The spread of swine flu, though less terrifying than first predicted, has generated all kinds of heavy-handed reactions around the world.

In China, the authorities quarantined for a week all those passengers who had arrived in Shanghai on the same flight as a Mexican infected with the flu. Hong Kong locked up about 300 people in a hotel because an infected Mexican man had stayed as a guest. And in the US, Joe Biden, the vice-president, shocked Americans by suggesting he would tell members of his family to avoid confined places, including aeroplanes and the subway.