PONE-D-20-40463

Detailed disease progression of 213 patients hospitalized with Covid-19 in the Czech Republic: An exploratory analysis

PLOS ONE

Dear Dr. Modrak,

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Reviewers' comments:

Reviewer #1: The authors have provided an overview of COVID-19 hospitalized patients in the Czech Republic. The study is well-written in a proper English language and fashion, also, with quite dynamic scientific flow. The study cohort is rather small. However, there are few major concerns that should be clarified by the authors.

1. The "Introduction section" contains misleading information - Remdesivir is no longer available in only limited amounts of patients. Remdesivir is currently one of the front-line therapies.

2. The authors should explain why are the patients treated mostly with hydroxychloroquine despite only low clinical benefit (mentioned in the Introduction).

3. Table 1 should contain the total number of deaths. Also, the number of hydroxychloroquine treated patients is missing.

4. Given the presented data, it is clear that by the time of this study, the majority of patients was treated with either hydroxychloroquine or azithromycin. This has fundamentally changed during the past few months. The majority of patients is receiving dexamthasone and remdesivir, while in this study, the proportions are only 2%, and 1%, respectively.

This might imply two things:

either the included institutions have no access to first-line therapies or the included institutions are not following the treatment guidelines. Does this really reflect the treatment of COVID-19 patients in the Czech Republic in 2021? If so,

that is very disturbing.

At this point I believe that the authors have several options. They might collect a new up-to-date cohort and correlate the treatment strategies and outcomes of now and then. That would significantly improve the quality of the manuscript. In that case the manuscript title could reffer to "disease progression of patients hospitalized in the Czech R."

Other option is to highlight that these data are on the efficacy of hydroxychloroquine in the treatment of COVID-19 which was applied at the very beginning of the COVID pandemic. In such case, the manuscript title must change. Also the Introduction section should provide more data on hydroxychloroquine and the reasons for its application and also the study cohort should be presented as "remdesivir-naive" or dexamethasone-naive" which could be actually beneficial for the observation of hydroxychloroquine treatment of patients. Since Hydroxychloroquine is being used in a wide range of autoimmune diseases, the immune background of COVID-19 should be included. This study, however, cannot be titled as it currently stands. The title and the abstract must change.

5. The authors should at least discuss the current first-line treatments of COVID-19 in the Czech Republic and reffer to pertinent guidelines.

Reviewer #2: This study aimed at significant COVID-related health problems.

However, this study requires extensive revisions.

1. The organization of the text is complicated. The structure of this paper is far from a standard scientific article.

2. The sampling methods are unclear. The authors should clearly define sampling methods, research centers included in this study, characteristics of hospitals - single wards? or all hospitals were dedicated to COVID-19? Moreover, the timeline of the patients' enrolment of participants should be clearly defined.

3. More information about the COVID-19 pandemic in the Czech Republic is needed. Moreover, the Authors should present data on the organization of COVID-19 dedicated treatment.

4. Conclusions seem to be not supported by the results.

Reviewer #3: I like the general idea of this manuscript and find it interesting to the readers of Plos One. However, the conclusion section is very short and does not contain any references. I suggest rewriting the conclusion section and discussing your results in detail with reference to similar studies

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Disease progression of 213 patients hospitalized with Covid-19 in the Czech Republic in March - October 2020: An exploratory analysis

PONE-D-20-40463R1

Dear Dr. Modrak,

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,

Aleksandar R. Zivkovic

Academic Editor

PLOS ONE