Dynamics of Viral Shedding and Symptoms in Patients with Asymptomatic or Mild COVID-19
Seongman Bae, Ji Yeun Kim, So Yun Lim, Heedo Park, Hye Hee, Ji‐Soo Kwon, Mi Hyun Suh, Hyun Jung Lee, Joon Seo Lim, Jiwon Jung, Min Jae Kim, Yong Pil Chong, Sang‐Oh Lee, Sang‐Ho Choi, Yang Soo Kim, Ho Young Lee, SoHyun Lee, Man‐Seong Park, Sung‐Han Kim
Abstract
We conducted a prospective cohort study at a community facility designated for the isolation of individuals with asymptomatic or mild COVID-19 between 10 January and 22 February 2021 to investigate the relationship of viral shedding with symptom changes of COVID-19. In total, 89 COVID-19 adult patients (12 asymptomatic, 16 presymptomatic, 61 symptomatic) were enrolled. Symptom scores, the genomic RNA and subgenomic RNA of SARS-CoV-2 from saliva samples with a cell culture were measured. Asymptomatic COVID-19 patients had a similar viral load to symptomatic patients during the early course of the disease, but exhibited a rapid decrease in viral load with the loss of infectivity. Subgenomic RNA and viable virus by cell culture in asymptomatic patients were detected only until 3 days after diagnosis, and the positivity of the subgenomic RNA and cell culture in symptomatic patients gradually decreased in both from 40% in the early disease course to 13% at 10 days and 4% at 8 days after the symptom onset, respectively. In conclusion, symptomatic patients have a high infectivity with high symptom scores during the early disease course and gradually lose infectivity depending on the symptom. Conversely, asymptomatic patients exhibit a rapid decrease in viral load with the loss of infectivity, despite a similar viral load during the early disease course.