Why should we test all travellers from China?

What’s the point in asking people flying in from China to present a negative Covid test? Rishi Sunak has stepped in to order this, but he hasn’t quite explained why this is necessary or how it would help. Covid is still widespread worldwide but British resistance (through exposure and vaccination) is such that the virus is not seen as a threat to the NHS (collapsing for other reasons) or public health.

Data in Singapore from travellers in China confirms Beijing’s evidence that the variants it’s dealing with are BA.5.2 and BF.7 which have been in the UK for months. They can cause mayhem in an unexposed, badly-vaccinated country like China – but not to us. There’s no reason, yet, to suspect the Chinese are hiding a dodgy variant and if they were, the rest of Asia would find out quickly. So why, even in theory, would it be a problem if people flew in from China or anywhere else with a virus that is now ubiquitous?

Demanding a negative test to those coming in from China is pretty low on a travel disruption scale that, once, went up to two weeks confinement in a hotel.