Performance evaluation of the Simtomax® CoronaCheck rapid diagnostic test

Ducrest, P.J.; Freymond, A.; Segura, J.-M.

The aim of this study was to evaluate the diagnostic performance of Simtomax® CoronaCheck, a serology rapid diagnostic test (RDT) for the detection of IgG and IgM against SARS-CoV-2. 48 plasma samples positive for SARS-CoV-2 based on RT-PCR and 98 negative control samples were studied. Diagnostic performance of the IgG/IgM RDT was assessed against RT-PCR and the electro-chemiluminescence immunoassay (ECLIA) Elecsys® Anti-SARS-CoV-2 total Ig. Overall, the RDT sensitivity was 92 % (95 % confidence interval [95 %CI]: 79−97), specificity 97 % (95 % CI: 91−99 %), PPV 94 % (95 % CI: 81−98) and the NPV 96 % (95 % CI: 89−99). When considering only samples collected ≥ 15 days post-symptoms (DPS), the sensitivity increased to 98 % (95 %CI: 86‐100) and the specificity was 97 % (95 % CI: 91−99 %). Two samples with 180 DPS were still positive for IgG. Globally, this IgG/IgM RDT displayed a high diagnostic accuracy for SARS‐CoV‐2 IgG/IgM detection in plasma samples in high COVID‐19 prevalence settings. It could be effectively used, in absence of facilities for routine diagnostic serology, for samples with a DPS between 15 and 180 days.