

• The science focused on the distribution of health-related conditions, behaviors, and factors over time, place, and among persons

• Helps identify antecedents and causes of health conditions to plan interventions for prevention and control

Responsibilities of Epidemiologists

• Collect and analyze vital records (births, deaths)

• Gather morbidity data (from health records)

• Identify disease risks and public health issues within a population

• Monitor diseases within communities

• Investigate outbreaks to control or prevent epidemics

• Design and implement surveillance systems and health screenings

• Evaluate health programs

• Provide data for planning and decision-making

Reportable Diseases (Minnesota Department of Health)

• Immediate telephone report required for diseases such as:

  • Anthrax, Botulism, Cholera, etc.

• Other diseases reportable within one working day include:

  • Babesiosis, Blastomycosis, COVID-19, and more

• Detailed procedures for reporting and submission of clinical materials

Purpose of Population Health Information

• Understanding community health status:

  • Current health issues

  • Changes over time

  • Influencing factors

• Application of information for:

  • Identifying needs

  • Decision making about health investments

  • Assessing health program performance

  • Developing and evaluating public health policy

Population Characteristics in Measuring Disease Frequency

• Analyzing data for subgroups:

  • Age, sex, race/ethnicity, location, and community membership types

Descriptive Epidemiology

• Patterns of disease occurrence:

  • Who is affected (demographics, behaviors)

  • When they are affected (time factors)

  • Where the disease occurs (geographical considerations)

John Snow and His Contribution

• Recognized as the "father" of epidemiology

• Challenged the miasma theory during the cholera outbreak in London (1854)

  • Noted high mortality in poorer districts

Measures of Disease Occurrence

• Incidence: New cases within a defined population over a specific time

• Prevalence: Total cases (new and existing) at a certain point in time

Disease Proportions

• Incidence Proportion:

  • Formula: (# of new cases / population at risk)

• Prevalence Proportion:

  • Formula: (# of cases / total population)

• Includes measures like mortality rates, birth rates, etc.

Case Studies and Examples

• Incident Cases example (college study) shows methods to determine cases over specific timelines

• Prevalent Cases example mirrors the methodology but focuses on total cases diagnosed

• Illustrations of incidence and prevalence proportions through university data

Important Terms

• Endemic: A disease consistently found in a particular area

• Epidemic: A sudden increase above normal expectations for a locality

• Pandemic: A global epidemic affecting multiple countries or populations

Prevention Paradox

• Refers to prevention measures generating significant community benefits with relatively little impact on individuals

  • Examples include seat belt laws, smoking bans, and immunizations

Rose’s Theorem

• Highlights that a large number of people exposed to low risk can create more cases than a small number exposed to high risk

Levels of Prevention

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

• Secondary Prevention: Identifying and treating diseases early (e.g., screening tests)

• Tertiary Prevention: Managing disease to reduce complications (e.g., rehabilitation)

Social and Behavioral Epidemiology

• Addresses how social factors influence diseases, including poverty and structural racism

Epidemiological Triad

• Agent: Factors that can cause health conditions

• Host: Organisms affected by agents

• Environment: Conditions affecting the interactions between agents and hosts

Drug-related Issues

• Internal and external factors affecting host (individual) conditions in drug use situations

Public Health Examples in Daily Life

• Encourage observation of epidemiology in media, health programs, etc.

References

• List of resources including podcasts, books, and articles related to public health and epidemiology.