VirIntel Covid-19 Test
What is COVID-19 Serological Testing
A serological test is a way to tell if someone’s immune system has learned to create antibodies that fight a particular infection. In some cases of COVID-19 without severe symptoms, the serological test may be the only way to confirm that someone has immunity after the virus itself has already cleared out of their body.
The VirIntel COVID-19 Antibody Test
The VirIntel COVID-19 Antibody Test is a qualitative in vitro diagnostic test for the detection of antibodies to SARS-Cov-2 in human serum samples. The test identifies individuals with an adaptive immune response to SARS-CoV-2, indicating recent or prior infection. Serological surveys are also used in epidemiological studies to determine the prevalence and spread rate of a disease within a population.
VirIntel's COVID-19 Antibody Test allows detection of IgG antibodies to two proteins of SARS-CoV-2 providing comprehensive data on the immune response to the infection:
- A spike protein (S) receptor-binding domain (RBD), considered to be the primary target for neutralizing antibodies against SARS-CoV-2 and
- A nucleocapsid phosphoprotein (N), the one that sits inside the virion, and is presented to immune system not at the onset of the infection, but only after the infected cells start producing new virus and die releasing some of the contents.
The VirIntel COVID-19 Test Difference
- Measuring antibodies against two viral proteins makes the test more robust by eliminating noise and resulting in very high specificity.
- Built-in threshold normalization enables the comparison of antibody levels across populations and labs.
- The VirIntel COVID-19 testing approach has potential to be more sensitive/specific than measuring response to only one antigen. VirIntel is pursuing FDA EUA review and NIH validation.
- The ELISA format makes it compatible with broadly available equipment and works well for both small and large labs.
- Results made available through the person-centric diagnostics reporting and analytical platform to track and report on COVID-19 testing results.
The VirIntel COVID-19 Test Performance Metrics
Clinical Performance
The clinical performance of the VirIntel COVID-19 Antibody Test was assessed with specimens obtained from a general asymptomatic population of pre-epidemic individuals and specimens from donors recovered from COVID-19.
Clinical Specificity
A total of 89 specimens collected prior to the outbreak of the COVID-19 pandemic were tested. Five of these specimens were HIV positive. The test results were considered positive if both RBD and N analysis results appeared above the respective thresholds. The study yielded no false positives results; thus, the specificity of the test was 100% (89/89).
Clinical Sensitivity
A total of 31 specimens (COVID-19 Panels A-1 and A-2, Access Biologicals, LLC) from donors who were determined COVID-19-positive using a SARS-CoV-2 RT-PCR assay (TaqPath COVID-19 Combo kit, ThermoFisher Scientific) 4-8 weeks before the blood draw were used for the clinical sensitivity validation. The test results were considered positive if both RBD and N analysis results appeared above respective thresholds. The study yielded 2 false negative results; thus, the sensitivity of the test was 93.6% (29/31).
