These Covid-19 symptoms raise new questions

Two years ago, the calamitous first wave of the Covid-19 pandemic hit the US with unprecedented intensity. The depth of the terror can be difficult to recall and, thanks to advances in diagnosis, treatment and vaccination, is unlikely to recur. For scientists, however, it is crucial to revisit the dark time and rethink what happened by examining the almost endless data that was collected to try to better understand both the immediate and the long-term effects this disease has on the body.