Multicenter evaluation of the Panbio™ COVID-19 Rapid Antigen-Detection Test for the diagnosis of SARS-CoV-2 infection

Abstract

The standard RT-PCR assay for COVID-19 is laborious and time-consuming, limiting the availability of testing. Rapid antigen-detection tests are faster and less expensive; however, the reliability of these tests must be validated before they can be used widely. The objective of this study was to determine the reliability of the PanbioTM COVID-19 Ag Rapid Test Device (PanbioRT) (Abbott) for SARS-CoV-2 in nasopharyngeal swab specimens. This was a prospective multicenter study in ten Spanish university hospitals of patients from hospital units with clinical symptoms or epidemiological criteria for COVID-19. Patients whose onset of symptoms or exposure was more than 7 days earlier were excluded. Two nasopharyngeal exudate samples were taken to perform the PanbioRT and a diagnostic RT-PCR test. Among the 958 patients studied, 359 (37.5%) were positive by RT-PCR and 325 (33.9%) were also positive by the PanbioRT. Agreement was 95.7% (kappa score: 0.90). All 34 false-negative PanbioRT results were in symptomatic patients, with 23.5% of them at 6–7 days since the onset of symptoms and 58.8% presenting CT >30 values for RT-PCR, indicating a low viral load. Overall sensitivity and specificity for the PanbioRT were 90.5% and 98.8%, respectively. The PanbioRT provides good clinical performance as a point-of-care test, with even more reliable results for patients with a shorter clinical course of the disease or a higher viral load. While this study has had a direct impact on the national diagnostic strategy for COVID-19 in Spain, the results must be interpreted based on the local epidemiological context.

Diagnostic performance of a SARS-CoV-2 rapid antigen test in a large, Norwegian cohort

“…In our study, the overall specificity of the antigen test was found to be very high (99.9 %). This is consistent with previous reports, which all showed specificity numbers close to 100 % ( [6] , [7] , [8] , [9] , [10] , [11] , [12] ). False positive results are thus rare.…”

“…In the samples with ct values below 30, we found the RAT’s sensitivity to be 83.8 %. This is in line with previous studies which also found an association between high viral load (ct values < 30 or viral load > 10 6 copies/ml) and increased sensitivity, with reports ranging from 80.0 % to 98.0 % ( [6] , [7] , [8] , [9] , [10] , [11] , [12] ). This indicates that the majority of infectious cases can be correctly identified with the RAT.…”

“…Our data shows that for SARS-COV-2 infected patients with symptom duration less than five days, the sensitivity of the RAT was about 80 %, and when restricting the analysis to individuals with an expected contagious viral load (ct value < 30), the sensitivity was 87.6 %. This is in line with other studies of the Panbio RAT, where sensitivity ranged from 77.2 % to 95.8 % when only patients with symptom duration of less than one week were considered ( [6] , [7] , [8] , [9] , [10] , [11] , [12] ).…”

“…The prevalence in Oslo during the study period was low to medium with a prevalence rate in all samples from Aker test station at 5.7 % (unpublished data), which made it particularly important to conduct an independent evaluation. The overall sensitivity reported by the aforementioned studies varied between 60.5 % and 90.5 % ( [6] , [7] , [8] , [9] , [10] , [11] , [12] ). Studies comprising mainly symptomatic persons described higher sensitivity, all above 80 % ( 6 , 8 , 9 , 12 ), whereas the populations in the two studies reporting the lowest sensitivities (60.5 % and 71.4 %) both contained large fractions of asymptomatic individuals ( 7 , 10 ).…”

“…Recent large prospective studies on the Panbio RAT have included from 913 to 4138 participants and were performed in settings with relatively high SARS-CoV-2 prevalence, ranging from 9.6 % to 40.1 % ( [6] , [7] , [8] , [9] , [10] , [11] , [12] ). The prevalence in Oslo during the study period was low to medium with a prevalence rate in all samples from Aker test station at 5.7 % (unpublished data), which made it particularly important to conduct an independent evaluation.…”