Evaluating the impact of sickle cell disease on COVID-19 susceptibility and severity: a retrospective cohort study based on electronic health record oleh Jiajun Luo, Jiajun Luo, Jiajun Luo, Johnny Powell, Sage Ross, Julie Johnson, Christopher O. Olopade, Jayant Pinto, Karen Kim, Karen Kim, Habibul Ahsan, Habibul Ahsan, Habibul Ahsan, Briseis Aschebrook-Kilfoy, Briseis Aschebrook-Kilfoy, Briseis Aschebrook-Kilfoy