Public Health Practice

History of Governmental Public Health

Public health practice in the United States has evolved over centuries, focusing on the prevention of disease and promotion of health at the population level.

• Early 20th Century: Establishment of full-time public health officers, especially in large cities like NYC.

• 1918-1940s: Epidemics (e.g., typhoid fever) led to the creation of local health departments.

• 1960s: Expansion of social programs (e.g., Medicare, Medicaid) and more coordinated health care.

• National Health Objectives: Initiated in 1979 with "Healthy People" to set measurable health goals for the nation.

Healthy People Initiatives

• Healthy People 1990, 2000, 2010: Set national objectives to improve health, increase lifespan, and reduce health disparities.

• 2010: Emphasized eliminating health disparities and improving quality of life.

Three Core Functions of Public Health

• Assessment: Collecting, assessing, and analyzing health data (e.g., morbidity, mortality, communicable diseases).

• Policy Development: Creating policies based on scientific knowledge and health assessments.

• Assurance: Ensuring services are provided to achieve health goals (e.g., health education, regulation, personal health services).

Public Health Infrastructure

Levels of Public Health

• International: WHO, UNICEF

• Federal: U.S. Department of Health and Human Services (HHS), CDC, FDA, EPA

• State: States have primary responsibility for public health within their borders.

• Local: Local health departments implement programs and services.

Types of Local Health Departments (NJ Example)

• Municipal Health Departments: Serve individual towns or cities.

• Regional Health Commissions: Serve multiple municipalities.

• County Health Departments: Serve entire counties.

Key Differences

• Municipal: Serve a single town/city.

• Regional: Serve multiple towns, often with shared resources.

• County: Serve all municipalities within a county.

Food Safety

Statistics and Impact

Foodborne illnesses are a significant public health concern, causing hospitalizations and deaths annually.

• ~325,000 hospitalizations per year in the U.S.

• ~5,000 deaths per year (Salmonella, E. coli, etc.)

Reasons for Concern

• Globalization of food supply

• Changes in food production and distribution

• Emergence of antibiotic-resistant bacteria

• Human demographics and behavior

Types of Food Contamination

• Physical: Foreign objects (e.g., glass, metal, hair)

• Chemical: Pesticides, cleaning agents, food additives

• Biological: Bacteria (e.g., Salmonella, E. coli), viruses, parasites

Nature of Bacteria (FAT TOM)

Bacterial growth in food is influenced by several factors, summarized by the acronym FAT TOM:

• Food: High-protein foods support growth

• Acidity: pH 4.5 or above allows growth

• Time: Bacteria multiply rapidly at room temperature

• Temperature: Danger zone is 41°F to 135°F

• Oxygen: Some bacteria require oxygen, others do not

• Moisture: Water activity above 0.85 supports growth

Common Foodborne Bacteria

Temperature and Food Safety

• Danger Zone: 41°F to 135°F (bacteria multiply rapidly)

• Cooking Temperatures: Poultry: 165°F, Ground beef: 155°F, Fish: 145°F

• Cooling: Food must be cooled from 135°F to 70°F within 2 hours, then to 41°F within 4 hours

Sanitization

• Chemical: Chlorine, quaternary ammonium

• Manual: Wash, rinse, sanitize

HACCP (Hazard Analysis Critical Control Point)

HACCP is a systematic approach to food safety, focusing on identifying and controlling hazards at critical points in the food production process.

1. Identify hazards

2. Determine critical control points (CCPs)

3. Establish critical limits

4. Monitor CCPs

5. Take corrective actions

6. Verify system works

7. Keep records

Water and Wastewater

Hydrologic Cycle

The hydrologic cycle describes the continuous movement of water on, above, and below the surface of the Earth.

• Evaporation, condensation, precipitation, infiltration, runoff

Uses of Water

• Drinking, cooking, cleaning, recreation, agriculture, industry

Well Water and Groundwater

• Types of wells: dug, drilled, jetted

• Groundwater contamination: septic systems, chemicals, poor land management

Septic Systems

• Septic tank separates solids and liquids, leach field disperses liquid

• Improperly managed systems can contaminate groundwater

Causes of Illness from Waterborne Exposures

• Bacteria: Cholera, E. coli

• Viruses: Hepatitis A, Norovirus

• Protozoa: Giardia, Cryptosporidium

• Chemicals: Pesticides, heavy metals

Environmental Health

Lead and Radon

• Lead: Found in gasoline, pipes, batteries; causes neurological and developmental problems

• Radon: Radioactive gas, #2 cause of lung cancer in the US

Air Pollution

• Sources: Industry, vehicles, power plants

• Effects: Respiratory and cardiovascular diseases, increased mortality

Acid Rain and Deposition

• Caused by emissions of SO2 and NOx from burning fossil fuels

• Effects: Acidification of lakes/streams, damage to forests and buildings

Global Warming and Climate Change

• Greenhouse gases: CO2, methane, nitrous oxide

• Effects: Rising temperatures, altered weather patterns, spread of tropical diseases

Urbanization

• Concentration of people can improve efficiency but also leads to sanitation and pollution challenges

Additional info: These notes expand on the original content by providing definitions, examples, and context for key public and environmental health concepts relevant to a Personal Health course.