It was early 2020, a week or two into Hilary Term, what everyone else calls Spring Term, but we at Oxford love our arcane traditions. I recall one of my graduate students, from China, coming to me ashen-faced at the end one of my lectures on the effects of bilingualism on the linguistic and cognitive development of young learners. "Please be careful," she said. "Have you heard about the disease. It's really scary. Please look after your family." Over the preceding Christmas break, news had started to filter through about a new form of flu that had spread rapidly from Wuhan in Eastern China to other parts of the country and was now starting to emerge in other parts of the world. We were starting to see desperate images of enforced quarantine, coerced separation of infected individuals from their loved ones, the rapid construction of temporary hospitals to house the unwell, and of course, school closures. It didn't look good. But I had seen similar outbreaks in the past. I had been working in Southeast Asia during the avian flu epidemic of 2003-04, and I was still there when swine flu broke out in 2009. Both were worrying, but neither had come to anything that could be classified as universally threatening. The school where I worked sent colleagues and children to be tested at the first sign of a tickly throat or stuffy nose, and a strict and regular cleaning and hand sanitising regime was implemented.