Detection of COVID-19 Coronavirus
QuantiVirus™ SARS-CoV-2 Test Kit from DiaCarta (FDA Emergency Use Authorization Granted)
The QuantiVirus™ SARS-CoV-2 Test Kit is based on Real-Time PCR technology, developed for specific detection of SARS-CoV-2 (COVID-19) viral RNA extracted from nasopharyngeal swabs, oropharyngeal swabs and sputum. The sensitivity is 100 copies per mL of SARS-CoV-2 viral with a 95% confidence. The assay is highly specific without cross-reaction with different types of non-SARS-CoV-2 species tested. The clinical validation shows 96.7% sensitivity and 100% specificity.
For Emergency Use Authorization (EUA) only. For prescription use only. For in vitro diagnostic use.
Key Product Information
- FDA Emergency Use Authorization (EUA) Approved
- CE-marked
- Detects three genes, Orf1ab, N and E genes
- Detects different SARS-CoV-2 virus strains
- Sensitivity is 100 copies per mL
- Less than 2 hours from RNA to results on most qPCR machines
Sample Type
Nasopharyngeal Swabs, Oropharyngeal Swabs and Sputum
Instruments Validated
Thermo Fisher (ABI) QuantStudio 5, Thermo Fisher (ABI) 7500 Fast Dx, and Bio-Rad CFX 384
Detection Chemistry
TaqMan
Turnaround Time
~2 hours
Stability
Stable for 12 months at -25°C to -15°C
Performance Characteristics of the QuantiVirus™ SARS-CoV-2 Test Kit
HIGH SENSITIVITY
100 copies per mL of SARS-CoV-2 viral with a 95% confidence
LOW SAMPLE VOLUME
only 2µL viral RNA sample
HIGH ACCURACY
Detection of three target genes for calling positive results
WIDE DYNAMIC RANGE
Allowing detection of from 10 million copies to single copy analyte in linear range
Other COVID-19 Related Products
Fastep® COVID-19 Antigen Home Test (FDA EUA Granted)
Clarity COVID-19 Antigen Rapid Test Cassette (FDA EUA Granted)
Sienna™ COVID-19 Antigen Rapid Test Cassette (FDA EUA Granted)
POC/Waived/Fingerstick Fastep® COVID-19 IgG/IgM Rapid Test Device by Assure Tech. (FDA EUA Granted)
Status™ COVID-19/Flu A&B Antigen Test (FDA EUA Granted)
Diazyme SARS-CoV-2 IgG and IgM Automated Antibody Test Kits for DZ-Lite 3000 Plus (FDA EUA Granted)
QuantiVirus™ SARS-CoV-2 Test Kit from DiaCarta (FDA EUA Granted)
QuantiVirus™ SARS-CoV-2 Multiplex Test Kit from DiaCarta (FDA EUA Granted)
How Does the QuantiVirus™ SARS-CoV-2 Test Kit Work?
Figure 1. Amplicon Target on SARS-CoC-2 genome. E: envelope protein gene; M: membrane protein gene; N: nucleocapsid protein gene; ORF: open reading frame; RdRp: RNA-dependent RNA polymerase gene; S: spike protein gene.
The QuantiVirus™ SARS-CoV-2 Test Kit is a qRT-PCR assay for the qualitative detection of SARS-CoV-2 viral RNA.
Three genes of the SARS-CoV-2 including N, Orf1ab and E are targeted in the qRT-PCR assay and primers and Taqman probes are designed in the conserved region of the SARS- CoV-2 virus-specific genome region to allow sensitive and specific amplification and detection of the virus. The human RNase P gene is used as internal and extraction control to monitor viral RNA extraction efficacy and assess amplifiable RNA/DNA in the samples to be tested.
Assay Performance
The assay has a wide dynamic range as shown in the figure below: Amplification curve of 10 -fold serial dilution of templates showing the dynamic range.
The assay performance summary for QuantiVirus™ SARS- CoV-2 Test Kit
- Intra-assay reproducibility: Coefficient of Variation (%): < 3%
- Operator reproducibility: Coefficient of Variation (%): < 1.5%
- Inter-instrument reproducibility: Coefficient of Variation (%): < 5%
- Assay detection limit (LOD): 1 copy of virus RNA or 100 copies per ml sample
Clinical Evaluation (In Vitro Transcribed Viral RNA Spiking into Sputum)
Clinical evaluation of the QuantiVirus™ SARS-CoV-2 Test kit was conducted with contrived sputum specimens including 30 positive and 30 negative samples. 20 sputum samples were contrived with RNA (in vitro transcripts) templates at 2xLOD (2×100 copies/mL) and 10 sputum samples were contrived with different higher RNA (500, 1000, 5000 and 10000 copies/uL). 30 specimen were contrived only with water as the negative control. The contrived clinical samples were tested blindly to generate the Positive Predictive Value (PPV), Negative Predictive Value (NPV) as a measurement of estimated Diagnostic Accuracy.
Data show that there is a 95% agreement with the spiking sample with 2X LOD (2×100 copies/mL), but one sample cannot be detectable. With higher concentration spiking samples (500, 1000, 5000 and 10000 copy/uL), 10 out of 10 samples were detectable. For negative control, Thirty samples were negative.
Table: Contrived clinical sample evaluation with in vitro transcribed RNA
The above table shows:
- Clinical Sensitivity = 96.7% (95% CI, 81.4%-99.8%)
- Clinical Specificity = 100% (95% CI, 85.4%-100%)
- Positive Predictive Value (PPV) = 100% (95% CI, 85.8%-100%
- Negative Predictive Value (NPV) = 96.6% (95% CI, 80.9%-99.8%)
Third-Party Clinical Test Results
The third-party clinical test results demonstrated that DiaCarta’s QuantiVirus™ SARS-CoV-2 Test Kit shared the same testing results (100% match), compared with peer products, even at much lower sample concentration in some cases.
| Sample ID | Abbott m2000 | CDC Assay | DiaCarta's QuantiVirus™ Assay |
|---|---|---|---|
| A | Detected | Detected at 1:100 dilutions | |
| B | Detected | Detected at 1:1000 dilutions | |
| C | Not Detected | Not Detected | Not Detected |
| D | Not Detected | Not Detected | Not Detected |
| E | Not Detected | Not Detected | Not Detected |
| F | Not Detected | Not Detected | Not Detected |
| G | Not Detected | Not Detected | Not Detected |
| H | Not Detected | Not Detected | Not Detected |
| I | Not Detected | Not Detected | Not Detected |
| J | Detected | Detected | Detected |
| K | Detected | Detected | |
| L | Detected | Detected | |
| M | Detected | Detected | Detected |
| N | Not Detected | Not Detected | Not Detected |
Important Information
The QuantiVirus™ SARS-CoV-2 Test Kit and Quanti-Virus™ SARS-CoV-2 Multiplex Test Kit from DiaCarta have not been FDA cleared or approved; these tests have been authorized by FDA under an EUA for use by authorized laboratories certified under the Clinical Laboratory Improvement Amendments (CLIA) of 1988, 42 U.S.C. §263a, to perform high complexity tests. These tests have been authorized only for the detection of nucleic acid from SARS-CoV-2, not for any other viruses or pathogens. These tests are only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostic tests for detection and/or diagnosis of COVID-19 under Section 564(b)(1) of the Act, 21 U.S.C. § 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner. Instructions for Use and Fact sheets for Healthcare Providers and Patients can be found at carolinachemistries.com.
Streamlined Workflow for the QuantiVirus™ SARS-CoV-2 Test Kit
Step 1: Extract RNA from patient sample and extraction control using Thermo Fisher PureLink viral RNA/DNA mini kit or Qiagen QIAamp® Viral RNA Mini Kit
Step 2: Set up the assay reactions using primer/probe mixes, and one-step RT-qPCR master mix. A positive (PC), NTC (NC)and extraction control (EC) must be included for every run
Step 3: Perform RT-qPCR using the Applied Biosystems™ QuantStudio 5, or 7500 Dx or BioRad CXF 384 Real-Time PCR Instrument
Step 4: Data analysis and review results interpretation for patient samples
Coronavirus (SARS-CoV-2) Detection Tests are Crucial
The global outbreak of novel coronavirus, SARS-CoV-2 (COVID-19), caused over 3000 people’s death and huge economic damage. The number is still increasing. Detecting the virus early is essential to contain the virus from infecting more people. However, in the United States, the unavailability of enough reliable detection kits in time has caused concerns and panic in the society.
*The numbers are calculated on March 9, 2020 by https://www.worldometers.info/coronavirus/
- Without the test, the general public does not know if they get the novel coronavirus or the regular flu virus as they share similar symptoms
- Without the test, the general public does not know if they carry the virus without symptoms and further infect their closed ones and others who have contact with them
- Without the test, the general public does not know if they carry the virus and miss the treatment window
To meet the unmet medical needs, DiaCarta has developed the QuantiVirus™ SARS-CoV-2 Test Kit to accurately detect the virus with high sensitivity using nasopharyngeal swabs, oropharyngeal swabs and sputum.
