Smallpox killed hundreds of millions of people over the centuries and was declared eradicated in 1980. William Foege, an American epidemiologist, helped shift the global campaign toward surveillance and containment. Instead of trying to vaccinate every person, teams searched for each new case, identified everyone who had been in contact with it, and vaccinated the ring of people around that case. This approach stopped chains of transmission far more efficiently than mass vaccination alone in many places. It worked because the virus spreads only between people and has no animal reservoir. His strategy is a model for how targeted action can outperform blanket effort.

Hampi is a UNESCO World Heritage Site in Karnataka, India, with more than 1,600 surviving remains spread over 4,100 hectares. It was the capital of the Vijayanagara Empire from 1336 to 1565. Travellers from Persia and Portugal described it as a prosperous, wealthy and grand city with temples, markets and farms along the Tungabhadra River. By 1500 it was estimated to be the world's second-largest city after Beijing, and probably India's richest at the time. In 1565 a coalition of Muslim sultanates defeated the Vijayanagara Empire, its capital was conquered and destroyed, and the city was left in ruins. Hampi remains a religious centre, with the active Virupaksha Temple at its heart.