2.1 Patients and controls
The current study was approved by the Institutional Ethics Committee of
the Iraqi Ministry of Health. All participants were informed of the
study objectives and agreed to participate in it through written
consent. In this case-control study, 90 patients diagnosed with
mild/moderate COVID-19 with a median age of 40 years and an
interquartile range (IQR: 25-75%) of 33-46 years (60% males and 40%
females) were enrolled. A control group (HC) of 90 blood donors matched
patients for age (39 [IQR: 34-43] years) and gender (64.4% males
and 35.6% females) was also enrolled in the study. The HC group
included apparently healthy individuals, and serum tests for the blood
bank antibody panel, including SARS-CoV-2 IgM and IgG antibodies, were
negative. The study was conducted on patients admitted to healthcare
units in Anbar Governorate due to signs and symptoms of COVID-19.
Molecular examination of nasopharyngeal swabs confirmed infection with
SARS-CoV-2 (RealLine SARS-CoV-2 kit, Bioron Diagnostics GmbH). In
addition, sera of patients were tested for SARS-CoV-2 IgM and IgG
antibodies (VIDAS SARS-CoV-2 IgM and IgG assay kits; bioMerieux,
France). Inclusion criteria were positive molecular test, positive serum
IgM antibody test, age ≥ 18 years, and mild/moderate disease as defined
in WHO interim guidelines (WHO, 2020). Exclusion criteria were pregnancy
and severe and/or critical COVID-19.