Abstract
Background: There are limited data directly comparing immune responses to vaccines and to natural infections with coronavirus disease 2019 (COVID-19). This study assessed the immunogenicity of the BNT162b2 and ChAdOx1 nCoV-19 vaccines over a 3-month period and compared the immune responses with those to natural infections.
Method: We enrolled healthcare workers who received BNT162b2 or ChAdOx1 nCoV-19 vaccines and patients with confirmed COVID-19 and then measured S1 immunoglobulin (Ig) G and neutralizing antibodies and T-cell responses.
Results: A total of 121 vaccinees and 26 patients with confirmed COVID-19 were analyzed. After the second dose, the BNT162b2 vaccine yielded S1 IgG antibody responses similar to those achieved with natural infections (mean IgG titer [standard deviation], 2241 [899] vs 2601 [5039]; P = .68) but significantly stronger than responses to the ChAdOx1 vaccine (174 [96]; P < .001). The neutralizing antibody titer generated by BNT162b2 was 6-fold higher than that generated by ChAdOx1 but lower than that by natural infection. T-cell responses persisted for 3 months with BNT162b2 and natural infection but decreased with ChAdOx1.
Conclusions: Antibody responses after the second dose of BNT162b2 are higher than after the second dose of ChAdOx1 and like those occurring after natural infection. T-cell responses are maintained longer in BNT162b2 vaccinees than in ChAdOx1 vaccinees.
Keywords: BNT162b2; COVID-19; ChAdOx1 nCoV-19; T cells; antibody; second dose.
【저자키워드】 COVID-19, antibody, T cells, BNT162b2, ChAdOx1 nCoV-19, second dose., 【초록키워드】 coronavirus disease, neutralizing antibody, IgG, Vaccine, BNT162b2 vaccine, immune response, Antibody Response, T-cell Response, healthcare worker, infections, Immunoglobulin, response, Patient, ChAdOx1 vaccine, natural infection, ChAdOx1, T-cell responses, ChAdOx1 nCoV-19 vaccine, Neutralizing antibody titer, second dose, vaccinees, S1 IgG, vaccinee, enrolled, analyzed, significantly, of BNT162b2, 【제목키워드】 response, ChAdOx1 nCoV-19, natural, over, Period,