Most covid-19 cases are caused by a particular type of variant, but do we need to worry every time a new one emerges? https://www.newscientist.com/article/2593098-does-each-new-covid-19-variant-pose-a-significant-threat/?utm_term=Autofeed&utm_campaign=echobox&utm_medium=social&utm_source=Twitter#Echobox=1792539722