Assessment of IgM/IgG Antibody Detection in Comparison with RT-PCR Technique for Diagnostic Purposes in Patients with COVID-19

The diagnosis of COVID-19 is an essential step toward controlling the pandemic. For this purpose, a series of laboratory methods have been developed. This study evaluated the efficiency of the ELISA method for COVID-19 IgM and IgG detection.

In this case-control study, 46 blood samples from PCR positive COVID-19 patients and 49 samples from PCR negative COVID-19 subjects were collected. Subsequently, the presence of IgM and IgG in all blood samples was assessed using the Pishtaz Teb ELISA kit.

 The data demonstrated that among 49 PCR negative, 40 (81.6%) were IgM negative and 9 (19.1%) were IgM positive. Besides, out of the 49 PCR-negative patients, 42 (85.7%) and 7 (14.3%) were IgG negative and positive, respectively. In 46 PCR-positive individuals, 40 (87%) were IgM negative, while 6 (13 %) were IgM positive. Of the 46 PCR-positive patients, 24 (52.2%) were IgG negative, and 22(47.8%) were IgG positive.

 Our results showed that detection of SARS-CoV-2 IgG and IgM using Pishtaz Teb ELISA kit is not enough for COVID diagnosis, but it can serve as a diagnostic RNA supplement to confirm infection with SARS-CoV-2 in approved clinics and other scientific communities, owing to its easy, rapid, and inexpensive availability.