Performance & Quality Evaluation of Marketed COVID-19 RNA Detection Kits

Compared to other coronaviruses, COVID-19 has a longer incubation period and features asymptomatic infection at a high rate (>25%)1,2. Therefore, early detection of infection is the key to early isolation and treatment. Direct detection of the virus itself has advantages over indirect detection. Currently, the most sensitive and commercially validated method for COVID-19 testing is RT-qPCR, designed to detect amplified virus-specific RNA. Reliable testing has proven to be a bottleneck in early diagnosis of virus infection in all countries dealing with the pandemic. Significant performance and quality issues with available testing kits have caused confusion and serious health risks. In order to provide better understanding of the Quality and performance of COVID-19 RNA detection kits on the market, we designed a system to evaluate the specificity (quantitation), sensitivity (LOD) and robustness of the kits using positive RNA and pseudovirus controls based on COVID-19 genomic sequence3,4. We evaluated 8 Nucleic Acid qPCR Kits approved in China, some of which are also approved in the US and EU. Our study showed that half of these 8 kits lack 1:1 linear relationship for virus RNA copy: qPCR signal. Of the 4 with linear response, 2 demonstrated sensitivity at 1 Copy viral RNA/Reaction, suitable for early detection of virus infection. Furthermore, we established the best RNA extraction, handling and qPCR procedures allowing highly sensitive and consistent performance using BGI qPCR kits. Our study provides an effective method to assess and compare performance quality of all COVID-19 nucleic acid testing kits, globally. Significance StatementTesting for COVID-19 has been a critical topic in the pandemic management since the first outbreak reported in China, and now globally. Despite of focused efforts from global biomedical industries and regulatory authorities, testing tools currently available on the market are not satisfying the huge and most important needs for virus control, which is specific, sensitive, affordable, and commercially viable early diagnosis of infected populations. We have designed an experimental system to assess and compare all nucleic acid-based COVID-19 testing kits from quality control perspectives. The results reported here demonstrate the suitability of using our system as an objective QC system for all commercial kits, including any future kits. We also identified the best testing method using commercially available reagents.