The University of Louisville Journal of Respiratory Infections


Some patients recover from COVID-19, but their reverse transcription-polymerase chain reaction (RT-PCR) for SARS-CoV-2 remains persistently positive. In the evaluation of these patients, it is important to define the cycle threshold (Ct) value of the RT-PCR test. This article will present a case study, address relevant findings and interpretation of the RT-PCR test, and explain the use of Ct values in defining when a healthcare worker may return to work. Our current approach is to allow health care workers with persistently positive RT-PCR to return to work if the Ct value is greater than 35.


The author(s) received no specific funding for this work.



Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.



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