Is Higher Viral Load in SARS-CoV-2 Associated With Death?

Abstract

Abstract Background There is no proven prognostic marker or adequate number of studies in patients hospitalized for coronavirus disease 2019 (COVID-19). Methods We conducted a retrospective cohort study of patients hospitalized with COVID-19 from March 14 to June 17, 2020, at São Paulo Hospital. SARS-CoV-2 viral load was assessed using the cycle threshold (Ct) values obtained from an RT-PCR assay applied to the nasopharyngeal swab samples. Disease severity and patient outcomes were compared. Results Among the 875 patients, 50.1% (439/875) had mild, 30.4% (266/875) moderate, and 19.5% (170/875) severe disease. A Ct value of <25 (472/875) indicated a high viral load, which was independently associated with mortality (OR: 0,34; 95% CI: 0,217–0,533; p < 0.0001). Conclusions Admission SARS-CoV-2 viral load is an important surrogate biomarker of infectivity and is independently associated with mortality among patients hospitalized with COVID-19.