Gholamrezanezhad, at the University of Southern California in Los Angeles, and his team started tracking patients in January using computed tomography (CT) scanning to study their lungs. They followed up on 33 of them more than a month later, and their as-yet-unpublished data suggest that more than one-third had tissue death that has led to visible scars. The team plans to follow the group for several years.
These patients are likely to represent the worst-case scenario. Because most infected people do not end up in hospital, Gholamrezanezhad says the overall rate of such intermediate-term lung damage is likely to be much lower — his best guess is that it is less than 10%. Nevertheless, given that 28.2 million people are known to have been infected so far, and that the lungs are just one of the places that clinicians have detected damage, even that low percentage implies that hundreds of thousands of people are experiencing lasting health consequences.
Doctors are now concerned that the pandemic will lead to a significant surge of people battling lasting illnesses and disabilities. Because the disease is so new, no one knows yet what the long-term impacts will be. Some of the damage is likely to be a side effect of intensive treatments such as intubation, whereas other lingering problems could be caused by the virus itself. But preliminary studies and existing research into other coronaviruses suggest that the virus can injure multiple organs and cause some surprising symptoms.