Bacteriological and immunological study of SARS-CoV-2 patients in Iraq using some genetic and immune signals

The aim of this study was to evaluate the secondary bacteria causing lung infection in COVID-19 patients and to determine the most appropriate method for molecular immunoassays by detecting the sensitivity and specificity of the reactions by detecting gene expression and its relationship with the immune indicators studied, as well as immune factors associated with secondary bacterial infection in SARS patients. To this end, 236 Iraqi patients infected with COVID-19 participated in this study. All patients were confirmed to be infected with SARS-COV-2 using polymerase chain reaction from nasopharyngeal swab. Blood samples and nasopharyngeal swab samples were collected from participants for further analysis under the guidance of a medical professional. The study groups were divided into SARS patients with mild infection, a group of patients with primary lung damage due to severe and moderate viral infection, and healthy individuals. From previously vaccinated infected patients of different ages, demographic data, symptoms, history of comorbidities, dietary habits, medication history, biochemical reports and clinical history of SARS-CoV-2, patient age, gender, duration of infection and type of chronic disease, if any, were obtained. In addition, the types of vaccines received by previously infected and unvaccinated patients were also considered as a separate group in order to compare the variables examined according to these types. Pregnant and breastfeeding women, as well as patients who expressed unwillingness to participate, were excluded. The ages of the study participants ranged from 17 to 89 years. Samples were examined for secondary bacterial pneumonia confirming the presence of infection. Risk factors associated with this infection were also identified and some immunologic and genetic markers were evaluated. Sputum samples, nasopharyngeal swabs and oral swabs were used to isolate and identify different bacterial species. A higher prevalence of secondary bacterial pneumonia was observed in males (67%) compared to females (35.6%). The Kirby-Bauer method was used to assess antimicrobial drug susceptibility and 11 antibiotics were injected into Mueller-Hinton agar. Enzyme linked immunosorbent assay (ELISA) technique was used to check TLR-2, ACE-2, FASL, RBD, IgG and IgM levels as well as some genetic and immunological markers. These markers showed significant associations with each other and with bacteria study showed diversity among infection-associated bacterial species, pathogenic bacteria and the microbiome. Bacterial resistance and virulence rates were also modified through biofilm testing using quantitative and qualitative methods. At the molecular level, viral load and cycle thresholds of SARS-CoV-2 genes were altered. Several genes were studied. The expression levels of the main bank gene in the infected study samples, as well as the relationship between these molecular markers and immunological measurements in the study groups were examined, provided there were no other significant associations.