The first author of the study was Suchitra Rao, MD, University of Colorado School of Medicine and Colorado Children's Hospital. Their findings have so far uncovered a few clues to long COVID risk. For instance, about 45% of the children who developed long COVID experienced COVID-19 symptoms rather than symptomless infections (15%). Other factors include older age, more severe initial COVID-19 infection, the number of different organ systems initially affected, underlying medical conditions and higher weight.