SCIENTISTS have had eyes on Sars-CoV-2, the virus that causes Covid-19, since the beginning of this pandemic. They can see it is evolving, but it is happening at a glacial pace compared with two other viruses with pandemic potential: those that cause flu and Aids. That is good news for efforts to develop vaccines and treatments, but scientists remain wary that anything could still happen…

This article first appeared in The Guardian on 18 September 2020. To continue reading, click here.