Longitudinal\nAssessment of Nasopharyngeal Biomarkers\nPost-COVID-19: Unveiling Persistent Markers and Severity Correlations

SARS-CoV-19 infection\nprovokes a variety of symptoms;\nmost patients\npresent mild/moderate symptoms, whereas a small proportion of patients\nprogress to severe illness with multiorgan failure accompanied by\nmetabolic disturbances requiring ICU-level care. Given the importance\nof the disease, researchers focused on identifying severity-associated\nbiomarkers in infected patients as well as markers associated with\npatients suffering long-COVID. However, little is known about the\npresence of biomarkers that remain a few years after SARS-CoV-2 infection\nonce the patients fully recover of the symptoms. In this study, we\nevaluated the presence of persistent biomarkers in the nasopharyngeal\ntract two years after SARS-Cov-2 infection in fully asymptomatic patients,\ntaking into account the severity of their infection (mild/moderate\nand severe infections). In addition to the direct identification of\nseveral components of the Coronavirus Infection Pathway in those individuals\nthat suffered severe infections, we describe herein 371 proteins and\ntheir associated canonical pathways that define the different adverse\neffects of SARS-CoV-2 infections. The persistence of these biomarkers\nfor up to two years after infection, along with their ability to distinguish\nthe severity of the infection endured, highlights the surprising presence\nof persistent nasopharyngeal exudate changes in fully recovered patients.