Dear Dr. Belhassen-García,

Thank you very much for submitting your manuscript "New circulation of genotype V of Crimean-Congo haemorrhagic fever virus in humans from Spain." for consideration at PLOS Neglected Tropical Diseases. As with all papers reviewed by the journal, your manuscript was reviewed by members of the editorial board and by several independent reviewers. The reviewers appreciated the attention to an important topic. Based on the reviews, we are likely to accept this manuscript for publication, providing that you modify the manuscript according to the review recommendations.

Please prepare and submit your revised manuscript within 30 days. If you anticipate any delay, please let us know the expected resubmission date by replying to this email.  

When you are ready to resubmit, please upload the following:

[1] A letter containing a detailed list of your responses to all review comments, and a description of the changes you have made in the manuscript. 

Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out

[2] Two versions of the revised manuscript: one with either highlights or tracked changes denoting where the text has been changed; the other a clean version (uploaded as the manuscript file).

Important additional instructions are given below your reviewer comments.

Thank you again for your submission to our journal. We hope that our editorial process has been constructive so far, and we welcome your feedback at any time. Please don't hesitate to contact us if you have any questions or comments.

Sincerely,

Dennis A. Bente, D.V.M., Ph.D.

Deputy Editor

PLOS Neglected Tropical Diseases

Dennis Bente

Deputy Editor

PLOS Neglected Tropical Diseases

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Reviewer's Responses to Questions

Key Review Criteria Required for Acceptance?

As you describe the new analyses required for acceptance, please consider the following:

Methods

-Are the objectives of the study clearly articulated with a clear testable hypothesis stated?

-Is the study design appropriate to address the stated objectives?

-Is the population clearly described and appropriate for the hypothesis being tested?

-Is the sample size sufficient to ensure adequate power to address the hypothesis being tested?

-Were correct statistical analysis used to support conclusions?

-Are there concerns about ethical or regulatory requirements being met?

Reviewer #1: (No Response)

Reviewer #2: An retrospective epistudy of sera was collected from various areas in Spain from folks that had any clinical presentations included in a typical CCHF case definition. These sera were screened using various antigenic and nucleic methods (ELISA/PCR/Sanger etc.,) which revealed four retrospective cases of CCHF. The virus was interestingly typed to the European clade, suggesting that both circulating African clade and European clade viruses were present and infecting both ticks and humans within Spanish borders.

Methods are appropriate for the study aims. This reviewer would recommend to including the type of reagents used in the in-house ELISA and IFA assay used for detection? What were the antigens or antibodies utilized as well as the methodologies?

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Results

-Does the analysis presented match the analysis plan?

-Are the results clearly and completely presented?

-Are the figures (Tables, Images) of sufficient quality for clarity?

Reviewer #1: Results are clearly presented and decision workflow for positive and negative samples clearly laid out.

Reviewer #2: (No Response)

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Conclusions

-Are the conclusions supported by the data presented?

-Are the limitations of analysis clearly described?

-Do the authors discuss how these data can be helpful to advance our understanding of the topic under study?

-Is public health relevance addressed?

Reviewer #1: Conclusions are supported.

Reviewer #2: (No Response)

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Editorial and Data Presentation Modifications?

Use this section for editorial suggestions as well as relatively minor modifications of existing data that would enhance clarity. If the only modifications needed are minor and/or editorial, you may wish to recommend “Minor Revision” or “Accept”.

Reviewer #1: (No Response)

Reviewer #2: Accept, however, minor editing throughout would enhance clarity; this reviewer recommends having the manuscript submitted to an English/grammar proofreading service.

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Summary and General Comments

Use this section to provide overall comments, discuss strengths/weaknesses of the study, novelty, significance, general execution and scholarship. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. If requesting major revision, please articulate the new experiments that are needed.

Reviewer #1: Manuscript is well written with only minor editing for grammar and clarity needed. Authors interestingly identified a novel strain of CCHFV that until now was not known to be circulating in Spain. This conclusions is well supported by their phylogenetic analysis which strongly argues against this identified strain being a descendant of already known strains in Spain. Their data also suggests multiple introductions of CCHFV into Spain, an important finding that highlights the continued spread of CCHFV.

Minor comments:

The positive acute case was associated with cattle husbandry and the virus clusters with Turkey, Kosovo and Russian strains of CCHFV. Is there any movement of cattle between these regions and does the patient have any history of travel to these regions? If not can authors speculate on how CCHFV from this region spread to Spain? Are there migratory birds that travel between these regions? Livestock trade?

Patient population presented with an undifferentiated febrile illness and only one patient was positive for CCHFV. Do authors have any data on what the rest of the patients had?

Line 288 is missing a reference.

Authors state that their qRT-PCR was modified to include an internal control. What was this control?

Reviewer #2: This work represents very forward thinking clinical sciences. It is of great relevance to the geographic area in terms of understanding the past and likely future burden of clinical CCHF.

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Reviewer #1: No

Reviewer #2: No

Figure Files:

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email us at figures@plos.org.

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Reproducibility:

To enhance the reproducibility of your results, PLOS recommends that you deposit laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see http://journals.plos.org/plosntds/s/submission-guidelines#loc-materials-and-methods

Dear Dr. Belhassen-García,

We are pleased to inform you that your manuscript 'New circulation of genotype V of Crimean-Congo haemorrhagic fever virus in humans from Spain.' has been provisionally accepted for publication in PLOS Neglected Tropical Diseases.

Before your manuscript can be formally accepted you will need to complete some formatting changes, which you will receive in a follow up email. A member of our team will be in touch with a set of requests.

Please note that your manuscript will not be scheduled for publication until you have made the required changes, so a swift response is appreciated.

IMPORTANT: The editorial review process is now complete. PLOS will only permit corrections to spelling, formatting or significant scientific errors from this point onwards. Requests for major changes, or any which affect the scientific understanding of your work, will cause delays to the publication date of your manuscript.

Should you, your institution's press office or the journal office choose to press release your paper, you will automatically be opted out of early publication. We ask that you notify us now if you or your institution is planning to press release the article. All press must be co-ordinated with PLOS.

Thank you again for supporting Open Access publishing; we are looking forward to publishing your work in PLOS Neglected Tropical Diseases.

Best regards,

Michael R Holbrook, PhD

Associate Editor

PLOS Neglected Tropical Diseases

Dennis Bente

Deputy Editor

PLOS Neglected Tropical Diseases

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