SARS-CoV-2 / UK / SA Variant Triplex Real-Time PCR Detection Kit

GENERAL INFORMATION The SARS-CoV-2/UK/SA Variant Triplex kit is a qualitative detection assay, based on real-time RT-PCR technology, of viral RNA variants of SARS-CoV-2. The kit is used on previously extracted nucleic acid samples. A real-time PCR thermocycler is necessary for the use of the kit. The kit’s results allow to detect the presence of SARS-CoV-2 and to identify whether it is the VOC202012/01 variant (known as « English Variant ») or the 501Y.V2 variant (known as « South African or Brazilian Variant »). PRINCIPLE OF THE TEST The PCR system of the SARS-CoV-2/UK/SA Variant Triplex assay amplifies specifically 2 target sequences of SARS-CoV-2 coronavirus located on the sequence encoding the nucleocapsid (N) protein and the gene encoding RNA-dependent RNA polymerase (called RdRP). These targeted sequences are specific to the SARS-CoV-2 strain. In order to screen and identify the variants, the assay amplifies two target sequences at the level of the spike protein coding sequence (S) which one is specific to both VOC202012/01 and 501Y.V2 variants and the other is specific to the VOC202012/01 variant only. SARSCoV-2/UK/SA Variant Triplex is a triplex qualitative system that allows, for each sample, the simultaneous amplification of target RNAs in one unique reaction. Primers and dual-labeled probes (hydrolysis probe) are built in a specific region allowing sensitive and specific amplification and detection of SARS-CoV-2 virus’ RNA and of variants if they are present in the sample. The SARS-CoV-2/UK/SA Variant Triplex assay is a PCR of second intention that allows to screen SARSCoV-2 positive samples. Therefore, an initial PCR used to determine SARS-Cov-2’s presence must be done prior to the ID SARS-CoV-2/UK/SA Variant Triplex assay. Nucleic acid presence is detected through a fluorescence increase due to the probe’s hydrolysis during amplification. Fluorescence signals for N and RdRP genes’ specific probes’ amplification are measured in the Cy5 channel (N and RdRP targets) ; the signal for the VOC202012/01 variant’s detection is measured both in the FAM channel (Spike Del69-70) and the VIC/HEX channel (Spike N501Y), whereas the 501Y.V2 variants are measured in the VIC/HEX channel only (N501Y target). MATERIALS AND REAGENTS RESULTS INTERPRETATION Presence or absence of SARS-CoV-2 RNA in the tested sample is qualitatively determined thanks to obtained Cq values (Quantification cycle) for each sample and for each target. For each analyzed sample, the results must be interpreted according to the following criteria: A signal is considered as positive if there is detection of a Cq and a characteristic curve. Cq’s absence corresponds to a negative sample or to an inhibited sample. A Cq equal or higher to 36 cycles for the Cy5 SARS-CoV-2 target corresponds to a sample “under the detection limit” and must not be considered. PERFORMANCE CHARACTERISTICS 1. Analytical sensitivity - LImit of Detection The screening test sensitivity is 10 copies/PCR for Del69-70 and N501Y targets. 2. Clinical performance evaluation Relative sensibility of the assay: 100% (44/44) Relative specificity of the assay: 100% (44/44) CE-IVD marked