Related Experiment Video
Updated: Aug 14, 2025

Live Imaging and Quantification of Viral Infection in K18 hACE2 Transgenic Mice Using Reporter-Expressing Recombinant SARS-CoV-2
Published on: November 5, 2021
Repeated COVID-19 Relapse of an Imported Patient Infected with SARS-CoV-2 Delta Variant of Concern
Background:
Repeated re-positive of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) B.1.617.2 (Delta) variants of concern (VOC) in recovered coronavirus disease 2019 (COVID-19) patients have not been reported yet.
Methods:
We reported a rare case of repeated COVID-19 relapse during the post-discharge surveillance.
Results:
This case had long-term viral shedding for 79 days.
Conclusions:
This case highlights that longer observation and isolation periods need be considered for patients with SARS-CoV-2 delta VOC infection.
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