ABSTRACT
Abstract Background The performance characteristics of the Panbio™ COVID-19 Ag test was evaluated at an emergency room setting against RT-PCR, considered the gold-standard for the detection of SARS-CoV-2, in São Paulo, Brazil. The study aimed to determine the sensitivity, specificity, Positive Percent Agreement (PPA), and Negative Percent Agreement (NPA) as compared to RT-PCR. Methods Specimens from 127 suspected patients were tested by both the Panbio™ COVID-19 Ag test and by RT-PCR. Results In relation to RT-PCR using Ct values ≤ 40 as the upper limit for positivity, the Panbio™ COVID-19 Ag test showed an overall sensitivity of 84.3% (95% CI 75‒93.8%) and 98.2% (95% CI 96‒98.8%) overall specificity. For Ct values ≤ 25 (n= 37), the Panbio™ COVID-19 Ag test showed 97% sensitivity. Discussion The concordance between the Panbio™ COVID-19 Ag test and RT-PCR was 97% at Ct values below 25 but decreased at higher Ct values. For disease control, it is very important to identify infected individuals who present COVID-19 symptoms and also those who are suspected of infection due to contact with infected individuals. Conclusion The Panbio™ COVID-19 Ag test is suitable for use as a diagnostic test for rapid screening of patients presenting COVID-19 symptoms, or those suspected of being infected, prior to being admitted to hospital.