PONE-D-20-14072

Evaluation of Community Based Surveillance in the Rohinya refugee camps in Cox's Bazar, Bangladesh, 2019

PLOS ONE

Dear Dr. van Boetzelaer,

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Jennifer Yourkavitch

Academic Editor

PLOS ONE

Additional Editor Comments:

Please address all reviewer comments. Please also indicate if data used in the analysis are available, i.e., the underlying data from the surveillance system are not in the manuscript or supplemental files.

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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: No

Reviewer #2: Yes

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

Reviewer #1: N/A

Reviewer #2: Yes

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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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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 Authors,

Congratulations for your hard work in setting up and operating a large community-based surveillance system in this emergency setting. Due to its scale and its context, I strongly believe the description of this system in the literature would be of important interest.

I read your manuscript with attention, but I still struggle with some specifics of how the system was operated, but mainly with its results. I would like to understand how many cases were detected because of the household visits, or how many cases were first detected through the household visits in comparison with the detected cases in the routine healthcare facility system. At the moment, it is still not clear to me.

Also, I consider this paper rather as a description of the system and its results, than as a proper dedicated evaluation of the system which would have needed the collection of dedicated data to inform pre-defined evaluation indicators. I don’t think it is a problem, a description is already of great interest, I would just suggest replacing all instances of “evaluation” by “description”.

Please find below detailed comments and proposed modifications for your consideration, I hope they may be useful.

Best regards,

Title:

* Consider the replacement of the term “Evaluation” by “Description”: i.e. “Description of Community Based Surveillance […]”, indeed the paper provides a description of the structure and several attributes of the surveillance system put in place and of its results, rather than a proper dedicated evaluation with pre-planned methodology and use of dedicated evaluation indicators.

Abstract:

* Line 25: replace “evaluated” by “described” as it seems no additional data was collected to specifically “evaluate” the performance of the CBS system in comparison with a set of pre-defined evaluation indicators.

* Line 30: not clear if these cholera cases were identified by the CBS system, by the healthcare facilities, or by both.

* Line 37: there is a need to know how many cases were detected solely by health facility surveillance and how many through CBS to be able to make a conclusion on the value of the CBS system, see below comments for additional details.

Background:

* Lines 55-57: from references 3 to 7 only reference 5 relates with the assertion that “[CBS] has been shown to facilitate early detection of epidemic prone diseases […]." The other references relate either to systems focused on mortality and nutritional status (3,4) or healthcare facility based systems (6,7). Thus, please remove the incorrect references to the claim and consider rewording it as “It may facilitate” instead of “It has been shown to facilitate”.

* Line 73: consider removing “evaluate” from “We describe and evaluate”.

Figure 1:

* Consider introducing the figure later in the methods section once some concepts such as EWARS tool have been described.

* Define all acronyms in the footnote, e.g. AWD: acute watery diarrhoea; WHO-led JAT investigation.

* On the arrow before "referral of suspected case to nearest health facility" specify that it is done if it has been considered a suspect case by the visiting team.

* Discrepancy with information lines 103-104 where all suspect cases were referred by the surveillance worker to the healthcare facility OR the figure 1 is misleading (lines 103-104: "Surveillance workers referred all suspected cases of disease to the nearest health facility and recorded the household number to inform further case investigations by the Epi Alert Team or Medical Response Team”).

* Consider rewording "Upload case information suspected case on EWARS (weekly)" to "Weekly upload of case information on EWARS".

* Did you have an RDT for AFP? I guess this was only for cholera and hepatitis E, to be corrected.

Methods:

* Provide a dedicated section on the surveillance workers: what were their recruitment criteria, which training was provided, for how long, on which topics, which refreshers?

* It is not clear which data you used for the descriptions provided in the results section, for example which source of data you used for the number of cases identified by health care facilities? Please describe which data you used and how you analysed it.

* Line 87: could the comparison with the camps without CBS have been considered?

* Lines 87-88: “Each surveillance cycle encompassed four weeks” can be removed here as it will be described later and we don’t know yet what you mean by “surveillance cycle”.

* Lines 93-97: Consider rewording "[…] data were collected on active case finding for specific epidemic prone diseases" to "[…] data were collected by active case finding of specific epidemic prone diseases, [...]". See also comment lines 106-111.

* Lines 103-104: discrepancy with figure 1, see comment above in Figure 1.

* Lines 106-111: merge with lines 93-97, but it would be even better to remove these paragraphs and replace them by a table with a comprehensive list of the collected variables, or to expand figure 3 to include the collected variables, or to provide a copy of the collecting form. You can also consider moving this list of collected data to the section currently named “Data analysis and reporting” (lines 138-145).

* Lines 123-124: specify the modalities of the household visits: was a surveillance worker alone during the visits? Or they were two surveillance workers per visit?

* Lines 128-129: How many surveillance workers per team leader?

* Lines 138-145: Consider renaming the section “Data analysis and reporting” to “Data entry and data analysis” and put it after the section “Alert and Response” to ease its understanding (for example lines 143-145 there was no prior mention of data collected by the Epi Alert Team and the Medical Response teams).

* Lines 139-140: It is not clear which data was entered in an electronic system and how. When you list the variables collected (see previous comments), can you specify if data has been entered in an electronic system (such as Excel spreadsheets), how (specific data entry mask or not), if it was done through a single or double entry, and if it was done through dedicated data entry staff or other staff on top of their other duties.

* Lines143-145: please specify which data is collected by the Epi Alert Team and Medical Response teams and how, you can provide the link to the supplementary material 1.

* Lines 155-156: need to quickly describe the EWARS system, or at least put the current reference 10.

* Lines 180-181: in Figure 1 it is mentioned that case-based data (line lists) were entered in the EWARS system weekly. Did healthcare facilities perform data entry in Excel in addition to the entry in EWARS? If yes, by whom and please discuss why.

* Lines 190-191: “ Firstly, the epidemiologists reported the probable cases of Cholera

and Hepatitis E into the EWARS mechanism”, discrepancy with figure 1 or unclear statement: in figure 1 such action is performed if probable case of cholera and hepatitis E but also of AFP and clusters of AJS and AWD.

* Line 194: “icddr,b” acronym, can you modify this acronym to remove the comma in it and put some capital letters to help the reader?

Table 1:

* I understand you used the same case definitions at healthcare facility level and for the community health workers.

* Yet, these are very difficult case definitions for community workers , e.g. terms such as "anorexia", "sclera", "focal weakness or paralysis" or paraclinic criteria: e.g. "leukopenia".

* Please specify why dedicated definitions for community workers were not used while available in international guidance (see list of existing case definitions for CBS in the "Data collection" section of the following document https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6461245/bin/pone.0215278.s002.pdf from https://dx.doi.org/10.1371%2Fjournal.pone.0215278.

* Please discuss your choice of using the same case definitions for CBS in healthcare facilities in the discussion section.

Table 3:

* The reference is wrong, the CDC guidance has been published in 2001, not in 2012.

* Please put the attributes and “measurement” in the same order as in the result section and remove any attribute/measurement you don’t describe in the result section.

* Please put the data you used for each measurement instead of excerpts from the CDC guidance.

* Sensitivity attribute: the “verification of each suspected case identified by the CBS at the health facility level” would not help to assess the sensitivity of the system; the only way to assess this sensitivity would have been to first undertake a dedicated study to detect all cases really occurring in the area of interest (which, I imagine, would not have been feasible).

Results:

* Provide a short description of the surveillance workers: numbers, demographics (age, sex), literacy level.

* Do you have data on the number of cases identified by healthcare facilities without referral by CBS, and the number of cases referred by CBS?

* Lines 233-234, Figures 4 to 7: this is very unclear:

* If I understand well, your Epi Alert Team is sent to the household to check the suspect case reported by the community health worker. If I am correct, this "Epi Alert Team" is then part of your CBS system and it makes no sense to present a "Epi Alert Team" curve in addition to the "CBS" curve. "CBS curve" that should be the current "Epi Alert Team curve".

* How can the "Health facilities" curve be below the "Epi Alert Team" or "CBS" curves while all CBS suspect cases were expected to be referred to the health facility and thus be registered there? Please provide more information regarding the data collection and analysis process of these "Health facilities suspect cases".

* Lines 245-255: you should present here the usefulness of the CBS system in addition to the routine healthcare facility system. Do you have any data regarding how many cases were referred to the healthcare facilities because of the CBS system? (And how many were identified in the healthcare facilities without being referred by the CBS system).

* Lines 267-269: “The CBS supplemented the health facility based surveillance as it helped to identify suspected cases of disease early, and to ensure timely referral of suspected cases to health facilities for

diagnostics and treatment.” I don’t see any result supporting this claim, please provide some data to support it, or you need to remove it.

* Line 271: Timeliness: the main indicator would have been the delay between onset of symptoms and identification to see if CBS managed to identify suspect cases earlier.

* Lines 273-275: please rephrase to "the main difference is the delay between the identification of a suspected case and the notification of the epidemiologist and Epi Alert Team or Medical Response Team through health facility based surveillance versus through CBS".

* Lines 288-289: “While this surveillance system generated data that informed programming and enabled early detection of epidemic prone disease […]”, please provide data to support this claim, or remove it.

* Lines 292-298: Please put this section regarding training in the methods.

Table 5:

* Again it is not clear what the referral process was. Any suspect case by community surveillance workers were referred for case management even if the case was not verified by the EPI alert team? Here, all the suspect cases have a public health action performed even if they are discarded by the Epi Alert team or the Medical Response Team. Please explain.

Table 6:

* Why is there only data on AWD cases?

Discussion:

* Lines 325-327: “ This evaluation shows that the CBS system and the alert and response mechanism allowed for timely detection and response to cases of epidemic prone diseases”: which results support this claim?

* Lines 346-348: the reason why you couldn’t assess the sensitivity of the system was that you couldn’t know the real occurrence of the cases in the area, not that you couldn’t check that the suspect cases were true positives.

* Lines 350-352: the fact that the population under surveillance is different between the CBS system and the healthcare facility system is very important and should be emphasized in the methods section and taken into consideration in the results.

* Lines 411-416: Please specify for which indicator under surveillance the lack of proper denominator was a problem, and which consequences it had. For example, regarding the detection of acute infectious diseases, this was not a problem as the objective was to early detect and early respond to first cases to avoid an outbreak.

* Lines 420-426: while I agree with the general conclusion, I don't see in this paper clear results regarding the additional number of cases that were identified by CBS in comparison to the healthcare facility system.

Reviewer #2: This is a clearly written article with technically rigorous rationale, methods, findings, and conclusions.

In the data quality/validity section, I suggest the authors add more explanation to help the reader interpret the graphs, which is (if my interpretation is correct): that, in addition to the trends being similar, that the CBS consistently identified more cases. But when verified by the Epi Alert Team or Medical Response Team the numbers of suspected cases were similar to that of the health facility system. The possible exception may be AJS, but those numbers were fewer relative to other suspected cases.

I appreciate the authors and the journal's willingness to publish not-positive findings. That said, there could have been a number of positive externalities of the CBS system that are not captured by the 'number of suspected' cases data. The result of the system in terms of referral of CHWs, water and sanitation, and ability of health services to respond to community needs/opinions could have a overall positive health effect. Based on their knowledge of the situation, perhaps the authors have a hypothesis of how to re-organize services and/or better coordinate services with other actors based on this experience, one that is not as focused on the CBS system.

Minor comment: on lines 379-380, suggest the authors specify which data were lacking (assume it was costing data?). On the other hand, given the findings, one might conclude that it is not necessary to conduct any costing study.

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Reviewer #1: Yes: Jose Guerra

Reviewer #2: No

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PONE-D-20-14072R1

Evaluation of Community Based Surveillance in the Rohinya refugee camps in Cox's Bazar, Bangladesh, 2019

PLOS ONE

Dear Dr. van Boetzelaer,

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.

Please submit your revised manuscript by Dec 31 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
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• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Jennifer Yourkavitch

Academic Editor

PLOS ONE

Additional Editor Comments (if provided):

Thank you for your attention to the reviewers' comments. There are a few more issues to address.

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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 #1: (No Response)

Reviewer #2: 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 #1: Partly

Reviewer #2: Yes

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

Reviewer #1: Yes

Reviewer #2: Yes

**********

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 #1: Yes

Reviewer #2: Yes

**********

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 #1: Yes

Reviewer #2: Yes

**********

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 #1: Dear Authors,

I think the paper is much clearer now, thank you for your commitment.

I believe this paper should be published, this is an important experience which involved a lot of resources including hundreds of committed colleagues during an extended period of time.

I just have two major issues that I think should be taken into consideration before publication and few minor comments.

**Major issues:**

* **Data quality / validity evaluation attribute**:

* In Table 3, the measurement modality for the "Data quality / validity evaluation attribute" is stated as "Comparison of trends of health facility surveillance (gold standards) and community based surveillance trends".

* The fact is that **you can't compare these trends as they don't have the same population under surveillance**.

* You correctly say it in the discussion lines 357-360: "While the trends of reported suspected cases from all the components of the surveillance system were similar, and could be an indicator of data quality and validity, **it must be noted that the catchment population of the CBS and health facility surveillance differed** as the health facilities were also visited by patients who did not live in the CBS catchment area."

* In any case, **it is misleading to evaluate this "Data quality / validity" attribute, as you have no data to do it.**

* Lines 240-249: when you compare the "Surveillance worker curve" and the "Epi alert team curve", you are not evaluating the "data quality/validity" but the evolution of the PPV. The assertion "The trend comparison per disease show that surveillance workers identified the most suspected cases” makes no sense here, due to your design, indeed the surveillance workers will always detect more suspect cases that the Epi or Response teams (who are coming after a case has been detected by the surveillance worker).

* Please consider the following actions:

* Abstract line 25, methods line 215, Table 3, results lines 240-249: **remove the data quality/validity attribute** as it cannot be evaluated (see above).

* **From lines 241-249, you can move the following slightly rephrased sentence and figures 4 to 7 to the PPV results section**: "Available health facility surveillance data from two MSF health facilities and data from the CBS (suspected cases identified by the surveillance workers and verified by the Epi Alert Team) are shown for AWD, AJS, Diphtheria and measles (Figure 4-7)."

* **CBS case definitions**:

* **CBS workers mostly used the exact same case definitions for suspect cases that at the health facility**, as correctly mentioned lines 182-184: " The same diseases that were included in the CBS were under surveillance at the health facilities using the same MSF case definitions (Table 1)."

* **These were not "community case definitions" as the term is generally understood.** For example, the following ones are community case definitions: acute jaundice: “Any person with a sudden yellowing of the skin for not more than two weeks, with or without elevated body temperature.”; Acute flaccid paralysis: “Any child with a sudden onset of acute paralytic disease." (2014 WHO guide: https://www.afro.who.int/sites/default/files/2017-06/a-guide-for-establishing-community-based-surveillance-102014_0.pdf ). Other examples of guides providing such "community case definitions": Integrated Diseases Surveillance and Response in the African Region. Community-based Surveillance (CBS) Training Manual. WHO, 2015.; Community-based surveillance: guiding principles. IFRC, 2017.; Technical Guidelines for Integrated Disease Surveillance and Response in the African Region; WHO and US CDC, 2010.

* To avoid any misunderstanding, please consider the following actions:

* Line 101: **Replace** "The CBS system used community case definitions (Table 1)" by "The CBS system used standard case definitions (Table 1)".

* Table 1: **Replace column titles**: "CBS case definition (suspected)" by "Case definitions used by CBS surveillance workers" and "Health facility case definition" by "Case definitions used at health facility".

* You may, or not, discuss around lines 347-353 how using "community case definitions" could have improved the ability of community volunteers to detect true disease.

**Minor issues**:

* Abstract line 35 and Discussion line 335:

* "The CBS allowed for timely detection and response [...]". Indeed timely response is correct, but for timely detection this doesn't seem correct: visits were only on a monthly basis and you don't have data on the delay between onset of symptoms and detection.

* Consider rephrasing the sentence to "The CBS allowed for timely response [...]".

* Figure 1:

* You mention in your reply that "We have moved the figure with the overview of the surveillance system to the end of the ‘methods’ section, line 204, as suggested". But, you have not, it is still referred line 73 and its mention doesn't appear later on.

* To clarify that surveillance workers referred to the health facilities and that Epi and Response team reminded visited patients to go to the health facility, consider modifying in the figure: “Referral by Epi Alert Team […]” by “Epi Alert Team or Medical Response Team reminded suspected cases to visit the nearest health facility”.

* “Weekly upload of case information suspected case on EWARS” is unclear, consider “Weekly upload of case information on EWARS” OR “Weekly upload of information on suspected cases on EWARS”.

* Line 58: the wording “Some CBS train community volunteers to use actively search for cases of pre-defined case definition [...]” is unclear, consider the following rewording: "Some CBS train community volunteers to actively search for cases using pre-defined case definitions […]."

* In your reply you mention: "We have added that the households were visited by ‘a surveillance worker’ (single)". But, you have not, only “surveillance workers” (plural) is mentioned in the 4 occurrences of “surveillance workers” visiting households. Consider correcting these four occurrences.

* The number of surveillance workers per team leader is currently mentioned in the results section (line 306), consider moving it to the Methods section, potentially in table 2.

* Figures 4 to 7: you need to add different line types (or use different colours) so that it is easy to understand which line represents what.

* Line 396: don't use the acronym HR, but the full wording: "human resources" (if this is what HR meant).

Reviewer #2: Thank you for your responses. I am satisfied with your responses have met the considerations I had provided and of the other review.

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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 #1: Yes: José Guerra

Reviewer #2: No

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Attachments

Attachment

Submitted filename: review2.pdf

Evaluation of Community Based Surveillance in the Rohinya refugee camps in Cox's Bazar, Bangladesh, 2019

PONE-D-20-14072R2

Dear Dr. van Boetzelaer,

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