Evaluation of the sensitivity and specificity of ELISA kits for the SARS-CoV-2 diagnosis

Serological method has been used as an auxiliary tool in the clinical severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis due to the low sensitivity of reverse transcription-polymerase chain reaction (RT-PCR) method for respiratory specimens. The serums from 57 confirmed COVID-19 patients, 10 healthy cohorts and 46 tuberculosis patients were employed to determine the sensitivity and specificity of two commercially available enzyme linked immunosorbent (ELISA) kits in their detections of SARS-CoV-2. The sensitivity and specificity of ELISA kit from Beijing company can reach 87.8% and 83.9%, respectively, suggesting a high practical application value. In contrast, the ELISA kit from Zhuhai shows a lower sensitivity (70.1%) but a slightly higher specificity (89.2%). Moreover, a higher detection rate of SARS-CoV-2 IgM is observed in patients that have a longer duration of disease (more than 14 d after onset) than that of people presenting clinical symptoms less than 14 d. Collectively, these results prove the feasibility of SARS-CoV-2 IgM detections by ELISA in the clinical SARS-CoV-2 diagnosis, although these commercially available ELISA kits show different capacities in their diagnosis.