Public Health Exam 2

Module 14 to Module 19: Non-Communicable Diseases (NCDs), Communicable Diseases, US Health Systems, Nutritions

What are non-communicable diseases (NCDs)?

Chronic diseases of long duration caused by genetic, physiological, environmental, and behavioral factors that are not contagious and rarely fully cured

What are major characteristics of NCDs?

Complex causes, multiple risk factors, long pre-clinical phases, non-contagious origin, prolonged illness, and often functional impairment or disability.

What are the four main categories of NCDs globally?

Cardiovascular diseases, cancers, chronic respiratory diseases, and diabetes

• also: arthritis/musculoskeletal diseases, alzheimer’s/dementias, mental health disorders

How significant are NCDs globally?

They cause about 74% (3/4) of deaths worldwide (~41 million annually) and are major causes of preventable disability

What is a risk factor?

A behavior, exposure, or hereditary trait that increases the likelihood of developing a disease or health condition

What are the four major modifiable risk factors for NCDs?

Physical inactivity, tobacco use, harmful alcohol use, and unhealthy diet

What is a modifiable risk factor?

A behavioral risk factor that can be reduced or controlled by intervention, thereby reducing the probability of disease.

What are examples of non-modifiable risk factors?

Age, biological sex, race/ethnicity, and genetic/family history.

• cannot be targeted by intervention

Why is targeting risk factors important in NCD prevention?

Because NCDs develop over long periods and result from multiple exposures, so prevention focuses on reducing risk factors.

Why are NCD risk factors called “shared”?

The same behaviors (e.g., smoking, poor diet) increase risk for multiple diseases like CVD, diabetes, and cancer.

What is cardiovascular disease (CVD)?

A group of disorders of the heart and blood vessels, including coronary heart disease, stroke, and peripheral artery disease

• e.g, coronary heart disease, cerebrovascular disease (strokes), peripheral arterial disease, etc.

Why is CVD especially important among NCDs?

It is the #1 cause of death worldwide, with most deaths from heart attack and stroke

• many occur in low- and middle- income countries

• non-modifiable risk: family history, race, age, gender

• modifiable risk: physical activity, diet, weight, etc.

How do social determinants influence NCD risk?

Factors like poverty, stress, discrimination, and pollution affect behaviors and biological processes that increase disease risk.

What is cancer?

A group of diseases involving rapid growth of abnormal cells that can invade nearby tissues and spread (metastasize).

What causes cancer?

Mutations due to inherited factors, lifestyle behaviors (e.g., smoking), environmental exposures, infections, or random cellular errors.

• internal: inherited mutations, immune conditions

• external: lifestyle factors

How can cancer risk be reduced?

Through lifestyle changes such as avoiding tobacco, improving diet, increasing physical activity, limiting alcohol, and reducing exposure to carcinogens

Why is screening important for cancer control?

When prevention is not possible, early detection through screening improves treatment outcomes and survival

What are the two types of screening?

Population-based screening and high risk-screening.

What is population based screening?

Targets large demographic groups

• e.g, womens age 40-79 for breast cancer

What is high-risk screening?

recommendations apply to those at elevated risk

• e.g, family history of colorectal cancers

What is considered a case?

an individual with a particular disease

What is an infectious disease?

A disease caused by pathogenic microorganisms such as bacteria, viruses, parasites, or fungi.

What is a communicable disease?

An infectious disease that can be transmitted from human to human, animal to human, or animal to animal.

What are zoonotic diseases?

Infectious diseases that originate in animals but can be transmitted to humans.

What is the latent period?

time interval between infection and infectiousness

• varies across communicable disease

What is the incubation period?

time interval between infection and the first signs and symptoms of disease

What are the three components of the epidemiological triad?

Agent (pathogen), host (susceptible individual), and environment (conditions that allow transmission).

What is a vector?

An organism that transmits a pathogen between hosts without becoming diseased itself.

What are the main types of infectious agents?

Bacteria, viruses, and parasites (also fungi)

What are bacteria?

one-celled microorganism that grows and reproduces outside the body

• tuberculosis, cholera, tetanus, syphilis, staphylococci

What are viruses?

a pathogen that is not capable of independent metabolism and can reproduce only inside living cells

• e.g, smallpox, hepatitis, measles, rabies, HIV

What are parasites?

an organism that lives off another organism (host) but does not contribute to the welfare of the host

• e.g, malaria, tapeworms, hookworms, pinworms

What are the main steps in the chain of infection?

Infectious agent → reservoir → portal of exit → mode of transmission → portal of entry → susceptible host.

What are common modes of transmission?

Direct contact, indirect contact, droplet, airborne, fecal-oral, and vector-borne transmission.

• think of the flu - droplet contact, indirect contact (24 hrs) and direct physical contact.

What is the Portal of Entry?

Enters through a portal of entry to infect a susceptible host

• ears, broken skin, nose, mouth, conjunctiva of eye, insect bite

What is the Portal of Exit?

Agent leaves the reservoir through this portal

• Ear (earwax), broken skin (blood), eyes (tears), nose (secretions), mouth (saliva, sputum), urethra (urine), anus (feces), etc.

What is the reservoir?

Habitat in which agent lives, grows, multiplies

Why are communicable diseases a major public health issue?

They disproportionately affect low-income populations, cause economic burden, and many are preventable.

What are three major infectious diseases contributing to global burden?

HIV, tuberculosis, and malaria.

What are the WHO’s Three Categories?

1. Disease that cause high level of mortality

2. Disease that cause high level of disability

3. Disease that can spread unpredictably and have serious global repercussion

How can the chain of infection be broken?

Treat the pathogen, eliminate reservoirs, prevent transmission (handwashing, isolation), and increase host immunity through vaccination

What is the difference between control, elimination, and eradication?

Control = reduce disease to acceptable levels

Elimination = reduce incidence to zero in a specific area

Eradication = permanent global removal of disease.

What are emerging infectious diseases?

Diseases whose incidence has recently increased or threatens to increase due to ecological change, globalization, or microbial evolution.

What are neglected tropical diseases?

Communicable diseases common in tropical regions that primarily affect populations living in poverty.

What are STIs?

Infections transmitted through sexual contact between individuals

How are foodborne and waterborne diseases transmitted?

Mainly through ingestion of contaminated food or water via fecal-oral transmission.

What are healthcare-associated infections?

Infections acquired while receiving medical treatment, often related to procedures or medical devices.

• surgical site infections, through devices

• One out of every 25 hospitalized patients

• Mostly preventable but very costly, unjust

What should health systems provide?

Prevention, diagnosis, treatment, and rehabilitation services while protecting individuals from catastrophic health costs

What are the six WHO health system building blocks?

1. Service delivery

2. Health workforce

3. Health information systems

4. Access to essential medicines

5. Financing, and

6. Leadership/Governance.

What outcomes should strong health systems achieve?

• Improved health and equity,

• Responsiveness,

• Social/financial risk protection, and

• Improved efficiency

What changes health goals / outcomes?

Access Coverage and Quality Safety

What is universal health coverage?

Ensuring all people can access needed quality health services without financial hardship.

What elements must work together to achieve UHC?

Service delivery, financing, and governance systems.

What does governance include in health systems?

Regulation of services, taxation policies, facility ownership, and workforce regulation.

How does health system financing typically work?

Funds are collected (taxes, employment contributions, out-of-pocket) → pooled → then spent on services.

What factors are used to evaluate health systems?

Population and clinical health outcomes, equity, responsiveness, fair financing, and efficiency.

What factors are included in Human and Physical Resources?

1. Service delivery

2. Workforce

3. Information system and

4. Access to medicines

What are examples of universal coverage models?

• Single payer (e.g., UK NHS)

• Universal Mandate for coverage with multiple payers: (Germany)

• United States = Fragmented System of Coverage

What is Universal Health Coverage?

all people have access to the full range of quality health services they need, when and where they need them, without financial hardship

How is the US health system described?

A fragmented system with multiple coverage sources rather than a single universal system.

What are major ways people obtain insurance in the US?

Employer-sponsored insurance, individual plans, Medicare, Medicaid, or being uninsured.

Who qualifies for Medicare?

Primarily adults ≥65 years and individuals with permanent disabilities.

• “Cares’ for the elderly

How is Medicaid eligibility determined?

Based on income level (relative to federal poverty level) and category such as children, pregnant women, or frail elderly.

How is Medicaid funded?

Jointly by the federal government (at least half) and individual state governments.

When was the ACA passed and what was its goal?

Passed in 2010 to expand insurance coverage, improve quality, and reduce healthcare costs.

What did Medicaid expansion aim to do under ACA?

Extend coverage to low-income adults up to ~138% of the federal poverty level.

What is the Medicaid coverage gap?

n non-expansion states, some low-income adults earn too much for Medicaid but too little for marketplace subsidies

What are common barriers to care among uninsured adults?

Delayed care, lack of usual care source, and inability to afford medications or visits

How do uninsured individuals often obtain care?

Self-pay, community health centers, or emergency treatment under EMTALA law. (Slide page 48)

What was the One Big Beautiful Bill Act?

Presented as a major legislative proposal with provisions that could change eligibility, funding, and access to health insurance programs such as Medicaid and ACA marketplace coverage

What is nutrition?

The process by which the body takes in and uses food substances needed for growth, metabolism, and health.

What is the UNICEF Conceptual Framework?

Describes health outcomes or intermediates based off determinants of nutritional status

• immediate causes, underlying causes, basic causes

• inadequate education, child care, insufficient health services and household food security, etc.

What is malnutrition?

A condition resulting from deficiencies, excesses, or imbalances in energy or nutrient intake.

What are the main forms of malnutrition?

Undernutrition (wasting, stunting, underweight), micronutrient deficiencies, overweight, and obesity.

What is the difference between stunting and wasting?

Stunting = chronic poor nutrition leading to low height-for-age; wasting = acute weight loss or low weight-for-height.

What is the “double burden” of malnutrition?

The coexistence of undernutrition and overweight/obesity within populations or individuals.

What are micronutrients?

Vitamins and minerals needed in small amounts for normal physiological function.

What are macronutrients?

Nutrients required in large amounts for energy and body function: carbohydrates, proteins, and fats.

What is food security?

When all people have physical and economic access to sufficient, safe, and nutritious food at all times.

What factors contribute to food insecurity?

Poverty, conflict, climate change, economic instability, and poor food systems.

Why is malnutrition a major global health issue?

It contributes to child mortality, impaired development, increased infection risk, and chronic disease later in life.

What is the nutrition transition?

A shift from traditional diets to processed, high-calorie diets associated with urbanization and economic development.

How does diet influence NCD risk?

Poor diet increases risk for obesity, cardiovascular disease, diabetes, and some cancers.

Why is early nutrition critical?

It affects growth, cognitive development, immune function, and long-term disease risk.

What are key strategies to improve nutrition at the population level?

Food fortification, supplementation programs, breastfeeding promotion, and improving food systems.

How can policy influence nutrition?

Through food labeling laws, taxation/subsidies, school nutrition programs, and regulation of food marketing.

What is a sustainable diet?

A diet with low environmental impact that supports food security and health for present and future generations.

What are the nutrtional needs through the life cycle?

Pregnancy (300 cal surplus), infancy (breastfeeding and “window of opportunity”), Adolescence (iron, calcium, etc.), Adulthood & old age

What is inadequate dietary intake?

Dietary quality vs quantity, seasonality of foods, bioavailability of nutrients

• inadequate dietary intake weakens body and makes it more susceptible to infectio

What is low birthweight?

A newborn weight of < 2,500 g (5.5 lb) regardless of gestational age.

• Higher risk of infant mortality and infection.

What is the early initiation of breastfeeding?

putting baby to the breast for feeding within the first minutes/hours of life

What is the exclusive breastfeeding?

giving only breastmilk to an infant for the first six months of life

What is continued breastfeeding?

breastfeeding on demand (with introduction of appropriate complementary foods) until 12-24 months of life

What is acute malnutrition?

Being too thin for one’s height, measured by mid-upper arm circumference (MUAC)

What is severe acute malnutrition (SAM)?

serious, life-threatening condition with severe wasting (thinness) resulting from illness, lack of nutritious foods, &/other underlying causes

What is moderate acute malnutrition (MAM)?

the state of moderate wasting increasing susceptibility to life-threatening illness

What is the significance of PlumpyNut?

a ready-to-use therapeutic food (RUTF) used to treat severe acute malnutrition (SAM) in children, especially in low-resource or emergency settings.

What is food fortification?

The intentional addition of vitamins or minerals to foods to prevent or correct nutrient deficiencies in a population.