PONE-D-24-25703The added diagnostic value of RT-PCR on faeces for the diagnosis of COVID-19PLOS ONE

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Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: I Don't Know

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

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Reviewer #1: This study showed that combining SARS-CoV-2 RT-PCR testing on fecal samples (FS) with upper respiratory tract samples (URTS) increased COVID-19 diagnoses by 31.8%. Hence, the authors claim that adding FS testing may enhance detection in patients with negative URTS results but high clinical suspicion of COVID-19.

The paper is well-written and deserves consideration. However minor revision is required:

-Table 1, detailing patients' characteristics, is missing.

-Have the authors used a validated assay to perform RT-PCR testing on fecal samples?

-The authors should expand the discussion regarding: the capacity of standard laboratories to perform RT-PCR on fecal samples and the potential delayed positivity of RT-PCR on fecal samples compared to upper respiratory tract testing.

Reviewer #2: The authors presented results that confirmed that use of RT_PCR on fecal samples improves overall diagnostic accuracy. However, this manuscript should qualify as a short communication going by the small dataset used to arrive at this conclusion. Also, the statement provided under the objective appears ambiguous. Authors should make it clearer.

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Reviewer #1: No

Reviewer #2: Yes:  Ayodele Oluwaseun Ajayi

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The added diagnostic value of RT-PCR on faeces for the diagnosis of COVID-19

PONE-D-24-25703R1

Dear Dr. Van der Moeren,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Kind regards,

Vishwanatha R. A. P. Reddy

Academic Editor

PLOS ONE