Quantitative real time polymerase chain reaction (qRT-PCR)
The qRT-PCR detection of viral nucleic acid test (NAT) was one of the most quickly established laboratory diagnosis method in COVID-19 pandemic. After the throat swab specimens in each patient were collected, the presence of SARS-CoV-2 in throat swab specimens was detected by qRT-PCR amplification of SARS-CoV-2 open reading frame 1ab (ORF1ab) and nucleocapsid protein (NP) genes fragments using QIAampRNA kits. C t value ≦37 was considered positive.