Publication details

Pokles hladiny neutralizačních protilátek po očkování proti SARS-CoV-2 u seniorů: výsledky observační studie v Jihomoravském kraji

Title in English Decreasing neutralization antibody levels following vaccination against SARS-CoV-2 in the elderly: an observational suty in Southern Moravia, Czech Republic


Year of publication 2022
Type Article in Periodical
Magazine / Source Epidemiologie, mikrobiologie, imunologie
MU Faculty or unit

Faculty of Medicine

Keywords covid-19;SARS-Cov-2;imunne response;antibody;vaccine
Description Introduction: Understanding the immune response after SARS-CoV-2 vaccination is essential to control the COVID-19 pandemic. Recent studies indicate that vaccine-induced humoral immunity may not be long-lasting and is weaker in the elderly. Methodology and sample: At the turn of June and July 2021, 653 seniors (426 women and 197 men with mean age of 74 years) were tested once for antibodies against SARS-Cov-2 in the South Moravian Region between 9 and 161 days after the second dose of vaccine (558 Pfizer -BioNTech, 28 Moderna, 36 AstraZeneca, 1 Johnson & Johnson). Two point-of-care iCHROMA™ II immunofluorescence assays were used: (1) COVID-19 Ab against mix of SARS-CoV-2 Nucleocapsid and Spike proteins (IgG Ab), and (2) COVID-19 nAb against S1-RBD protein (nAb). Results were analysed in relation to gender, age, vaccine, and past Covid-19 disease. Results: Our results show high variability of the antibody response, but indicate an overall relatively weak and decreasing antibody response in the first 6 months after vaccination. Only 58.4% (95% CI: 54.6-62.3) of subjects had positive nAb. The level of nAb decreased with time from vaccination - in the 4th and 5th month after vaccination, only 41.1% (95% CI: 30.9-51.3) and 15.4% (95% CI: 1.5-29.3), respectively. Vaccinees in older age groups, those vaccinated with AstraZeneca and naive individuals showed a lower antibody response. Conclusion: The antibody response to SARS-CoV-2 vaccination in the elderly was relatively weak and decreased in the first 6 months after vaccination. Although humoral immunity is complex and cellular immune memory is a key element of the humoral response after exposure to the wild virus, our results suggest that vaccine-induced humoral immunity may not be long-lasting. Elderly in the highest age groups and those who have not acquired natural SARS-CoV-2 infection are particularly at risk. This finding is relevant for adjusting vaccination strategies in selected population groups. More research into the antibody response and the complex immune response after vaccination against SARS-CoV-2 over longer time is needed.

You are running an old browser version. We recommend updating your browser to its latest version.

More info