How did SARS-CoV-2 go viral?

SARS-CoV-2 has been hugely successful compared to its predecessor; new research investigates why. A team from Duke University (NC, USA) has shed light on SARS-CoV-2 evolution, revealing the ‘silent’ mutations that enabled SARS-CoV-2 to ‘go viral’. Their results could explain how it has vastly outpaced the SARS epidemic of 2003. During the original SARS outbreak shedding began 2—10 days after symptom onset, making it easier to get under control. It is therefore reasonable to assume that mutations improving viral transmission would be favored by natural selection. With previous research highlighting the spike protein gene as a target of natural selection,...