In this study, we tested the hypothesis that the immunosenescence profile could account for the disproportional susceptibility of the elderly to severe forms of COVID-19. The immunological profiles of volunteers residing in endemic and non-endemic areas for chronic infectious diseases were analyzed at the early stage of SARS-CoV-2 infection. A unique signature of inflammatory plasma mediators was identified in COVID-19 volunteers when compared to individuals with other flu-like syndromes. COVID-19 severity correlated with high levels of inflammatory mediators
among them, CXCL9, a serum marker of aging. Patients who progressed to hospitalization displayed high frequencies of CD8