Evaluation of the COVID-19 IgG/IgM Rapid Test from Orient Gene Biotech

Abstract

While the coronavirus disease 2019 (COVID-19) pandemic has peaked in many countries already, the current challenge is to assess population immunity on a large scale. Many serological tests are available and require urgent independent validation. Here, we report performance characteristics of Orient Gene Biotech COVID-19 IgG/IgM Rapid Test Cassette (OG) and compare it to Abbott SARS-CoV-2 IgG immunoassay (ASIA). Patients (n = 102) with a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcriptase PCR (RT-PCR) were tested. The patients were asymptomatic (n = 2) or had mild (n = 37) or severe symptoms requiring hospitalization in a medical unit (n = 35) or intensive care unit (n = 28). Specificity was evaluated for 42 patients with previous viral and parasitic diseases as well as a high level of rheumatic factor. The sensitivity of OG was 95.8% (95% confidence interval [CI95%], 89.6 to 98.8) for samples collected ≥10 days after the onset of symptoms, which was equivalent to the sensitivity of ASIA of 90.5% (CI95%, 82.8 to 95.6). OG uncovered six false-negative results of ASIA, of which two had only IgM with OG. Specificity was 100% (CI95%, 93.4 to 100) with both tests on samples, including patients infected with endemic coronavirus. Overall, OG performance characteristics indicate that the test is suitable for routine use in clinical laboratories, and its performance is equivalent to that of immunoassay. Testing OG on a larger asymptomatic population may be needed to confirm these results.

Keywords: COVID-19; lateral flow assay; rapid test.

FIG 1

Percentage of Orient Gene tests displaying IgM alone, IgG alone, or both IgM and IgG according to the number of days from the onset of symptoms.

FIG 2

Global overview of results of 106 serum samples from patients with a positive SARS-COV-2 RT-PCR tested for IgG with Abbott SARS-CoV-2 IgG assay and tested for IgG and IgM with Orient Gene Rapid Test Cassette (OG). Data are shown according to the number of days from the onset of symptoms. Positive tests are represented by gray row, negative tests by white rows. Discrepancies between IgG results by OG and ASIA are indicated by a single asterisk. Serum samples positive for IgM only by OG are indicated by two asterisks. Colored boxes represent samples from the same patients (n = 4).