The Testing Imperative*
Rapid diagnostics of people infected with SARS–CoV-2, the virus causing COVID-19, is central to control the global pandemic that erupted in late 2019. Several countries have used massive-scale testing as a cornerstone of their successful containment strategies. In contrast, the United States, hampered by limited testing capacity, has prioritized testing for specific groups of persons and has struggled to break transmission chains and effectively contain the virus on several instances.
Multiplexed Detection of SARS-CoV-2 Structural Proteins
Current Testing Methods and Gaps
Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) tests performed in a laboratory on respiratory specimens are the reference standard for COVID-19 diagnostics, showing high sensitivity and specificity. However, the method is complex to use, slow to deliver results, susceptible to sample collection errors, and not suitable for use in a low-resource environment. Other attempts have emerged at offering point-of-care technologies and serologic immunoassays yet these lack the sensitivity and specificity required to provide a decisive solution.
Although tools exist for the diagnosis of symptomatic patients in well-equipped laboratories, important gaps remain in screening asymptomatic persons in the incubation phase, as well as in the accurate determination of live viral shedding during convalescence to inform decisions to end isolation. Many affluent countries have encountered challenges in test delivery and specimen collection that have inhibited rapid increases in their testing capacity. These challenges may be even greater in low-resource settings.
Q-SENS Brings Multiplexed, Sensitive Antigen Testing to the Point-of-Care
Our technology has the ability to combine the performance of central-lab analyzers with a highly multiplexed panel at the Point of Care, thus making antigen testing an excellent solution for monitoring outbreaks such as COVID-19.
Evidence shows the ability to detect Coronavirus antigen (e.g. Nucleocapsid protein) of SARS-CoV-2 in multiple body fluids within a couple of days of onset of symptoms. While it may not be suitable for the initial diagnosis, it can be extremely useful during the ‘Symptomatic Illness’ and ‘Convalescence’ periods.
Multiplexing can significantly improve specificity by including all four SARS-CoV-2 structural proteins (S, N, M & E) as well as antigen tests for other strains of Coronavirus, thus eliminating ‘false positives'. In addition, multiple positive and negative controls can eliminate erroneous results.
Quantitative vs. Qualitative Results
Quantification of the viral proteins, when running multiple/daily tests, can provide clinicians with crucially useful information on the progression of the disease, which will be important even after a vaccine is found and therapeutics are developed. It can also assist in making the decision to end patient isolation, once the viral proteins drop below the level of detection and remain there for a predefined period of time.
At the Point of Use / Home
Having a connected system at the Point-of-Use (transportation hubs, schools, workplaces, or even ones' home), combined with ease of use that allows for self-administration of the test, gives physicians the option of keeping some patients quarantined in their homes, thus minimizing the risk for healthcare workers and other hospitalized patients.