TY - JOUR
T1 - Large‐Scale Study of Antibody Titer Decay Following BNT162b2 mRNA Vaccine or SARS‐CoV‐2 Infection
AU - Israel, Ariel
AU - Shenhar, Yotam
AU - Green, Ilan
AU - Merzon, Eugene
AU - Golan‐cohen, Avivit
AU - Schäffer, Alejandro A.
AU - Ruppin, Eytan
AU - Vinker, Shlomo
AU - Magen, Eli
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2022/1/1
Y1 - 2022/1/1
N2 - Immune protection following either vaccination or infection with SARS‐CoV‐2 is thought to decrease over time. We designed a retrospective study, conducted at Leumit Health Services in Israel, to determine the kinetics of SARS‐CoV‐2 IgG antibodies following administration of two doses of BNT162b2 vaccine, or SARS‐CoV‐2 infection in unvaccinated individuals. Antibody titers were measured between 31 January 2021, and 31 July 2021 in two mutually exclusive groups: (i) vaccinated individuals who received two doses of BNT162b2 vaccine and had no history of previous infection with COVID‐19 and (ii) SARS‐CoV‐2 convalescents who had not received the vaccine. A total of 2653 individuals fully vaccinated by two doses of vaccine during the study period and 4361 convalescent patients were included. Higher SARS‐CoV‐2 IgG antibody titers were observed in vaccinated individuals (median 1581 AU/mL IQR [533.8–5644.6]) after the second vaccination than in convalescent individuals (median 355.3 AU/mL IQR [141.2–998.7]; p < 0.001). In vaccinated subjects, antibody titers decreased by up to 38% each subsequent month while in convalescents they decreased by less than 5% per month. Six months after BNT162b2 vaccination 16.1% subjects had antibody levels below the seropositivity threshold of <50 AU/mL, while only 10.8% of convalescent patients were below <50 AU/mL threshold after 9 months from SARS‐CoV‐2 infection. This study demonstrates individuals who received the Pfizer‐BioNTech mRNA vaccine have different kinetics of antibody levels compared to patients who had been infected with the SARS‐CoV‐2 virus, with higher initial levels but a much faster exponential decrease in the first group.
AB - Immune protection following either vaccination or infection with SARS‐CoV‐2 is thought to decrease over time. We designed a retrospective study, conducted at Leumit Health Services in Israel, to determine the kinetics of SARS‐CoV‐2 IgG antibodies following administration of two doses of BNT162b2 vaccine, or SARS‐CoV‐2 infection in unvaccinated individuals. Antibody titers were measured between 31 January 2021, and 31 July 2021 in two mutually exclusive groups: (i) vaccinated individuals who received two doses of BNT162b2 vaccine and had no history of previous infection with COVID‐19 and (ii) SARS‐CoV‐2 convalescents who had not received the vaccine. A total of 2653 individuals fully vaccinated by two doses of vaccine during the study period and 4361 convalescent patients were included. Higher SARS‐CoV‐2 IgG antibody titers were observed in vaccinated individuals (median 1581 AU/mL IQR [533.8–5644.6]) after the second vaccination than in convalescent individuals (median 355.3 AU/mL IQR [141.2–998.7]; p < 0.001). In vaccinated subjects, antibody titers decreased by up to 38% each subsequent month while in convalescents they decreased by less than 5% per month. Six months after BNT162b2 vaccination 16.1% subjects had antibody levels below the seropositivity threshold of <50 AU/mL, while only 10.8% of convalescent patients were below <50 AU/mL threshold after 9 months from SARS‐CoV‐2 infection. This study demonstrates individuals who received the Pfizer‐BioNTech mRNA vaccine have different kinetics of antibody levels compared to patients who had been infected with the SARS‐CoV‐2 virus, with higher initial levels but a much faster exponential decrease in the first group.
KW - Antibody titer
KW - BNT162b2 mRNA vaccine
KW - SARS‐CoV‐2 infection
UR - http://www.scopus.com/inward/record.url?scp=85122137411&partnerID=8YFLogxK
U2 - 10.3390/vaccines10010064
DO - 10.3390/vaccines10010064
M3 - Article
C2 - 35062724
AN - SCOPUS:85122137411
SN - 2076-393X
VL - 10
JO - Vaccines
JF - Vaccines
IS - 1
M1 - 64
ER -