Background Antigen testing offers rapid and inexpensive testing for SARS-CoV-2 but concerns regarding performance, especially sensitivity, remain. Limited data exists for use of antigen testing in asymptomatic patients; thus, performance and reliability of antigen testing remains unclear. Methods 148 symptomatic and 144 asymptomatic adults were included. A nasal swab was collected for testing by Quidel Sofia SARS IFA (Sofia) as point of care. A nasopharyngeal swab was also collected and transported to the laboratory for testing by Cepheid Xpert Xpress SARS-CoV-2/Flu/RSV RT-PCR (Cepheid). Results Overall, Sofia had good agreement with Cepheid (> 95%) in adults, however was less sensitive. Sofia had a sensitivity of 87.8% and 33.3% for symptomatic and asymptomatic patients, respectively. Among symptomatic patients, testing > 5 days post symptom onset resulted in lower sensitivity (82%) when compared with testing within 5 days of symptom onset (90%). Of the four Sofia false-negative results in the asymptomatic cohort, 50% went on to develop COVID-19 disease within 5 days of testing. Specificity in both symptomatic and asymptomatic cohorts was 100%. Conclusions Sofia has acceptable performance in symptomatic adults when tested < 5 days of symptom onset. Caution should be taken when testing patients with ≥ 5 days of symptoms. The combination of low prevalence and reduced sensitivity results in relatively poor performance of in asymptomatic patients. NAAT-based diagnostic assays should be considered in when antigen testing is unreliable, particularly in symptomatic patients with > 5 days of symptom onset and asymptomatic patients.
【저자키워드】 COVID-19, SARS-CoV-2, PCR, Asymptomatic, antigen test, symptomatic, 【초록키워드】 reliability, point of care, diagnostic, RT-PCR, Symptoms, Laboratory, Antigen, COVID-19 disease, Prevalence, Nasopharyngeal swab, sensitivity, Adults, Cohort, Symptomatic patients, Patient, nasal swab, Cepheid, false-negative, asymptomatic patients, patients, Combination, IFA, symptom onset, caution, offer, Result, collected, develop, was collected, reduced, less, transported, Limited, symptomatic adult, symptomatic and asymptomatic, symptomatic patient, 【제목키워드】 SARS-CoV-2 antigen, performance, single-center, symptomatic and asymptomatic,