My wife met me off the overnight train from Beijing. ‘It’s been ages,’ she said. ‘Let’s go and have breakfast somewhere.’ How nice, I thought. But breakfast was slow – spun-out slow – and she kept looking at her watch. And when breakfast turned into a boat trip, and a boat trip became a shopping expedition, I began to tire. I was still wearing the clothes I’d slept in, and I hadn’t seen our three-year-old daughter for a week. Then the truth came out: I wasn’t allowed home until lunchtime. Liu Hong’s mother had read that the Sars virus can live for four hours on clothes and bags. I was lucky: a couple of weeks later it became clear that the virus can survive on surfaces for up to 24 hours.