Diagnostic accuracy evaluation of a point-of-care antigen test for SARS-CoV-2 and influenza in UK primary care (RAPTOR-C19)
Fanshawe TR., Tonner S., Turner PJ., Głogowska M., Ukwatte U., Okusi C., Cogdale J., Zambon M., Nicholson BD., Richard Hobbs FD., Hayward GN., Arundell K., Kenyon H., Lee JJ., Lucas K., Smylie J.
Objectives To evaluate the diagnostic accuracy of the Roche SARS-CoV-2 & Flu A/B Rapid Antigen Test at the point of care. Design Prospective diagnostic accuracy study. Setting 17 primary care practices in England. Participants 500 individuals with symptoms consistent with possible SARS-CoV-2 or influenza infection identified upon presentation to primary care or via medical note review. Primary and secondary outcome measures Sensitivity, specificity and predictive values, compared to a laboratory reference standard of real-time reverse transcription PCR, using samples collected using a combined nasal and oropharyngeal swab. Of 481 participants with available index and reference test results, 5.6% (27/481) were reference standard-positive for SARS-CoV-2, 11.4% (55/481) for Influenza A and 1.9% (9/481) for Influenza B. The sensitivity of the antigen test to detect SARSCoV-2 was 70.4% (19/27, 95% CI 49.6–86.2%) and specificity was 99.3% (451/454, 95%CI 98.1–99.9%). For Influenza A, sensitivity was 29.1% (16/55, 95% CI 17.6–42.9%) and specificity 98.6% (420/426, 97.0–99.5%), and for Influenza B, sensitivity was 22.2% (2/9, 2.8–60.0%) and specificity 98.1% (463/472, 96.4–99.1%). Conclusions In a primary care population of symptomatic individuals, the assay was highly specific and had moderate sensitivity to detect SARS-CoV-2, but did not detect the majority of influenza infections.