Isothermal Amplification Technology for Diagnosis of COVID-19: Current Status and Future Prospects

During the COVID-19 pandemic, polymerase chain reaction (PCR) has become the gold standard for the detection of SARS-CoV-2 RNA worldwide. However, PCR-based nucleic acid detection technology remains relatively time-consuming, and requires specialized instrumentation and technical personnel; therefore, PCR is difficult to apply at primary-level medical institutions. Antibody-based detection has limitations because of the late appearance of antibodies, thus making early diagnosis difficult, whereas antigen-based detection has insufficient sensitivity, thus resulting in a high false-negative rate. Here, we briefly summarize the development and applications of the nucleic acid isothermal amplification technique (IAT) and describe four major IATs used for the detection of SARS-CoV-2 RNA in mainland China, which have been officially approved by the National Medical Products Administration. In particular, we elaborate on the strengths and weakness of the different IAT in practical settings. We also discuss the outlook for IAT development and propose considerations for the future use of IATs in China.