Laboratory Diagnostic Testing for COVID-19

Laboratory tests play an important role for Corona Virus Disease 2019 (COVID-19) diagnosis. The diagnostic key point is an appropriate testing during the course of disease. In the early course of COVID-19 infection, nucleic acid amplification tests (NAATs) especially real-time reverse-transcription polymerase chain reaction (RT-PCR) of the respiratory specimen is the gold standard test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection due to the highest sensitivity and specificity during the first 2 weeks after the exposure. A rapid antigen test for SARS-CoV-2 has less complexity of the testing procedure and the faster TAT. However, a rapid antigen test has less sensitivity compared to NAATs. Serological tests for COVID-19 are recommended for assisting the diagnosis in some indications and focused on epidemiological study. Viral isolation and genomic sequencing are not routinely used for COVID-19 diagnoses, but they are important for the study of viral mutation and outbreak investigation.