Figure 1.

Workflow of the COVID-19 SMILE algorithm. Asymptomatic and apyretic screenees had to fill in a health questionnaire and to undergo rapid antigen nasopharyngeal swabbing and blood test. Those screenees who tested negative at the rapid antigenic swab were admitted and completed the lung cancer screening and prevention program interventions of the designed algorithm (carbon monoxide test, administration of antitobacco and antiinflammatory drugs, and ultra-low-dose CT scan). Ultra-low-dose CT scans were reviewed immediately to rule-out COVID-19 pneumonia-related findings. CO = carbon monoxide; SMILE = Screening and Multiple Intervention on Lung Epidemics; ULDCT = ultra-low-dose CT.