(GH002) Global Health Introduction

Global Health Introduction

The presentation introduces global health, explains why health problems cross borders, and highlights approaches, achievements, and continuing challenges. Its central message is that global health depends on evidence-informed public health practice, attention to inequities, and collaboration across countries and sectors.

What Global Health Means—and Why It Matters

The Institute of Medicine defines global health as health problems and concerns that cross national boundaries and may be best addressed through cooperative action.

The presentation argues that health in other countries affects everyone because:

• Travel and global connectedness allow diseases to spread across borders. Examples include influenza, Ebola, measles, Zika, and COVID-19.
• Disease can destabilize societies, affecting families, communities, national security, and freedom.
• There are ethical responsibilities: preventable illness and death, malnutrition, and lack of access to care can harm people’s lives and perpetuate poverty.

Studying global health can provide lessons that improve health in other countries and in one’s own community.

Surveillance and Assessment Inform Public Health Action

International surveillance helps public health agencies anticipate outbreaks and prepare responses. Program assessment helps identify effective or promising practices and track progress toward health goals.

Examples discussed include the Ebola outbreak in West Africa, measles outbreaks, Zika, and COVID-19.

Examples of Public Health Best Practices

National Immunization Days in Bangladesh

In 1995, Bangladesh held two National Immunization Days as part of its effort to eradicate polio. Government agencies, media, voluntary organizations, and individual volunteers worked together to vaccinate children.

The presentation reports that:

• 88% of children under five received at least one oral polio vaccine dose.
• 67% received two doses.
• 68% received vitamin A.

The example illustrates how coordinated, concentrated campaigns can raise immunization coverage. Bangladesh was reported to have eradicated polio in 2006.

Smallpox Eradication and Ring Vaccination

The last naturally occurring smallpox case was reported in Somalia in 1977. The World Health Assembly certified eradication in 1980. The presentation identifies ring vaccination—not mass vaccination alone—as an important final strategy for stopping transmission.

The ring vaccination process described in the presentation is:

1. Isolate confirmed and suspected cases to prevent further exposure.
2. Identify, vaccinate, and monitor significant contacts of cases—the first ring. Monitor contacts for illness and isolate anyone who develops the disease.
3. Vaccinate household contacts of those contacts—the second ring, providing an additional safeguard.

Smallpox was transmitted between people, primarily through respiratory droplets during close contact. The presentation also reviews the disease’s course, severity, and historical vaccine, noting that vaccination reduced the risk of illness or severe disease.

Progress and Ongoing Challenges

Progress described in the presentation includes:

• A decline in the global death rate among children under five since 1950, alongside increased life expectancy in developing countries.
• The eradication of smallpox and substantial progress toward eliminating polio.
• Reduced measles deaths and decreases in Guinea worm disease, linked in the presentation to clean-water programs.

Challenges remain, including deaths among newborns, children, and women in childbirth; tuberculosis; and the spread of diseases such as West Nile virus and dengue.

Dengue Example

Dengue is transmitted mainly by Aedes mosquitoes and has multiple viral serotypes. The presentation describes flu-like symptoms and the risk of severe dengue, including hemorrhage and shock, after infection with a different serotype.

It also discusses a dengue vaccine and its use for a specified group with laboratory evidence of previous infection who live in endemic areas. These details are presented as part of the lecture’s account of vaccine guidance.

Health Disparities

The lecture highlights disparities in life expectancy, access to health services, and outcomes such as child mortality, food security, and maternal health. It argues that these gaps are not explained by biological or genetic differences, but are strongly shaped by public health capacity, access to medical technology and personnel, and the distribution of resources.

Examples include:

• Differences in life expectancy between countries.
• Unequal risks of infant and child mortality within and between countries.
• Differences in access to skilled birth attendants and maternal health outcomes.
• Food insecurity and malnutrition, especially among children in lower-income regions.
• Health outcome gaps associated with income, social status, ethnicity, gender, disability, and sexual orientation.

The presentation also emphasizes the value of public health interventions. It cites an estimate that public health measures accounted for most of the increase in U.S. life expectancy during the twentieth century, highlighting achievements such as vaccination, sanitation, safer workplaces and food, and tobacco control.

Health and Development

Health and economic development are closely linked:

• Poor health can reduce productivity, weaken institutions, discourage investment, and contribute to insecurity.
• Poor health among mothers can affect babies. Illness and malnutrition can limit children’s development, school participation, and later economic opportunities.
• These effects can reinforce poverty across generations.

Using Maslow’s hierarchy of needs, the presentation argues that development plans should first assess and address major unmet needs—such as food, water, shelter, safety, belonging, and respect—before expecting sustained progress toward higher-level growth and self-actualization.

Collaboration and Public Health’s Role

No single person, organization, or country can solve global health problems alone. The presentation calls for collaboration among governments, nonprofit and faith-based groups, businesses, educational and health-care organizations, and rural, urban, cultural, and community groups.

Public health is described as well positioned to convene and facilitate such partnerships at local, state, and international levels.

Definitions and Closing Ideas

• The World Health Organization (WHO) defines health as complete physical, mental, and social well-being—not merely the absence of disease or infirmity.
• C. E. A. Winslow’s definition of public health emphasizes organized community efforts to prevent disease, prolong life, promote health, control infections, educate people, provide medical and nursing services, and support adequate living conditions.
• The lecture distinguishes public health’s focus on populations from clinical medicine’s focus on individuals, while stressing the need for integration and partnership between them.
• Merson et al. define global health as applying public health principles to health challenges that cross national boundaries, as well as to the global and local forces affecting those challenges.

The session closes by identifying core global health topics for further study: determinants of health, measuring health status, culture, the global burden of disease, risk factors, demographic and epidemiologic transitions, and health systems.

Speakers and Sources Featured

Speaker: One unnamed presenter delivered the lecture.

Sources and organizations cited or referenced:

• United States Institute of Medicine
• World Health Organization (WHO), including the World Health Assembly
• Centers for Disease Control and Prevention (CDC)
• CDC Advisory Committee on Immunization Practices (ACIP)
• C. E. A. Winslow
• Merson et al.
• European Parliament
• Sanofi Pasteur, in relation to the dengue vaccine discussed in the lecture
• Public health surveillance and program-assessment examples and figures attributed in the presentation to various reports; specific report titles are not provided in the subtitles.