COVID-19 testing has expanded in recent weeks, to the point where we have the potential to get test results within the same day. One of the problems facing both patients and healthcare workers is that the symptoms for COVID-19 are similar to many other respiratory illnesses. However, there is new testing available that will help LifeBrite Laboratories determine if the patient is experiencing COVID-19 or another illness.
Genotyping technology allows for innovative SARS-CoV-2 testing options
The new assay is composed of several steps. The first stage utilizes extraction kits developed by ThermoFisher Scientific which remove the genomic material from the viral coat, allowing it to be detected in downstream steps. The next step uses real-time reverse transcriptase PCR (real time RT-PCR) to amplify the extracted genomic material. This stage uses primers and probes to look at two targets in the SARS-CoV-2 genome and one target in the human genome. The human gene target acts as a control to ensure the sample was collected properly. By analyzing the results of the real-time RT-PCR, technicians are able to determine if the sample contains SARS-CoV-2 RNA.
Real-time RT-PCR is specific for SARS-CoV-2
Real time RT-PCR sets a threshold that is used to determine if a sample contains SARS-CoV-2 RNA. Samples that exceed the threshold for both SARS-CoV-2 targets are positive. The primers and probes used to detect SARS-CoV-2 will not detect genomic material from other viral infections, including the closely related coronaviruses which cause SARS and MERS or common coronavirus0strains such as 229E, NL63, OC43, and HKU1. Having the ability to rule out other conditions in one test is essential because the symptoms across many different respiratory illnesses can be so similar.
Only samples with SARS-CoV-2 RNA (*) cross the threshold for detection, demonstrating the assay specificity.
A closer look at a COVID-19 test samples
This image shows the results of a real-time RT-PCR run on samples spiked with SARS-CoV-2, human (RPP30 gene), SARS, or MERS genomic material. The table on the left shows lists sample names. The hot pink boxes and stars are for samples that were spiked with known concentrations of non-infectious SARS-CoV-2 RNA.
In the amplification plot on the right, red lines illustrate samples, and the thick black line in the middle is the threshold. This amplification plot shows the results of an assay called N1, which targets part of the nucleocapsid gene of SARS-CoV-2. As shown, each “CoV-2” dilution crosses the threshold at a different point; the 1:100 dilution has more genomic material than the 1:2000 dilution, so it passes the line earlier on the x-axis (~cycle 28 for 1:100 vs cycle 36 for 1:2000). The SARS and MERS samples do not cross the threshold and show that the assay is specific for SARS-CoV-2 and doesn’t incorrectly detect similar viruses.
Increased SARS-CoV-2 testing capacity with the new assay
This newly acquired assay can also help take patient testing to the next level. A significant downfall in recent weeks has been the testing load, or how many tests a laboratory can do in any given day. The new assay that LifeBrite Laboratory developed can test 90 samples at a time, multiple times a day. This testing capacity will help expand the testing reach to many more people and help determine which people are infected.
COVID-19 could be seasonal and quick testing will be essential
This increased testing capacity will be a considerable benefit come October. Scientists already know about the coronavirus season, which starts picking up in October and slows down in April or May as summer descends. It is feasible that SARS-CoV-2 could reappear during this time, too. Especially since coronavirus season coincides with flu and respiratory syncytial virus (RSV) seasons, the ability to determine which illness a patient is suffering from is essential to the physicians’ ability to diagnose and treat effectively.
The ability to determine if a patient is positive for SARS-CoV-2 or other common respiratory illnesses is vital. Not only will it help in treating people, it can help guide others to self-quarantine and slow down the spread when they know they are infected. This new assay makes it easy to determine if a patient is suffering from COVID-19 or another respiratory pathogen, and allows the illness to be identified quickly and on a large scale.
For inquiries about our Respiratory Pathogen Profile testing, please call the corporate office at 678-433-0607
Learn more about LifeBrite Atlanta-based LifeBrite, led by CEO Christian Fletcher. LifeBrite Hospital Group operates LifeBrite Community Hospital of Early, LifeBrite Community Hospital of Stokes, and Lifebrite Laboratories. To learn more about what LifeBrite Hospital Group is doing to make healthcare better, visit our homepage.