Impact of Previous Coronavirus Disease 2019 on Immune Response after a Single Dose of BNT162b2 Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine - Velasco M; Galán MI; Casas ML; Pérez-Fernández E; Martínez-Ponce D; González-Piñeiro B; Castilla V; Guijarro C; Algora Weber A; Alonso Punter JC; Bonilla Zafra G; Bueno Campaña MªM; et al. (Open Forum Infectious Diseases, 2021)