Antibody responses to mRNA versus non-mRNA COVID vaccines among the Mongolian population

Enkhbold Sereejav; Ankhbayar Sandagdorj; Purevbat Bazarjav; Sarangua Ganbold; Altansukh Enkhtuvshin; Naranzul Tsedenbal; Bayasgalan Namuuntsetseg; Khishigmunkh Chimedregzen; Darmaa Badarch; Dashpagma Otgonbayar; Bayarzaya Artbazar; Oyunsuren Enebish; Erdembileg Tsevegmid; Huricha Baigude; Uyanga Batzorig; Bumdelger Batmunkh; Baigalmaa Jantsansengee; Chinbayar Tserendorj; Bayarsaikhan Dorjderem; Bilegtsaikhan Tsolmon; Tsogzolmaa Ganbold

doi:10.1016/j.ijregi.2023.05.002

Antibody responses to mRNA versus non-mRNA COVID vaccines among the Mongolian population

IJID Reg. 2023 Sep:8:1-8. doi: 10.1016/j.ijregi.2023.05.002. Epub 2023 May 14.

Authors

Enkhbold Sereejav¹, Ankhbayar Sandagdorj², Purevbat Bazarjav^{2

3}, Sarangua Ganbold², Altansukh Enkhtuvshin², Naranzul Tsedenbal², Bayasgalan Namuuntsetseg², Khishigmunkh Chimedregzen², Darmaa Badarch², Dashpagma Otgonbayar², Bayarzaya Artbazar⁴, Oyunsuren Enebish¹, Erdembileg Tsevegmid¹, Huricha Baigude³, Uyanga Batzorig⁵, Bumdelger Batmunkh², Baigalmaa Jantsansengee², Chinbayar Tserendorj², Bayarsaikhan Dorjderem², Bilegtsaikhan Tsolmon², Tsogzolmaa Ganbold²

Affiliations

¹ Ministry of Health, Ulaanbaatar, Mongolia.
² National Center for Communicable Diseases, Ulaanbaatar, Mongolia.
³ Inner Mongolia University, Hohhot, China.
⁴ World Health Organization, Ulaanbaatar, Mongolia.
⁵ University of California, San Diego, California, USA.

Abstract

Background: A nationwide vaccination program against coronavirus disease 2019 (COVID-19) was started in Mongolia 4 months after the first local transmission, which occurred in November 2020. Previous studies have reported that two doses of COVID-19 vaccine result in increased antibody against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A study was conducted in Mongolia 2 weeks after the second vaccine dose. In the present study, the serum levels of antibodies of individuals 6 months after natural SARS-CoV-2 infection were compared with those of individuals who had not been infected or had been infected but had received two doses of vaccine, including BNT162b2, ChAdOx1 n-CoV-19, Gam-COVID-Vac, and BBIBP-CorV, which were used for COVID-19 in Mongolia.

Methods: Of the 450 participants in this study, 237 (52.66%) were female and 213 (47.33%) were male. Four hundred people with or without SARS-CoV-2 infection who received two doses of 4 different COVID-19 vaccine participated in the vaccine groups and vaccine plus SARS-CoV-2 infection groups (50 in each group) and 50 individuals previously infected with SARS-CoV-2 participated in the unvaccinated group. Total antibody against SARS-CoV-2 infection, anti-SARS-CoV-2 N and S protein human IgG, and antibody inhibiting RBD-ACE2 binding were tested.

Results: In the BNT162b2 vaccine group, total antibody against SARS-CoV-2 remained constant until 6 months, while the other vaccine groups showed a significant decrease, as compared to the unvaccinated group. The level of anti-SARS-CoV-2 S-RBD protein IgG was significantly increased in the ChAdOx1 n-CoV-19, Gam-COVID-Vac, and BNT162b2 vaccines groups as compared to the unvaccinated group. Participants in the BNT162b2 vaccine group had higher ACE2 inhibition efficiency compared to the other vaccine groups as well as the unvaccinated group.

Conclusions: The BNT162b2 vaccine showed the highest level of antibody against SARS-CoV-2, followed by the BBIBP-CorV, Gam-COVID-Vac, and ChAdOx1 n-CoV-19 vaccines. The level of antibodies was increased in people infected with SARS-CoV-2 after vaccination, as compared to uninfected but vaccinated individuals.

Keywords: Antibody response; Binding inhibition; COVID-19; Severity; Vaccine.

Grants and funding

001/WHO_/World Health Organization/International