It is now five years since clinicians in Wuhan, China, first encountered covid-19 cases in December 2019. Hindsight makes it even clearer how the battle against the disease wasn’t just a fight against a virus, but also a struggle against the political suppression of scientific evidence.

This isn’t a new phenomenon. During the SARS outbreak, which started in China’s Guangdong province in November 2002, local authorities initially restricted the release of information and downplayed the severity of the outbreak. In the ensuing months, the virus spread in China and overseas unhindered.

China vowed to learn lessons from SARS, and established…