Panbio antigen rapid test is reliable to diagnose SARS CoV 2 infection in the first 7 days after the onset of symptoms
Background RT qPCR is the current recommended laboratory method to diagnose SARS CoV 2 acute infection, several factors such as requirement of special equipment, time consuming, high cost and skilled staff limit the use of these techniques. A more rapid and high throughput method is essential. Methods We analyzed clinical data and nasopharyngeal samples, collected during September 2020, from patients attended at the emergency department of a secondary hospital and in two primary healthcare centers in Madrid. The performance of the Panbio(tm) COVID 19 AG Rapid Test Device for the detection of SARS CoV 2 antigen was compared to RT qPCR. Results 255 nasopharyngeal swabs, including 150 from the emergency department and 105 from primary helthcare centers, were tested. 184 patients were symptomatic (72.1 Amongst the 60 positive RT qPCR samples, 40 were detected by the rapid antigen test, given an overall sensitivity of 73.3 All the samples detected positive with the rapid antigen test were also positive with RT qPCR. The median cycle threshold was 23.28 (IQR 18.5 30.16) Patients with less than seven days onset of symptoms showed a higher viral load, and sensitivity for rapid antigen test (86.5 compared to those with more days (sensitivity of 53.8 (p 0.004) Conclusions The rapid antigen test evaluated in this study showed a high sensitivity and specificity in samples obtained during the first week of symptoms and with high viral loads. This assay seems to be an effective strategy for controlling the COVID 19 pandemic for the rapid identification and isolation of SARS CoV 2 infected patients.
Journal of Clinical Virology