Abstract
BACKGROUNDThe COVID-19 vaccines currently in use require 2 doses to achieve optimal protection. Currently, there is no indication as to whether individuals who have been exposed to SARS-CoV-2 should be vaccinated, or whether they should receive 1 or 2 vaccine doses.METHODSWe tested the antibody response developed after administration of the Pfizer/BioNTech vaccine in 124 health care professionals, of whom 57 had a previous history of SARS-CoV-2 exposure with or without symptoms.RESULTSPostvaccine antibodies in SARS-CoV-2-exposed individuals increased exponentially within 5 to 18 days after the first dose compared to naive subjects (P < 0.0001). In a multivariate linear regression (LR) model we showed that the antibody response depended on the IgG prevaccine titer and on the exposure to SARS-CoV-2. In symptomatic SARS-CoV-2-exposed individuals, IgG reached a plateau after the second dose, and those who voluntarily refrained from receiving the second dose (n = 7) retained their antibody response. Gastrointestinal symptoms, muscle pain, and fever markedly positively correlated with increased IgG responses. By contrast, all asymptomatic/paucisymptomatic and unexposed individuals showed an important increase after the second dose.CONCLUSIONOne vaccine dose is sufficient in symptomatic SARS-CoV-2-exposed subjects to reach a high titer of antibodies, suggesting no need for a second dose, particularly in light of current vaccine shortage.TRIAL REGISTRATIONClinicalTrials.gov NCT04387929 .FUNDINGDolce & Gabbana and the Italian Ministry of Health (Ricerca corrente).
Keywords: Adaptive immunity; Immunoglobulins; Immunology; Vaccines.
【저자키워드】 immunology, Adaptive immunity, Vaccines, immunoglobulins, 【초록키워드】 antibodies, SARS-CoV-2, IgG, Vaccine, COVID-19 vaccine, antibody, Antibody Response, Symptoms, vaccine dose, Health, symptomatic, Fever, Pain, Gastrointestinal, Linear regression, Care, Pfizer/BioNTech, administration, dose, IgG responses, subject, second dose, first dose, individual, professionals, Ministry of Health, Italian, tested, receiving, reached, individuals, retained, the antibody response, receive, positively correlated, 【제목키워드】 COVID-19, antibody, SARS-CoV-2 vaccine, symptomatic, dose, individual, increase,