Is preexisting immunity to seasonal coronaviruses limited to cross-reactivity with SARS-CoV-2? A seroprevalence cross-sectional study in north-eastern France

Abstract

In light of the ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), there remain unanswered questions regarding the humoral immune response and the breadth of cross-reactivity with preexisting seasonal human coronaviruses (HCoVs). Initially, the lack of preexisting immunity was believed to contribute to the virus's rampant spread. Several studies reported that the clinical manifestations of COVID-19 are age-dependent, with children appearing to be less susceptible to infection and severe disease [1]. This highlighted the potential cross-protective effect of preexisting immunity to seasonal HCoVs. However, reported data on cross-reactivity was contradictory, antigen-dependent, and mostly conducted on small sample sizes.