Dependence of the severity of the course of COVID-19 on viral load in hospitalized patients

Abstract

Clinical manifestations of COVID-19 vary in different patients from asymptomatic to severe multiple organ failure. The aim of this study was to analyze the severity of COVID-19 in hospitalized patients depending on the initial viral load of SARS-CoV-2. Study included 156 patients 18 years old and more. In the RT-PCR test, viral load was assessed by amplification cycle threshold Ct. The result was considered positive for Ct values < 40 and negative for Ct ≥ 40. 3 groups of 52 people each with different trajectories of the course of the disease were identified: 1 — mild, 2 — moderate, 3 — severe/fatal. The values of the median Ct cycle threshold upon admission of patients in group 3 to the hospital were significantly lower, indicating higher initial levels of viral RNA in patients with more severe disease. This pattern persisted over a 28-day period, and it was in this 3 group that higher levels of viral RNA were detected throughout the time compared to other disease trajectories. In conclusion, the effect of the initial SARS-CoV-2 viral load and its dynamics during hospitalization on the severity of COVID-19 is shown. This parameter can be a prognostic marker for assessing the clinical condition of patients during treatment.