Serological study of CoronaVac vaccine and booster doses in Chile: immunogenicity and persistence of anti-SARS-CoV-2 spike antibodies
Journal
BMC Medicine
ISSN
1741-7015
Date Issued
2022
Author(s)
Leonardo Vargas
Nicolás Valdivieso
Fabián Tempio
Valeska Simon
Daniela Sauma
Lucía Valenzuela
Caroll Beltrán
Loriana Castillo-Delgado
Ximena Contreras-Benavides
Mónica L. Acevedo
Rafael I. Gonzalez
Fernando Valiente-Echeverría
Ricardo Soto-Rifo
Mario Rosemblatt
Mercedes Lopez
Fabiola Osorio
María Rosa Bono
Type
Resource Types::text::journal::journal article
URL Institutional Repository
Abstract
<jats:title>Abstract</jats:title><jats:sec>
<jats:title>Background</jats:title>
<jats:p>Chile was severely affected by COVID19 outbreaks but was also one of the first countries to start a nationwide program to vaccinate against the disease. Furthermore, Chile became one of the fastest countries to inoculate a high percentage of the target population and implemented homologous and heterologous booster schemes in late 2021 to prevent potential immunological waning. The aim of this study is to compare the immunogenicity and time course of the humoral response elicited by the CoronaVac vaccine in combination with homologous versus heterologous boosters.</jats:p>
</jats:sec><jats:sec>
<jats:title>Methods</jats:title>
<jats:p>We compared the immunogenicity of two doses of CoronaVac and BNT162b2 vaccines and one homologous or heterologous booster through an ELISA assay directed against the ancestral spike protein of SARS-CoV-2. Sera were collected from individuals during the vaccination schedule and throughout the implementation of homologous and heterologous booster programs in Chile.</jats:p>
</jats:sec><jats:sec>
<jats:title>Results</jats:title>
<jats:p>Our findings demonstrate that a two-dose vaccination scheme with CoronaVac induces lower levels of anti-SARS-CoV-2 spike antibodies than BNT162b2 in a broad age range (median age 42 years; interquartile range (IQR) 27-61). Furthermore, antibody production declines with time in individuals vaccinated with CoronaVac and less noticeably, with BNT162b2. Analysis of booster schemes revealed that individuals vaccinated with two doses of CoronaVac generate immunological memory against the SARS-CoV-2 ancestral strain, which can be re-activated with homologous or heterologous (BNT162b2 and ChAdOx1) boosters. Nevertheless, the magnitude of the antibody response with the heterologous booster regime was considerably higher (induction fold BNT162b2: 11.2x; ChAdoX1; 12.4x; CoronaVac: 6.0x) than the responses induced by the homologous scheme. Both homologous and heterologous boosters induced persistent humoral responses (median 122 days, IQR (108-133)), although heterologous boosters remained superior in activating a humoral response after 100 days.</jats:p>
</jats:sec><jats:sec>
<jats:title>Conclusions</jats:title>
<jats:p>Two doses of CoronaVac induces antibody titers against the SARS-CoV-2 ancestral strain which are lower in magnitude than those induced by the BNT162b2 vaccine. However, the response induced by CoronaVac can be greatly potentiated with a heterologous booster scheme with BNT162b2 or ChAdOx1 vaccines. Furthermore, the heterologous and homologous booster regimes induce a durable antibody response which does not show signs of decay 3 months after the booster dose.</jats:p>
</jats:sec>
<jats:title>Background</jats:title>
<jats:p>Chile was severely affected by COVID19 outbreaks but was also one of the first countries to start a nationwide program to vaccinate against the disease. Furthermore, Chile became one of the fastest countries to inoculate a high percentage of the target population and implemented homologous and heterologous booster schemes in late 2021 to prevent potential immunological waning. The aim of this study is to compare the immunogenicity and time course of the humoral response elicited by the CoronaVac vaccine in combination with homologous versus heterologous boosters.</jats:p>
</jats:sec><jats:sec>
<jats:title>Methods</jats:title>
<jats:p>We compared the immunogenicity of two doses of CoronaVac and BNT162b2 vaccines and one homologous or heterologous booster through an ELISA assay directed against the ancestral spike protein of SARS-CoV-2. Sera were collected from individuals during the vaccination schedule and throughout the implementation of homologous and heterologous booster programs in Chile.</jats:p>
</jats:sec><jats:sec>
<jats:title>Results</jats:title>
<jats:p>Our findings demonstrate that a two-dose vaccination scheme with CoronaVac induces lower levels of anti-SARS-CoV-2 spike antibodies than BNT162b2 in a broad age range (median age 42 years; interquartile range (IQR) 27-61). Furthermore, antibody production declines with time in individuals vaccinated with CoronaVac and less noticeably, with BNT162b2. Analysis of booster schemes revealed that individuals vaccinated with two doses of CoronaVac generate immunological memory against the SARS-CoV-2 ancestral strain, which can be re-activated with homologous or heterologous (BNT162b2 and ChAdOx1) boosters. Nevertheless, the magnitude of the antibody response with the heterologous booster regime was considerably higher (induction fold BNT162b2: 11.2x; ChAdoX1; 12.4x; CoronaVac: 6.0x) than the responses induced by the homologous scheme. Both homologous and heterologous boosters induced persistent humoral responses (median 122 days, IQR (108-133)), although heterologous boosters remained superior in activating a humoral response after 100 days.</jats:p>
</jats:sec><jats:sec>
<jats:title>Conclusions</jats:title>
<jats:p>Two doses of CoronaVac induces antibody titers against the SARS-CoV-2 ancestral strain which are lower in magnitude than those induced by the BNT162b2 vaccine. However, the response induced by CoronaVac can be greatly potentiated with a heterologous booster scheme with BNT162b2 or ChAdOx1 vaccines. Furthermore, the heterologous and homologous booster regimes induce a durable antibody response which does not show signs of decay 3 months after the booster dose.</jats:p>
</jats:sec>
Cite this document
Vargas, L., Valdivieso, N., Tempio, F., Simon, V., Sauma, D., Valenzuela, L., Beltrán, C., Castillo-Delgado, L., Contreras-Benavides, X., Acevedo, M. L., Acevedo, J., Gonzalez, R. I., Valiente-Echeverría, F., Soto-Rifo, R., Rosemblatt, M., Lopez, M., Osorio, F., & Bono, M. R. (2022). Serological study of CoronaVac vaccine and booster doses in Chile: Immunogenicity and persistence of anti-SARS-CoV-2 spike antibodies. BMC Medicine, 20(1), 216. https://doi.org/10.1186/s12916-022-02406-0
Subjects
antibodies
;
booster
;
covid-19
;
vaccination
;
adult
;
antibodies, viral
;
bnt162 vaccine
;
chile
;
covid-19
;
covid-19 vaccines
;
humans
;
sars-cov-2
;
coronavac
;
coronavirus spike glycoprotein
;
tozinameran
;
virus antibody
;
adult
;
antibody production
;
article
;
blood sampling
;
comparative study
;
coronavirus disease 2019
;
enzyme linked immunosorbent assay
;
female
;
human
;
humoral immunity
;
immunogenicity
;
immunological memory
;
male
;
serology
;
severe acute respiratory syndrome coronavirus 2
;
vaccination
;
virus strain
;
chile
;
epidemiology
;
prevention and control