Objective: Although the adaptive immune response to SARS-CoV-2 has been characterised in the acute and early convalescent phase of the disease, few studies explore whether natural infection elicits long-lasting immunological memory in recovered individuals. In this work, we aimed to assess the maintenance of immunological memory to SARS-CoV-2.
Methods: We evaluated the long-term virus-specific cellular and humoral immune response in the members of an Italian Serie A football team, who experienced a cluster of COVID-19 in March 2020, which was strictly evaluated in the following months.
Results: Our results highlight a heterogeneous magnitude of immunological memory at 5 months after infection. Indeed, 20% of the subjects displayed a weak cellular and humoral memory to SARS-CoV-2, suggesting that they may be at higher risk of reinfection. In addition, a history of symptomatic COVID-19 was associated with higher levels of SARS-CoV-2-reactive CD4+ T cells and specific antibody levels than in asymptomatic individuals.
Conclusion: Collectively, these data demonstrate that immunity to SARS-CoV-2 is maintained five months postinfection even if the magnitude of response is heterogeneous among individuals. This finding suggests that some COVID-19-recovered subjects may benefit from vaccination.
Keywords: SARS‐CoV‐2; T cells; immunoglobulins; immunological memory.
© 2021 The Authors. Clinical & Translational Immunology published by John Wiley & Sons Australia, Ltd on behalf of Australian and New Zealand Society for Immunology, Inc.