“None of these has convinced me that they have a smoking gun for why one particular sequence of SARS-CoV-2 is more successful than any other,” Houldcroft says.
Finding a smoking gun is not a priority right now, according to the experts I spoke with. Gralinski, for example, is focused on testing vaccines and drugs. She wouldn’t start checking whether different mutations affect the virus’s behavior until next year, “when the urgency has waned,” she says. Grubaugh agrees: Studies of viral evolution are the backbone of his career, but he says they “wouldn’t change the public-health picture.” To control the coronavirus, countries need to test widely, isolate infected people, trace their contacts, and use social-distancing measures when other options fail. “Identifying a mutation that does something different doesn’t really change our response,” Grubaugh says. “It just creates a diversion from what we need to be focusing on.”