Abstract
Background: Adaptive immune response to infection with SARS-CoV-2 comprises antibody response as well as T cell response. Population-based serosurveys provide a method for estimating infection rates and monitoring the response of the immune system to help elucidate population immunity.
Methods: In June 2020 we tested 835 participants comprising almost half of the population of an Austrian township. We determined the seroprevalence of SARS-CoV-2, and symptoms correlated with prior infection. In two additional studies with patients recovering from COVID-19 in October and December 2020 we determined SARS-CoV-2-specific immunoglobulin A (IgA) and IgG levels (IgG), as well as specific T cell activities.
Results: At baseline, 9% of our population tested seropositive for IgA (75/835) and IgG (71/835), respectively. We identified 6 major symptoms (anosmia/ageusia, weight loss, anorexia, general debility, dyspnea, fever), which in combination were of high prognostic value for predicting COVID-19 infections. In patients after COVID-19 infection at 4 months follow-up IgA and IgG levels were stable. At 6 months follow-up, 97% of previous COVID-19 cases tested positive for IgA, IgG or T cell activity with 63% testing positive for all of them. A lasting immune response was positively correlated with disease severity.
Conclusions: We found a high baseline seroprevalence of SARS-CoV-2 infections in an Austrian township. Specific adaptive immune response remained detectable after 6 months in vast majority of patients recovering from COVID-19.
Footnotes
Cite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA3803.
This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2021
