Study of the Immune Response of COVID-19 Patients in Kirkuk Province

Abstract

Abstract Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a novel coronavirus causing coronavirus disease 2019 (COVID-19); it is diagnosed based on clinical signs and laboratory detection methods such as polymerase chain reaction (PCR) and serological techniques. Objective: The objective of the study is to use other diagnostic methods that support the PCR method of diagnosis for COVID-19. Materials and Methods: The study included 90 COVID-19 patients and 26 control group. Nasopharyngeal swabs were collected from the suspected patients with COVID-19 infection for the detection of the RNA virus by PCR technique. If the PCR was positive, the serum samples were collected and used for the quantitative detection of SARS-CoV-2 S1 (IgM, IgG) by using enzyme linked immunosorbent assay. Results: The result of this study showed that in a total of 116 participants, there was a significant difference between IgM and IgG reactivity (±) and the number of PCR-positive and negative individuals with P value <0.0001 and P value = 0.003, respectively. In addition, a significant increase in the levels of IgM and IgG (P ≤ 0.0001 for IgM and P ≤ 0.0001 for IgG) was recorded in patients compared with healthy control. Moreover, a significant correlation between IgM level with P = 0.0018 and the onset of symptoms as well as positive correlation was noticed between IgG concentration and the onset of symptoms (P = 0.0272). Conclusion: The study concluded that antibodies developed against COVID-19 infection could appear at early stages of the infection without the confirmation of real time polymerase chain reaction, and this could be a beneficial tool for early screening of suspected as well as asymptomatic individuals.