The World Health Organization has walked back a top official’s claim that asymptomatic people rarely spread the coronavirus to others. The WHO’s confused messaging on the topic drew criticism from public health officials. The Harvard Global Health Institute said, “In fact, some evidence suggests that people may be most infectious in the days before they become symptomatic — that is, in the presymptomatic phase when they feel well, have no symptoms, but may be shedding substantial amounts of virus.” Meanwhile, two new papers published in the journal Nature find coronavirus lockdowns saved millions of lives and averted tens of millions of infections worldwide. UC Berkeley researcher Solomon Hsiang co-authored one of the reports.

Solomon Hsiang: “Never in human history have so many people around the world come together, coordinated their actions and worked to save so many lives in such a short period of time.”