Influenza B Yamagata, one of the two lineages of seasonal influenza B, has probably gone extinct since 2020. Flu viruses usually circulate every year, but this lineage was last detected in early 2020 and has not been seen since. Scientists think the COVID-19 pandemic, with masks, distancing and reduced travel, cut transmission so sharply that the virus could not find enough hosts to persist. The lineage had been included in seasonal flu vaccines for years, so its disappearance has led health authorities to drop it from some formulations. Viral lineages do vanish occasionally, but it is rare for one to disappear within a few years. The case shows that public health measures can change which pathogens exist, not just how many people fall ill.

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.