https://orcid.org/0000-0001-8235-5566
Peer Review History
| Original SubmissionMay 20, 2020 |
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PONE-D-20-15166 Epidemiological study on foot-and-mouth disease in small ruminants: sero-prevalence and risk factor assessment in Kenya PLOS ONE Dear Dr. Kairu-Wanyoike, 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. Details on the sampling procedure, sample size and descriptive analysis the number of animals that were vaccinated for FMD and those with clinical signs are lacking. Several parts of introduction, results and discussion are repeated throughout the text. Please submit your revised manuscript by Sep 20 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:
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Please do not edit.] 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 ********** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: No Reviewer #2: Yes ********** 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: Yes ********** 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 ********** 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: Comments of the authors General comments The study on ‘Epidemiological study on foot-and-mouth disease in small ruminants: sero-prevalence and risk factor assessment in Kenya’ is a good and useful study that documented the prevalence of the disease at national level and identified risk factors of the disease that can assist risk based surveillance and control intervention in Kenya. The study has collected quite large and fairly representative sample of the country’s small ruminant population that could generate reliable results. However the manuscript needs improvement in several ways and the following comments are forwarded to improve the manuscript The introduction is very long. Eight page introduction for research article is unusual. There is lack of clarity in in the sampling procedure and sample size determination. The sampling procedure is not clear. Specially the term ‘herd’ was defined in different ways and used inconsistently. This made difficult to understand how the multistage sampling method was used. It was not also clear why the sample size was determined independently for the two zones (PZ and SZ). The same inputs (parameters) were used in each zone and the same number of herds and animals were taken from each zone. If the interest was to stratify the sample, the nationally determined sample size could have been divided among the zones. The risk factor analysis was done using chi-square, and bivariable (I would suggest to name this univariable) and multivariable logistic regressions. If univariable logistic regression is done, the chi-square analysis is redundant and anything about chi-square in the manuscript should be removed. Looking in to that analysis even the univariable logistic regression is not important as it has not been used for screening the potential risk factor for the multivariable analysis. For that matter, given the adequate sample size, screening the variables is not needed and the univariable analysis can be ignored. Another problem with the analysis was; while the sampling procedure is cluster sampling, the analysis did not consider the sampling procedure. If cluster sampling is used there will underestimation of standard error (unwarranted significant p-values for regression coefficients) and this has to be taken care of. I would suggest use of mixed effect logistic regression with ‘herds’ and ‘villages’ as random effect variables for more reliable identification of factors associated with the disease. The result has unnecessary detail and redundant results. In line with the comments given in statistical analysis above, the chi-square test and the univariable analysis provides the same result and there is no any need to do the chi-square analysis. The univaraible logistic regression give more information like crude odds ratio for each category of the categorical variables which is not directly possible in the chi-square analysis. So I suggest anything related the chi-square analysis. Even the importance of the univariable analysis result should be re-considred. The discussion of the risk factor should be based on the significance of risk factors in the final multivariable model not on crude association seen from the univariable analysis. All the conclusions should be supported by the study findings which was not the case for some the recommendations The manuscript also needs improvement in the English. Specific Comments Abstract The abstract followed unstructured format. In this type format the abstract should be written in one paragraph. Line 33-32. No need of mentioning the statistical software in the abstract. Line 34-5. If logistic regression is done, the use chi-square for risk factor analysis will be redundancy Line 39 – 4 . Re -write it as “ the risk factors that were significantly positively associated with FMD sero-positivity in SR were being multipurpose (OR=1.150; p=0.034) and dairy (OR=2.029; p=0.003) production types.” Line 51…’carrier SR’…... Subclinical carrier? You didn’t have any result that showed SR are acting as carriers FMD. Introduction - The introduction is very long it has to be shortened to maximum of not more than 2-3 pages. E.g. the extensive discussion about differential diagnosis and the different diagnostic assays can be removed. The extensive description of the small ruminant production system in Kenya can be shorted and taken to material and methods part. The extensive discussion about the seroprevalence of SR FMD and production systems worldwide can be shortened or removed. Line 154. They ARE…… Line 166. Average HERD SIZE of sheep and goats Line 176. . Line 183. Is FMD important in sheep and goat as cause of production loss or for its epidemiological contributions for cattle? Just compare this with next paragraph (line 186-19) Lin 2011-15. Do these studies support your claim that trade costs are more important than direct cost of FMD for households? Do these SM keeper households participate international trade to countries that free of the disease? Line 226-230. The two sentences seem contradictory Materials and methods Line 248-9. ……………...since FMD is a transboundary disease and also transmitted through export of animals and animal products. Line 255-57. ‘The study targeted the sub location’ this is not clear. In epidemiology target population has its own technical meaning. The target population in this study is the national SR population. Rephrase this sentence to write what you mean. Line 252-7. Although the section title is study area, the text in this paragraph is more about study population Line 283. Sample size calculation was in two stages and per zone) IN EACH STRATUM: Line 286. Make clear what is in-contact farm Line 287 …………… “assuming a simple random sample of herds in each stratum independently” not clear Line 294 …………’simple random sample” SIMPLE RANDOM SAMPLING? But two line down it describes a cluster sampling in which first sub-locations are selected then household herds and then animals? Line 297. ‘323 sub-locations’. The 323 were herds which were defined as farms/in contact farms not sub-location! Again on next line it says “one village (herd)” and ‘”household herd per village”. Please make clear what herd is and use it consistently; not “herd” one time and “household herd’ another time unless they are meant different things. If the interest is to do stratified sampling the approach could have been determining the sample size using one of the sampling techniques (looks cluster sampling in this study case) and allocating the sample among the strata proportionally or if there reason not to allocate proportionally use other method of allocation. I couldn’t see the need to determine the sample size for the two strata independently as all the parameter used are the same for each stratum. Line 243. What are field freezers? Line 343 -344 . ‘One aliquot was used to test for the presence or absence of antibodies of Rift Valley Fever (RVF) and Peste de Petits Ruminants (PPR) antibodies according to the objective of the STSD project’ Give some explanation about this work and make clear that the present FMD work is a part or accompany of that work. Line 363-63. Rewrite the sentence avoiding repetitions and put the right reference for the test kit (product, Manufacture Company and place/country). Line 365-67 On the seropositivity/negativity to FMDV antibodies the outcome variables were categorised based on the on the results of the 3ABC blocking enzyme-linked immunosorbent assay. Line 367-73. The test procedure is not clearly documented. Revise the English. Line 390-94. Why was the herd level variables first entered to MS access (unlike the animal level variables which are directly entered to MS excel) before being brought to MS excel for data cleaning and coding? Line 402- To do this you need to document the se and sp of the test in the laboratory diagnosis section. Line 403- 433 statistical analysis part has lot of repetition and unnecessary detail. For example lin4 405-6 has the same idea with line 402-405 both of them are about crude association using chi-square. But few lines down it mention bivariable analysis is done. The chi- square test of comparison and bivariable analysis are the same and the chi-square is not needed for variables in considered in the bivariable logistic regressions The terminology bivariable is not correct has to be changed into univariable. The common usage is univariable and multivariable. It about the number of independent variables. If only one independent variable is included it is univariable and if more than one indnepenet variables is included it is multivariable. Line 434-36 The results of our study have been presented mainly in tables and figures and interpreted in text. Although the bivariable regression was carried out for all risk factors (individual animal and herd level) together, the results are in two tables to avoid too large a table. Other issues in this section; - The purpose the univariable analysis should be mentioned. - For goodness of it test, it is enough to mention what tests are used with appropriate reference. How each test measures goodness of fit is unnecessary detail. - In several places in this part the word’ interpretation’ is incorrectly used. For example specifying confidence interval level and P- values (419-20) or putting results in text (line 434-35) are not interpretations. Interpretations ae given meaning for you findings that is done in the discussion. Results Line 450. In M&M, the number of herds sampled was stated as 323 herds* 2 strata = 646 so how the herd number increased to 898. Line 451. Mention why the remaining samples were not available for testing Line 472. However a large proportion …… Line 482. Write in the full ideas instead of using “so” to make it clearer Line 496. What is the diffidence between communal grazing and mixed grazing Line 515-16. Sero-prevalence of a total of 7564 sera from the whole country was determined for the presence of non-structural FMDV protein (antibodies). Line 517. “Prevalence rate” Prevalence is not rate. Simply use prevalence (which known to be proportion). Correct this throughout the document. Line 518. if χ2 has to be reported it has to include the degrees of freedom like χ2(3), which means χ2 at 3 degrees of freedom. Do this throughout the manuscript Line 516. Write it as apparent prevalence as you have also true prevalence estimate Line 527. ‘Showed seronegativity’ is not good expression; state that prevalence in these counties is zero Line 530. Put the estimated true Seroprevalence in figure. Line 531-535. What does samplings sites represent, villages, individual herds or what? the map in figure 3 does not provide any information except the distribution of sampling sites. It should have indicate the negative sites as well. Moreover the legend and labels in the maps are not visible. Line 539 PAIR WISE Pearson correlation………… Line 539 …‘between county and production zone”….. No risk factor variable called ‘county type’ was mentioned in the list of variables indicated M&M part. Moreover test of collinearity is needed for the multivariable analysis. So this sentence should go down where multivariable results are documented. Another issue here is the use of the term ‘risk factor” should be replaced by “potential risk factor”. The variables are hypothesized to be a risk factor, not yet confirmed to be risk factor. They will be risk factor when they are found so after the analysis. So they should be referred to as potential risk factors thought out the document until they are confirmed. Line 546-47. Where is the result of the statistical analysis i.e. P-value Line 546-53. In this section it seems χ2 is used but in chi-square for comparison of three or more groups, it tells you only whether there is significant difference in the proportion/ prevalence among all groups. It doesn’t tell you between which pairs is the difference significant. So how can you come up with this results where the variables has three categories like breed (exotic, local, cross)? Line 554. Replace ‘the between herd prevalence’ with ‘herd level prevalence” Line 564. If it is not significant, why is it surprising? In the first place, in the result section just put what you find; such interpretation should be reserved for the discussion Line 566-71. The same comment as above in line 546-53. Line 604- 5. The result emphasis should be which factors are significantly associated with FMD seropositivty. Whether the association is positive or negative depends how the data was coded during analysis. For example, it is not sex that is negatively associated but it is being maleness. Line 604. Instead of table 5, S4 and S5 should be part of the main manuscript not supplementary. Line 612. S5 table attached is not about the herd level variables. Check whether the attached table is the right one. Line 612-13. The comparator should be mentioned. Line 627-8. The purpose of univaraible analysis is to screen the potential risk factors. If cut off p-value 0.2 does not reduce them small cut off should have been used. Actually given the very large sample size there was no need to screen in this study and univaraible analysis was not necessary. Line 645-76. Repetition of the table. Enough to mention the most salient results and leave the remaining detail to be referred from table Discussion Line 685. Delete ‘It is true’ and start with ‘According to this study …..’ Line 724-30. For SR age of 6 months and above can be considered as matured as they can be bred at this age and classification of mature above 1years of age is not appropriate. Hence it difficult to think these age animals (age 6 months – 1 year) will be kept at homestead and are less exposed to the disease. The observed higher prevalence in older animals could also be due cumulative seropositivity through repeated infection in their longer life time. Line 730. conversely Line 731. ‘Female posted’ change the word ‘posted’ with other more appropriate word Line 730-32. Both the univariable and the multivariable analysis showed females have significantly higher prevalence than males. Which result is being discussed here! Line 740 ‘….position…’ to mean explanation? Line 745. Change the word ‘contrary’ with the actual type purchase it self Line 749-50. not clear Line 755-59. Make it clearer Line 768. … three.. Line 784-95. Merge this discussion with preceding paragraphs. In the first place, what should be discussed is the result of the final model where confounding is controlled. It is meaningless to discuss the crude results of the chi-square or univariable analysis as these can’t correctly identify significant risk factors because of confounding. So the discussion in the preceding paragraphs should be adjusted accordingly. Conclusion Line 820-21. “The findings of this study give an understanding of the potential role of small ruminants in the epidemiology of FMD in Kenya and contribute to the global scenario’ Not exactly. It is difficult to say anything about the role of SR in epidemiology of FMD based on this study. Line 824-25. You found high Seroprevalence does not confirm that they transmit and maintain the disease. So this conclusion cannot be warranted based on your findings. Line 826. “Cross contamination” has to be replaced with cross transmission Line 827. ‘This outlays’? Line 829 ..”post”.. ?? Figures The legends and labels of all figures (fig.1,2,3) are not visible Reviewer #2: This study aims to determine the seroprevalence of FMD in small ruminants and determine the risk factors associated. This is an original, highly useful study that may be utilised to further understand the epidemiology of FMD transmission in Kenya. The manuscript is very thorough, however is much too long, particularly the introduction. The whole manuscript needs to be made more concise, as there is a lot of repetition throughout, between sections, between the text and figures, and between figures. Some tables could be merged, with some columns removed – for example tables 3 and S4. The current layout makes it more confusing to the reader than it needs to be – as this is a simple study approach with good results. However, the message seems to get lost in the length of the manuscript. For the introduction, only information relevant to the study should be included, for example detail on molecular tests and differential diagnosis is not required – potentially only mentioned. Much of the information is or could be included in the discussion if it is necessary. Additionally, please ensure that you include references where appropriate, there are multiple sections where there are not enough references. The methods section is very repetitive, particularly regarding the description of the number of counties, and the data analysis section could be much more concise. Additionally, the ELISA method does not need to be described in such detail as it is a commonly used test. In the results section, please ensure that your subheadings accurately reflect what is included within them and avoid repetition between tables and the text. Additionally, are chi-squared test required if regression has been done? Or can this be more concisely displayed e.g. all in one table? At the moment it is very difficult to flip between all of the tables and the lengthy text to work out the results. Additionally, I would like to see in the descriptive analysis the number of animals that were vaccinated for FMD and that had clinical signs (even if it was 0). This is very important information when investigating seroprevalence. Particularly when the vaccines administered in Kenya are often not of high quality and may induce NSP antibodies – this should also be mentioned in the discussion. Additionally, please be careful with capitalised words that do not need to be, for example ‘county’ and directions (east/west etc.) Consequently I recommend major revisions to this manuscript to make it more 'reader friendly'. ********** 6. 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: No Reviewer #2: Yes: Bryony Armson [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment 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. Registration is free. 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 PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. |
| Revision 1 |
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PONE-D-20-15166R1 Epidemiological study on foot-and-mouth disease in small ruminants: sero-prevalence and risk factor assessment in Kenya PLOS ONE Dear Dr. Kairu-Wanyoike, 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. ============================== Overall revision was satisfactory. Both the reviewers have identified several minor points that we request you to consider for the revision. ============================== Please submit your revised manuscript by May 22 2021 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:
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. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols. We look forward to receiving your revised manuscript. Kind regards, Jagadeesh Bayry, DVM, PhD, HDR Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. [Note: HTML markup is below. Please do not edit.] 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: (No Response) ********** 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: Yes Reviewer #2: Yes ********** 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: Comments to authors General comments. The manuscript has been considerably improved by the authors following the first round of comments. However, there are some issues remaining to be resolved. They are detailed below. Note. The line numbers were not working in many cases. This made difficult to trace the corrections and has to be corrected in the next versions. Introduction Line 134. What have found to be the role of small ruminant in the epidemiology of FMD? Are they carrier transmitter, spill over hosts, primary host which can maintain the disease by themselves irrespective the presence of cattle or what? I don’t think the scope of the work can lead to these types of conclusions. Material and methods Line 184. A herd….. Line 187. Instead of the software, provide reference for methodology of the sample size determination. Moreover, the website. http://www.promesa.co.nzl seems not working. check it. Line 188. ‘expected between herd prevalence 30%” what does it mean and how is the 30% determined? Line 190. Where did your get the intracluster correlation is 0.2? Line 193. “Prevalence in a herd is 20%”. Give reference from where did you get this? Generally, as which sample size formula is used is not mentioned, it is difficult to understand how sample size was determined. Line 198 . remove” Because it was one village per sub-location and one herd per village, it is appropriate to use the terms interchangeably” as it is confusing which terms it refers, and it also adds no clarity. Line 224-227. multistage sampling; sublocation, village, herd and then individual animals. Compare this with your description in line 181-183. Line 308. (Pearson?) correlation coefficient of 0.3 threshold for collinearity is highly conservative. Are there any references for this? Multicollinearity would have been more appropriate than simple collinearity. Results Line 334. Herd was defined better in M& M and not needed here. Line 344. design effect for 2 may not be high for FMD as it id highly transmitted within a herd and could result high clustering effect. Line 403. “None of the herds surveyed had animals that showed FMD signs” . this should be qualified as at the time of sampling. Line 447. What are you doing in the above two tables? were you not assessing association of risk factors for SR FMD? When you say FMD seropositivity was higher in adult than young, don’t you mean age is a risk factor?! So the above analysis a univariable (crude) risk factor analysis and should come under risk factors analysis title. Actually, I don’t see its importance as far as you do the multivariable analysis as in table 5. After all the definitive test for risk factor is the multivariable test. This has been commented in the previous version. Line 489. Table 5. This is the final model. Then why was the non-significant factors such as Brought in SR, SR breeding method, elevation included in the final model. In the methodology it was mentioned backward fitting (selection?) was used. If that is the case, in backward selection at each iteration the non-significant variables are removed until only significant factors and confounding factors remain in the final model. Line 513. The interpretation for interaction is not clear. After the doing the interaction I would expect results such as: maleness and adultness interact positively and increased risk of FMD more than either of maleness or adultness alone. Discussion Line 534. Across the categories Line 583-684. Any evidence about subclinical infection SR to conclude this? Conclusion Line 600. What is this role? Line 600 -604 your result could not give any clue about potential transmission of FMD between cattle and sheep let alone sheep as reservoir of infection for cattle. Is it not possible SR are getting infection from cattle? It is known that cattle are more susceptible to FMD and are often the maintenance hosts for FMD viruses except SAT viruses where African buffalo are involved. Cattle tend to be carrier longer and only short period of carrier was reported for SR. This comment has been given in previous version as well but not has not been corrected. So should be corrected or need convincing explanation. Reviewer #2: The authors have done a good job in working on the previous reviewer’s comments. Unfortunately, it seems some of my specific comments from review round 1 were not sent forward to the authors and therefore some that have not already addressed are repeated here again below. Although the manuscript has been shortened, I still think there is a requirement to further make the introduction and results more concise, which will make the study more pleasurable to read, as the results are good. I think there are options for tables to be combined and the number of columns reduced so that the important results do not get lost (see specific comments below). Additionally, from what I can see there is no description as to what S2 file 1 represents and therefore I think it should be removed. Specific comments Abstract Line 31-32 – No need to capitalise ‘non-structural proteins’. And remove the second full stop after ‘kit’. Line 37 – Please provide the p number – not just say that it is was less than 0.05. Also, I think just the p value is enough, no need to include X2 value). However, I think there is no need to include this sentence (‘Sero-positivity was significantly……..p<0.05)’, as you have stated below that the sedentary production zone was negatively associated with seropositivity (line 40-41). Introduction Needs shortening further and moving a few things around to make more concise. A focus on Kenya and small ruminants is recommended. Line 72 – I do not think there is a need for Table 1. Or if so it should be included in the supplementary files. I think a short sentence about FMD prevalence on other East African countries would be enough here. Lines 66-70 – Suggest removing this short paragraph, and instead mentioning seroprevalence studies of FMD in small ruminants in other East African countries. Lines 75-108 – suggest reducing this further to make the introduction more concise. I think the most important thing to mention is FMD in small ruminants. (serotypes in Kenya are already mentioned below so no need to mention here?) Lines 109-119 – Suggest removing this paragraph. Lines 124 – 127 – Suggest removing these two sentences (‘Vaccination programmes…….maternal immunity’). Lines 135 – 137 – suggest removing this sentence (‘This is because…..borders’). Methods Lines 151-158 – I think that this paragraph can be removed? Line 161 – Add a full stop after ‘country’. Figure 1 – I’m not sure if it is just the version that is attached to this PDF, but please ensure Figure 1 is clear, as the version I can see is blurred. Lines 183 – 184 – Suggest removing these sentences (‘The total sample……strata’). Also suggest using the term zone instead of strata going forward. Line 184 – please do not capitalise the word ‘herd’. Line 188-189 – please state why a 30% expected between herd prevalence was used, and in line 193, why an expected prevalence of FMD in the herd of 20% was used. What information was this based on? Lines 214-216 – suggest removing these two first sentences as this information has already been described previously. Line 218 – change to ‘these WERE used…’ Line 279 – 280 – Were two different ELISA tests performed or is the ‘3ABC blocking enzyme-linked immunosorbent assay’ the same as the ‘3 ABC- ELISA ID Screen®FMD NSP Competition kit’. I assume they are the same, but I think it is confusing here. Maybe it is best to say in line 275 that ‘Individual animal serum samples were analysed……’ and then remove the sentence in line 279-280 (‘At individual level……assay’). Line 287 – I do not think S2 file should be included – it is not very self-explanatory, and all of the data are in the other supplementary files. Line 295 – What does this refer to? ‘--“Bunny-Wunnies Freak Out”’? Please remove. Results Line 340 – Please do not capitalise ‘counties’ Lines 341-345 – Suggest moving this sentence and reasoning to the discussion. Suggest removing Table 2, as the important information is displayed in the other tables. Move to supplementary data if necessary to keep it. I am not sure what the column ‘sum’ refers to in Table 2. Is this table referring to the herd sizes that animals were sampled from, or the animals sampled? Lines 355-398 – This section needs to be made more concise – suggest reducing to one paragraph. If the Table is brought to the main article instead of supplementary, only a short summary of results is required. Lines 403-405 – Please improve the English language of this sentence. I’m not sure that confidence intervals are required for apparent sero-prevalence – only for true prevalence. Table 3 – remove variable code. Suggest to remove the ‘negative’ column. Suggest adding p value column for each variable in Table 3 for chi squared test. Then the reader can clearly see the results without hunting through the text. Table 4 – remove variable code. Suggest to remove the ‘negative’ column. Suggest adding p value column for each variable in Table 4 for chi-squared test. Then the reader can clearly see the results without hunting through the text. Can Tables 3 and 4 be combined? Lines 403-474 – Remove ꭓ2 values from the text and only include p values. Also this section needs to be made more concise. Including the p values for the chi-squared tests in Tables 3 and 4 would mean less description is required. Line 479 – Do ‘all the potential risk factors’ mean all of those in Tables 3 and 4? Please be clear. Table 5 – Combine with Table 6? There are too many unnecessary columns. Suggest removing the columns B, Se/S.E. and Z ratio. Discussion Line 534 – ‘categories’ is spelled incorrectly. Line 541 – change ‘FMD outbreak peaks is…’ to ‘FMD outbreaks are associated…’. Line 545 – Although foot and mouth disease is spread by contact, I would recommend changing this sentence as other methods of transmission are also common e.g. fomites/aerosol. It is more likely that as herd are closer together there are more chances for the virus to spread? Line 581 – ‘transmission’ is spelled incorrectly. Suggestion to include a discussion about the limitation of the study that testing was not done for circulating virus (e.g. virus isolation/PCR), and therefore it is unknown when these animals became infected. Indeed, further investigations (potentially using the same samples) could be done and also to identify the serotypes that the SR were infected with using serotype specific ELISAs. Line 606 – Remove double word ‘cross’. ********** 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: No Reviewer #2: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment 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. Registration is free. 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| Revision 2 |
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Epidemiological study on foot-and-mouth disease in small ruminants: sero-prevalence and risk factor assessment in Kenya PONE-D-20-15166R2 Dear Dr. Kairu-Wanyoike, 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. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Jagadeesh Bayry, DVM, PhD, HDR Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: |
| Formally Accepted |
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PONE-D-20-15166R2 Epidemiological study on foot-and-mouth disease in small ruminants: sero-prevalence and risk factor assessment in Kenya Dear Dr. Kairu-Wanyoike: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Jagadeesh Bayry Academic Editor PLOS ONE |
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