Comparison of Antibody Levels Produced by Pfizer, AstraZeneca, and Sinopharm Vaccination in COVID-19 Patients in Erbil City-Iraq

Abstract

In this study, early adverse impacts that emerged after vaccination with each dose of these vaccines were compared with previously infected participants. Ant-SARS-CoV-2 spike-specific IgG and IgA antibodies produced by these three vaccines have been assessed using the ELISA method at different time periods; including pre-vaccination, and post-vaccination with Pfizer-BioNTech, AstraZeneca, and Sinopharm vaccine. Overall, 150 previously infected cases were studied, 50 cases received the Pfizer vaccine, 50 cases received the AstraZeneca vaccine, and 50 cases received the Sinopharm vaccine. The findings showed that a higher number of vaccinated participants with AstraZeneca and Pfizer vaccines had tiredness/fatigue/lethargy, headache, fever, and soreness in the arm at the first shot, but milder adverse effects, such as headaches, fever, and soreness in the arm, were detected in the data on the Sinopharm vaccine's adverse impacts. At the second dose, a lower number of vaccinated cases with AstraZeneca, and Pfizer vaccines reported higher frequencies of the side effects. However, the results showed that the level of anti-spike-specific IgG and IgA antibodies produced by vaccinated patients with the Pfizer vaccine increased compared to those who were vaccinated with AstraZeneca and Sinopharm vaccine from 25 days after the first dose. From 30 days after the second dose, the IgG and IgA antibodies were significantly boosted in 97% of vaccinated patients with the Pfizer vaccine compared to 92% of those who were vaccinated with AstraZeneca vaccines, and 60% of those who were vaccinated with Sinopharm. In conclusion, these results confirmed that two doses of the Pfizer, and AstraZeneca vaccines induce a higher response of IgG and IgA antibodies than that induced by Sinopharm vaccines.