The sensitivity and specificity of COVID‐19 rapid anti‐gene test in comparison to RT‐PCR test as a gold standard test

BACKGROUND: Coronavirus disease 2019 (COVID‐19) is a modern infectious disease, first identified in December 2019 in Wuhan, China. The etiology is via severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), in a pandemic manner. The study aimed to compare between RT‐PCR and rapid anti‐gene tests for COVID‐19 with regard to sensitivity and specificity. METHODS: This is a cohort hospital‐based study done during the period of July to September 2020. Both rapid anti‐gene test kit (SARS‐CoV‐2) and RT‐qPCR were used for the detection of COVID‐19 in suspected cases. RESULTS: A total of 148 cases were tested using both the RT‐qPCR and rapid test. Twenty‐nine (19.6%) of these cases had positive results for RT‐qPCR and 119 (80.4%) were negative, whereas 52 (35.1%) patients were positive to rapid anti‐gene test and 96 (64.9%) of them negative. The sensitivity of the rapid test was 37.9%, the specificity was 65.5% and the accuracy was 64.44%. Rapid IgG test was positive in 47 (31.8) of cases. Although, rapid IgM test was positive in 18 (12.2%). The rapid IgG test was more sensitive than rapid IgM (Sensitivity 34.48% vs. 3.45%), but it was less specific than rapid IgM test (Specificity 68.91% vs. 85.71%). CONCLUSION: We cannot consider rapid anti‐gene test alone as a diagnostic method for COVID‐19. We should also conduct RT‐PCR test and other investigations like imaging CT scan of chest to confirm the diagnosis. The rapid IgG test is more sensitive than rapid IgM, but it was less specific.