Serological Studies of IgG and IgM in Response to SARS-CoV-2 Vaccination in Erbil, Kurdistan-Iraq.

The ongoing global pandemic of coronavirus disease (Covid-19) has had a considerable impact on healthcare systems and economies worldwide. The aim of vaccines against the virus is to elicit an immune response against the spike protein of the SARS-CoV-2 virus, with the objective of neutralizing the virus. Efficacy has now been demonstrated for several vaccinations, including those based on mRNA, adenoviral-vectored protein subunits, and whole-cell inactivated subunits. A comprehensive understanding of the immune responses to these vaccines, and the manner in which different antibodies are generated following vaccination, is imperative to enhance our comprehension of the pathophysiology of the disease. The present study aims to provide a comparative analysis of the humoral immune responses elicited by BNT162b2 (mRNA-based), BBIBP-CorV (inactivated virus), and ChAdOx1 (dsDNA-recombinant) vaccines against the SARS-CoV-2 virus. The study population comprised 321 individuals, with 90 individuals who had not received any vaccines (control group) and 77 individuals who had received the Pfizer and Sinopharm vaccines, respectively. Blood samples were collected 10 weeks after vaccination, and serum analysis was performed. The human SARS-CoV-2 Spike (Trimer) IgG or IgM ELISA (Thermo Fisher) was utilized to assess the quantity of IgG or IgM antibodies that had bound to the SARS-CoV-2 Spike (Trimer). The study revealed that there was no statistically significant difference between the vaccines (P value = 0.958). The investigation further demonstrated that all three vaccines (Pfizer, AstraZeneca and Sinopharm) were effective in stimulating the production of IgM and IgG. The study revealed that Sinopharm demonstrated superior efficacy in the induction of IgM and IgG. The utilization of ChAdOx1 resulted in the generation of higher levels of IgG compared to BNT162b2, as evidenced by a statistically significant difference (P value= 0.0001). The enhanced immune response observed with Sinopharm could be attributed to its nature as an inactivated subunit vaccine. The immunological reactions to the vaccines studied in the following studies have prompted a lot of issues about how they happen, and the study recommends more studies regarding the most effective vaccines among the Kurdish people in the Kurdistan Region of Iraq.