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Updated: Dec 7, 2025

Efficient SARS-CoV-2 Quantitative Reverse Transcriptase PCR Saliva Diagnostic Strategy utilizing Open-Source Pipetting Robots
Published on: February 11, 2022
Patients with mild and general COVID-19 should be negative for at least 3 consecutive nucleic acid tests before
Rui Lu1, Tianhui Huang2, Haiqing Hu1
1Department of Orthopedics, Wuhan Third Hospital, Tongren Hospital of Wuhan University, Wuhan, PR China.
Abstract:
Given the global spread of coronavirus disease (COVID-19), strict discharge standard is of great significance for the prevention and control of the epidemic, thus, the purpose of this study is to formulate more strict and scientific discharge standards. A total of 845 patients with mild and general COVID-19 who were considered to be discharged from hospital were included in this study. The median time from the onset of COVID-19 to the occurrence of two consecutive negative nucleic acid tests of these patients was 21 days. 223 of the 845 patients were tested again after two consecutive negative nucleic acid tests and 17.49% of the patients were positive. Moreover, 82.51% (184 of 223) of these patients experienced negative results from three consecutive nucleic acid tests, the median time from the onset of COVID-19 to the occurrence of three consecutive negative nucleic acid tests was 23 days (range: 3-56 days), and 38 of which were further tested after three consecutive negative nucleic acid tests, while about 5.26% (2 of 38) patients showed positive nucleic acid test results. Thus, we suggested that the patient should be negative for at least 3 consecutive nucleic acid tests before discharge, and the test time should be no earlier than the 23rd day since the onset of the disease.
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