9.5 Diseases and Vaccines

Disease spreads faster with globalization

Increased travel, trade, and urbanization after 1900 accelerated the global spread of infectious diseases. The 1918 influenza pandemic (Spanish Flu) killed an estimated 50-100 million people worldwide, spreading rapidly via troop movements during WWI. Later, HIV/AIDS emerged in the late 20th century as a global pandemic, devastating populations especially in sub-Saharan Africa, revealing gaps in healthcare access and funding.

Medical advances change global health

Vaccines and medical breakthroughs dramatically reduced deaths from diseases like smallpox, polio, and measles. The World Health Organization (WHO), founded in 1948, coordinated global efforts such as the smallpox eradication campaign (declared eradicated in 1980). These successes showed how international cooperation could combat disease, though access to vaccines remained unequal between wealthy and developing nations.

Inequality shapes health outcomes

Disease impact often reflected economic inequality: poorer nations lacked resources for prevention, treatment, and vaccine distribution. Global health organizations (WHO, UNICEF, NGOs) worked to close these gaps, but disparities persisted, as seen with HIV/AIDS treatment access and, more recently, COVID-19 vaccine distribution — highlighting ongoing tensions between globalization's benefits and unequal outcomes.

Key terms

1918 Influenza Pandemic

A deadly global flu outbreak spread by WWI troop movements; killed an estimated 50-100 million people.

World Health Organization (WHO)

Founded in 1948; coordinates international efforts on disease prevention, vaccination, and health crises.

Smallpox eradication (1980)

Result of a global WHO vaccination campaign; smallpox is the only disease eradicated worldwide.

HIV/AIDS epidemic

Global pandemic emerging in the late 20th century, disproportionately affecting sub-Saharan Africa due to limited healthcare access.

Global health inequality

Unequal access to vaccines and medical resources between wealthy and developing nations, shaped by economic disparities.

Try an AP-style question

The 1918 influenza pandemic spread rapidly because of…

1. information shared over the internet
2. passengers traveling by jet airliner
3. tensions of the early Cold War
4. troop movements at the end of WWI