Background The long-term course of immunity among individuals with a history of COVID-19, in particular among those who received a booster vaccination, has not been well defined so far. Methods SARS-CoV-2-specific antibody levels were measured by ELISA over 1 year among 136 health care workers infected during the first COVID-19 wave and in a subgroup after booster vaccination approximately 1 year later. Furthermore, spike-protein-reactive memory T cells were quantified approximately 7 months after the infection and after booster vaccination. Thirty healthy individuals without history of COVID-19 who were routinely vaccinated served as controls. Results Levels of SARS-CoV-2-specific IgM- and IgA-antibodies showed a rapid decay over time, whereas IgG-antibody levels decreased more slowly. Among individuals with history of COVID-19, booster vaccination induced very high IgG- and to a lesser degree IgA-antibodies. Antibody levels were significantly higher after booster vaccination than after recovery from COVID-19. After vaccination with a two-dose schedule, healthy control subjects developed similar antibody levels as compared to individuals with history of COVID-19 and booster vaccination. SARS-CoV-2-specific memory T cell counts did not correlate with antibody levels. None of the study participants suffered from a reinfection. Conclusions Booster vaccination induces high antibody levels in individuals with a history of COVID-19 that exceeds by far levels observed after recovery. SARS-CoV-2-specific antibody levels of similar magnitude were achieved in healthy, COVID-19-naïve individuals after routine two-dose vaccination. Supplementary Information The online version contains supplementary material available at 10.1007/s15010-021-01703-9.
【저자키워드】 COVID-19, SARS-CoV-2, cellular immunity, Antibody-mediated immunity, SARS-CoV-2-vaccination, 【초록키워드】 IgG, IgM, vaccination, Health care, Immunity, antibody, T cells, Infection, ELISA, Reinfection, T cell, Health care worker, antibody levels, memory T cell, antibody level, booster vaccination, supplementary material, subject, healthy control, individual, Study participants, specific IgM, cell count, memory T, controls, Course, Result, defined, healthy, magnitude, induce, suffered, significantly higher, Level, were measured, healthy individual, study participant, quantified, 【제목키워드】 follow-up study,