How China’s Sinovac compares with BioNTech’s mRNA vaccine

In much of the world, hard lockdowns to curb transmission of SARS-CoV-2 seem a thing of the past. Not in China. On April 19th, Shanghai entered its third week of a strict lockdown, having registered 19,442 new transmissions the day before (ten deaths have been recorded in the current wave). The disruptions clearly have a huge human and economic cost, but the government appears to have no clear plan B. The main problem is that the elderly in China are insufficiently vaccinated. But it does not help that at one or two doses, at least one of its vaccines is less effective than an mRNA shot widely available elsewhere.