Khảo sát nồng độ kháng thể kháng miền liên kết thụ thể của SARS-CoV-2 sau tiêm 2 mũi vắc xin phòng COVID-19 trên đối tượng nhân viên y tế của trường Đại học Y Hà Nội

Vaccination against COVID-19 is considered as the most effective way to prevent the spread and mitigate the consequences of the COVID-19 pandemic. However, in order to ensure the effectiveness of vaccination, monitoring and evaluation of the effect of vaccines to produce antibodies are always important. In this study, we evaluated the antibody concentration against the receptor-binding domain (RBD) of SARS-CoV-2 after 2 doses of COVID-19 vaccine on medical staffs at the Hanoi Medical University. There were 66 out of 68 (97.06%) study participants whose anti-RBD antibody concentration of SARS-CoV-2 reached the threshold that could make convalescent plasma products with high antibody titers according to the criteria of Food and Drug Administration (FDA) standards. The average anti-RBD antibody concentration of SARS-CoV-2 of the group receiving 2 doses of AZD1222 (AstraZeneca) vaccine and the group receiving at least 1 dose of BTN162b2 (Pfizer) vaccine were 1202.33 and 4312.92 U/mL, respectively. In a total of 56 study subjects who received 2 doses of AZD1222 vaccine, we found a decrease in the anti-RBD antibody concentration of SARS-CoV-2 in the group that received the 2nd dose over 90 days compared to the group under 90 days (p=0.044). At the same time, we did not find an association between adverse effects and anti-RBD antibody concentration of SARS-CoV-2 after the AZD1222 vaccination. These results once again emphasize the effectiveness of the vaccination campaign in Vietnam, as well as contribute to the importance of deploying booster vaccinations to ensure the maintenance of the protective effectiveness of the vaccine.