Abstract:
Among the unknowns in decoding the pathogenesis of SARS-CoV-2 persistent symptoms in Long Covid is whether there is a contributory role of abnormal immunity during acute infection – some have proposed that Long Covid may be a consequence of either an excessive or inadequate initial response. We analysed SARS-CoV-2 humoral and cellular immunity in healthcare workers infected during the first wave.
Symptom questionnaires allowed stratification into those with persistent symptoms and those without for comparison. During the period up to 18-weeks post-infection, we observed no difference in antibody responses to spike, RBD or nucleoprotein, virus neutralisation, or T cell responses. Also, there was no difference in the profile of antibody waning.
Analysis at 1-year, after two vaccine doses, comparing those with persistent symptoms to those without, again showed similar SARS-CoV-2 immunity. Thus, quantitative differences in SARS-CoV-2 adaptive immunity during acute infection are unlikely to contribute to Long Covid causality.
Source: Altmann D, Reynolds C, Joy G, et al. Persistent symptoms after COVID-19 during the first wave are not associated with differential immunity to SARS-CoV-2. Research Square; 2022. DOI: 10.21203/rs.3.rs-2324777/v1. https://www.researchsquare.com/article/rs-2324777/v1 (Full text)