• Obesity or being overweight (i.e., body mass index [BMI] >25 kg/m 2 ) • Current smoker • Chronic kidney disease • Diabetes • Immunosuppressive disease or immunosuppressive treatment • Cardiovascular disease (including congenital heart disease) or hypertension • Chronic lung disease (i.e., chronic obstructive pulmonary disease, asthma [moderate-to- severe], interstitial lung disease, cystic fibrosis, and pulmonary hypertension) • Sickle cell disease • Neurodevelopmental disorders (i.e., cerebral palsy, Down's syndrome) or other conditions that confer medical complexity (i.e., genetic or metabolic syndromes and severe congenital anomalies) • Active cancer • Medical-related technological dependence not related to COVID-19 (i.e.,气管切开术,胃造口术或正压通风)