Dr Joseph Varon, 58, the chief medical officer at United Memorial Medical Center (UMMC), and a team of healthcare workers perform CPR on a COVID-19 patient at UMMC, during the coronavirus disease (COVID-19) outbreak, in Houston, Texas, US, July 17, 2020. Reuters

Biological signatures of
worst cases uncovered

Why do some people get severely sick with COVID-19, whereas others quickly recover?