Tracing COVID-19 Trails in Wastewater: A Systematic Review of SARS-CoV-2 Surveillance with Viral Variants
, Sangeet Adhikari 2, Shuxin Zhang 3, Tamunobelema B. Solomon 4, Anssi Lipponen 1, Md. Aminul Islam 5,6, Ocean Thakali 7, Sarawut Sangkham 8, Mohamed N. F. Shaheen 9, Guangming Jiang 3,10, Eiji Haramoto 11, Payal Mazumder 12, Bikash Malla 11, Manish Kumar 12,13, Tarja Pitkänen 1,14 and Samendra P. Sherchan 4,15,*,†Round 1
Reviewer 1 Report
This manuscript describes “Tracing COVID-19 Trails in Wastewater: a systematic review of 2SARS-CoV-2 Surveillance with Viral Variants”.
1. Before the introduction section, add the content list of this manuscript. This may provide the guideline of readers. Check with the journal guideline if the content lists can be added.
2. The section 4.4 provides various analytical methods to detect the COVID-19. Add the comparison table for those methods including benefits and limits.
3. Add the methods or previous trials how to predict the number of potential COVID-19 with wastewater surveillance data (Molecular methods). The ultimate goal of the wastewater-based epidemiology should be the prediction of the COVID-19 number in certain area. Are there any reports in previous between tracking COVID-19 Trail in wastewater and prediction of COVID-19 population?
Author Response
Dear Sir/Madam,
Thank you so much for your constructive comments. We have addressed and attached them.
Sincerely with
ananda
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments:
0. Major revision. 1. The novelty of this study should be inserted in the text clearly. 2. The advantages and disadvantages of this study should be investigated. 3. The mechanism of removal of COVID-19 from wastewater should be presented in detail. 4. The stability of COVID-19 in wastewater should be studied.Author Response
Dear Sir/Madam,
Thank you so much for your constructive comments. We have addressed and attached them.
Sincerely with
ananda
Author Response File: Author Response.pdf
Reviewer 3 Report
General comments
The systematic review presented is interesting and timely because it takes stock of the methods used and the results of the monitoring of SARS-COV-2 variants in wastewater.
Specific comments
A check of the dates reported in figure 1, in the manuscript text and in table 1 is required because there are some discrepancies:
· it is suggested to indicate in the caption of Figure 1 that the date refers to when the variant was declared VOC by the WHO
· Line 124 “The Alpha variant was first isolated in the United Kingdom in November 2020” In table 1 is reported the first detection in September 2020
The Authors should review the following sentences because reading the paragraph they could appear in contrast:
· Lines 106-107 SARS-CoV-2 has a proofreading capability enabling it to stabilize its 29.9-kilobases (kb) long genome [30].
· Lines 112-114 SARS-112 CoV-2 has a similar mutation mechanism to other ssRNA viruses that lack proofreading capability, giving rise to new variants [25].
Line 127 “and globally in at least 184 countries (Table 1).” Check the number because in Table 1 are reported 189 countries
To better characterize the impact of different variants on epidemic peaks in the specific paragraphs describing the different variants the Authors should report data on infectivity (ex. R0) and lethality of the reported variants
Add in the cited references in the caption of Table 1 the WHO, in addition to 1 and 37 referred to CDC and ECDC
If feasible, authors could update data on the epidemic situation and the classification of variants in January 2023
Author should clarify the note at the end of the Table 1
To improve the text in the paragraph 4.4 “Analytical methods to detect variants” the authors could add a graph or a table with an indication of the use of the various methods (%) in the different studies.
Line 389 add in the text the meaning of the acronym SNPs
The articles analysed to write the review reported in the table in the supplementary material should be reported in the reference list of the main text. For example, authors could quote articles in the text (ex. 1-80) and then report them in the references. Refer to the link https://www.mdpi.com/authors/layout#_bookmark83 Di seguito le indicazioni MDPI
“Citations and References in supplementary files are permitted provided that they also appear in the reference list of the main text; if references in individual supplementary files are included in the main text, all of the references should have a citation in the “Supplementary Materials” section (e.g., “References [x,x] are cited in the Supplementary Materials”) or in main text.”
Author Response
Dear Sir/Madam,
Thank you so much for your constructive comments. We have addressed and attached them.
Sincerely with
ananda
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Accept
