How the coronavirus kills people – and how to stop it

DEXAMETHASONE has become the first drug shown to lower the death rate from covid-19. The discovery of the benefits of this widely available steroid, which damps down an overactive immune system, was seen as a much-needed piece of good news. But we will need lots of other treatments to help us turn the tide of severe covid-19.

Many of the coronavirus drug trials so far have looked at antiviral medicines that may stop the virus from replicating. While some of these appear…