The Chinese Spring Festival marks the beginning of a new year in the lunar calendar. It is known as China’s most celebrated holiday and a time for family reunification. The annual peak in travel associated with the lunar new year is the ultimate stress test for China’s transportation system. During chunyun (春运) translated as Spring Festival Transportation, every year up to 3 billion trips are made within a period of about 40 days1 domestically and to international destinations (compared to 116 million Americans traveling during the Christmas and New Year’s holiday in 20192). With passenger volumes rising annually, chunyun is holding on to its title as the world’s most voluminous human migration. This year’s Chinese Spring Festival Travel Rush, however, coincided with a particular challenge as it came at a time when China faced a major public health crisis with severe societal ramifications: The outbreak of the COVID-19 epidemic, caused by the virus SARS-CoV-2, which is thought to have originated in Wuhan, a hub in China’s transport and logistics network, and had reached pandemic proportions only weeks later. In the first days of the Spring Festival 20203 before initial transport restrictions were put in place to stall the spread…