-->PONE-D-25-62563-->-->Feasibility of establishing a serosurveillance system using residual specimens from district-level hospitals: A case study in Choma and Ndola Districts of Zambia-->-->PLOS One

Dear Dr. Mutembo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Specifically, as stated by the first reviewer if the manuscript concludes that the system is feasible, but it would be stronger to provide a few simple quantitative indicators to support the conclusion. A short chapter untitled lesson learned migh help to highlight the key point of a successfull study using this "used remnent samples".-->-->

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Pierre Roques, Ph.D.

Academic Editor

PLOS One

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Reviewers' comments:

Reviewer's Responses to Questions

-->Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. -->

Reviewer #1: Partly

Reviewer #2: Yes

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

Reviewer #1: N/A

Reviewer #2: N/A

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-->3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.-->

Reviewer #1: Yes

Reviewer #2: No

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-->4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.-->

Reviewer #1: Yes

Reviewer #2: Yes

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-->5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)-->

Reviewer #1: Dear Editor,

Thank you for the opportunity to review this manuscript. The topic is important and the idea of using residual specimens for serosurveillance is interesting, especially in low-resource settings. The paper is clear and well written overall.

However, I have a few concerns that should be addressed before publication.

Feasibility outcomes: the manuscript concludes that the system is feasible, but it would be stronger to provide a few simple quantitative indicators (for example, number of eligible samples per day, proportion excluded, missing data rate for key variables, and basic information on workload/time). Even descriptive metrics by site would help.

Sampling strategy and duplicates: the daily “systematic sampling” approach should be described more precisely (how were samples selected during the day?). Also, the definition of duplicates (2-week window) is pragmatic but needs a brief justification, and ideally the number of duplicates excluded.

Data availability: the current statement (“available upon request”) may not fully match the journal data sharing policy. Please clarify what data can be shared and how (even a de-identified dataset or limited variables).

Minor comments:

Please check Table 1 layout to make totals easier to read.

A short paragraph summarizing the main “lessons learned” (Table 2) in the Discussion could improve readability.

In summary, I think this work is valuable, but I recommend major revision to strengthen the feasibility assessment and improve clarity on sampling and data sharing.

Sincerely,

Reviewer #2: 1-OUI. Le manuscrit présente une étude de faisabilité bien conçue avec des objectifs clairs, des méthodes appropriées et une collecte systématique de données à travers trois hôpitaux. La combinaison d’observations directes, de cartographie des processus et de consultations structurées avec les parties prenantes est méthodologiquement solide et appliquée de manière cohérente. Les données rapportées (par exemple, le nombre d’échantillons dans le tableau 1, le flux de travail dans la Figure 1 et les leçons dans le tableau 2) soutiennent directement les principales conclusions selon lesquelles la collecte des échantillons résiduels est faisable mais nécessite des ajustements opérationnels pour la scalabilité. Les auteurs sont prudents dans l’interprétation de leurs conclusions, reconnaissent les limites, et évitent de surestimer la généralisation. Dans l’ensemble, l’étude est techniquement rigoureuse, et les conclusions sont bien étayées par les preuves fournies.

2- N/A

Il s’agit d’une étude descriptive de faisabilité axée sur les flux de travail opérationnels et la collecte de spécimens dans trois hôpitaux. Aucune analyse statistique formelle n’est prévue ni requise, car le manuscrit ne vise pas à tester des hypothèses ni à estimer les tailles d’effet. Les résultats reposent sur des observations qualitatives, la cartographie des processus, des consultations avec le personnel et des décomptes sommaires simples (par exemple, les spécimens collectés par groupe d’âge et site dans le tableau 1). L’absence de statistiques inférentielles est appropriée pour ce type de recherche axée sur la mise en œuvre, et les données descriptives fournies suffisent à étayer les conclusions. Des contextes supplémentaires, tels que les proportions des échantillons exclus ou les distributions de temps de flux de travail, pourraient améliorer la clarté mais n’affectent pas la validité globale des résultats.

3- NON ; Je recommande aux auteurs soit de fournir des tableaux résumés anonymisés ou des extraits dans les informations de soutien, soit de spécifier un point de contact indépendant pour un accès afin de mieux s’aligner sur la politique de la revue.

4- OUI ; Le manuscrit est clairement rédigé et bien structuré, suivant un flux logique. Les termes techniques sont utilisés de manière appropriée et cohérente, et le texte est entièrement intelligible pour un public international.

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Do you want your identity to be public for this peer review?  For information about this choice, including consent withdrawal, please see our Privacy Policy.-->

Reviewer #1: No

Reviewer #2: No

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Feasibility of establishing a serosurveillance system using residual specimens from district-level hospitals: A case study in Choma and Ndola Districts of Zambia

PONE-D-25-62563R1

Dear Dr. Mutembo,

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.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Pierre Roques, Ph.D.

Academic Editor

PLOS One

Additional Editor Comments (optional):

Sorry for the delay of the final acceptation

Reviewers' comments:

Reviewer's Responses to Questions

-->Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.-->

Reviewer #3: All comments have been addressed

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-->2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. -->

Reviewer #3: Yes

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-->3. Has the statistical analysis been performed appropriately and rigorously? -->

Reviewer #3: N/A

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-->4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.-->

Reviewer #3: Yes

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-->5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.-->

Reviewer #3: Yes

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-->6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)-->

Reviewer #3: Given this is a second round of review, I have compared the original manuscript to the revised version, and looked at the responses to the reviewer comments. My conclusion is that the authors have addressed all specific comments raised by the primary reviewers. The manuscript is now technically sound, formatted according to journal requirements, and provides a clear, scalable roadmap for serosurveillance in resource-constrained settings. I recommend this manuscript for immediate acceptance.

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-->7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review?  For information about this choice, including consent withdrawal, please see our Privacy Policy.-->

Reviewer #3: Yes:  Michelo Simuyandi

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