Methods: A total of 194 frozen nasopharyngeal swab samples (from 2016-2018) obtained from children aged ≤18 years and previously tested by RP as a routine clinical testing were included in this study. These samples were tested by all three fusion assays. Positive percent agreement (PPA) and negative percent agreement (NPA) of Fusion assays were calculated against RP assay.
Results: Among 194 samples, 58.0% were from male. Median age was 36 months (IQR 13-72 months). Overall agreement between two assays was 82.5% (95% CI 77.6-88.1). PPA and NPA of Fusion assays for each target was; Flu A- 100.0% and 100.0%, Flu B-95.0% and 100.0%, RSV-90.1% and 94.0%, adenovirus- 80.0% and 98.2%, hMPV- 95.2% and 99.4%, Rhino-79.1% and 95.8%, Parainfluenza virus-100.0% and 100.0% respectively. There were total 34 discrepant samples. Among these, majority were rhino (n=12), RSV (n-12) and adenovirus (n=7). Of 12 rhinovirus discrepant samples, Fusion assay detected additional 7 but missed 5 samples. For 12 RSV discrepant samples, fusion assay detected 10 more RSV but missed 2. Fusion assay missed 4 adenovirus and detected additional 3 samples. All discrepant samples, especially rhinovirus positive samples need further investigation since RP detects both rhinovirus and enterovirus whereas the Fusion assay detects rhinovirus only.
Conclusion: Performance of Fusion Flu A/B/RSV and Paraflu assays were comparable with RP assays. Fusion AdV/hMPV/RV assay had the highest discrepancy with RP assay. Overall, Panther Fusion respiratory assays provide the opportunity to customize testing with smaller respiratory panels at a reduced cost.
D. Banerjee, None
R. Selvarangan, None