Agent-Based Modeling of the Hajj Rituals with the Possible Spread of COVID-19

Round 1

Reviewer 1 Report

The article is interesting and well structured. The authors start from coherent and well stipulated assumptions, enabling a clear and well-justified analysis. The number of people with complete vaccination may change the data presented here, however, I understand that it is not yet possible to take this variable into account at this time.

The literature review could and should be more in-depth. This way the conclusions would be more consistent in terms of comparing case studies.

If this is done, the originality and the conclusions of this article may become more robust.

Author Response

Response to Reviewer 1

We would like to thank the reviewer for the careful reading and the constructive comments that helped us to improve the quality of our work.

Comment: The article is interesting and well structured. The authors start from coherent and well-stipulated assumptions, enabling a clear and well-justified analysis. The number of people with complete vaccination may change the data presented here, however, I understand that it is not yet possible to take this variable into account at this time.

The literature review could and should be more in-depth. This way the conclusions would be more consistent in terms of comparing case studies.

If this is done, the originality and the conclusions of this article may become more robust.

Response: We have expanded on the literature review in the introduction by providing previous examples of disease outbreaks in the Hajj and the response of decision-makers. The results & discussion and conclusion have also been reworked to be more coherent and robust. We hope that you find our changes successful in improving the overall quality of the paper.

Reviewer 2 Report

This was a very interesting paper to read. I like the fact that the authors decided to do computer simulations regarding the movement and proximity of pilgrims in different geographical contexts. I do have some suggestions for improvement.

1. There are some tense problems with this paper that can be improved with editing.

2. There were points in the paper where the explanation of the results of the models was confusing, especially for a non-quantitative person like myself. Maybe the authors can review these explanations to be clearer in their explanations.

3. Mangers of the Hajj have long had to deal with disease issues. There is a recently published chapter that looks at the history of diseases at pilgrimage events, such as the Hajj, which might add some context to this paper. The introduction could be bolstered by looking at the history of how Hajj managers have dealt with disease issues. More explanation regarding the Hajj would provide better context

Olsen, D. H. 2020. Disease and Health Risks at Mass Religious Gatherings. In K. A. Shinde and D. H. Olsen. Eds. Religious Tourism and the Environment. Wallingford, UK: CABI, 116-132.

4. Lines 63-64. This sentence does not make sense.

5. LIne 80: What efforts?

6. Lines 91-93. Repetitious.

7. Figure 9? Not Figure 1? Why the odd numbering of figures?

8. In looking at Figures 9 and 10 (1 and 2), it is difficult to judge the scale. How many people fit into these spaces? In Figures 11 and 12 (3 and 4), it would be helpful not just to see the one dot, but all the dots that represent people. This is not clear with the shading used.

9. What were the exact numbers inputted into the program and formulae used? How can someone replicate this study without this information?

10. Lines 153-164: How was the "agent" removed from the system? Did they exit the area, or did they just disappear? Unclear.

11. Line 194: What was the expected number of infected?

12. Lines 206-207: Repetitious.

13. Is it necessary to list the computer specs? If so, it is fine.

14. I found 3.1.4 difficult to follow. Rewrite this section?

15. Lines 315-217: Why were the control measures more effective at one sit versus the other? Explain why this might have been the case.

16. The conclusion seems rushed. While yes, this paper does give quantitative data for decision-makers, what are the recommendations the authors have for these decision-makers? Just presenting quantitative data is not enough.

Author Response

Response to Reviewer 2

We would like to thank the referee for the careful reading and the constructive comments that helped us to improve the quality of our work.

Comment: 1. There are some tense problems with this paper that can be improved with editing.

Response: The overall wording in the paper has been reviewed, and changes in some areas were made to fix this.

Comment: There were points in the paper where the explanation of the results of the models was confusing, especially for a non-quantitative person like myself. Maybe the authors can review these explanations to be clearer in their explanations.

Response: We appreciate your input on this matter and have improved the qualitative explanation of the results in the Results & Discussion section. We have included an additional analysis that we hope would provide a clear explanation of the qualitative trends observed by the control measures.

Comment: 3. Mangers of the Hajj have long had to deal with disease issues. There is a recently published chapter that looks at the history of diseases at pilgrimage events, such as the Hajj, which might add some context to this paper. The introduction could be bolstered by looking at the history of how Hajj managers have dealt with disease issues. More explanation regarding the Hajj would provide better context.

Olsen, D. H. 2020. Disease and Health Risks at Mass Religious Gatherings. In K. A. Shinde and D. H. Olsen. Eds. Religious Tourism and the Environment. Wallingford, UK: CABI, 116-132.

Response: Thank you for the feedback and for the reference. We have expanded the introduction to include more information on the history of outbreaks during the Hajj pilgrimage from the given reference and other references to add context to the paper.

Comment: 4. Lines 63-64. This sentence does not make sense.

Response: These lines have been reworked, and more context has been added for further clarification and examples.

Comment: 5. Line 80: What efforts?

Response: This line has been removed.

Comment: 6. Lines 91-93. Repetitious.

Response: These lines have been removed to avoid repetition from the ideas presented in the Introduction.

Comment: 7. Figure 9? Not Figure 1? Why the odd numbering of figures?

Response: The numbering on the figures has been fixed.

Comment: 8. In looking at Figures 9 and 10 (1 and 2), it is difficult to judge the scale. How many people fit into these spaces? In Figures 11 and 12 (3 and 4), it would be helpful not just to see the one dot, but all the dots that represent people. This is not clear with the shading used.

Response: Capacity information for Figures (1 and 2) has been added in the captions. Figures (3 and 4) have been changed as per the recommendations. These changes were aimed at better showing the flow of the crowd movement in the simulations.

Comment: 9. What were the exact numbers inputted into the program and formulae used? How can someone replicate this study without this information?

Response:

 Comment: 10. Lines 153-164: How was the "agent" removed from the system? Did they exit the area, or did they just disappear? Unclear.

Response: This was clarified in the text.

Comment: 11. Line 194: What was the expected number of infected?

Response: We refer to the definition of the “infection reproduction number” as the number that an active infected agent would be expected to infect. The formula for this calculation is provided in Equation 2.

Comment: 12. Lines 206-207: Repetitious.

Response: This has been fixed. The lines were restructured, and repetitions of words were removed.

Comment: 13. Is it necessary to list the computer specs? If so, it is fine.

Response: We have included the specs to address any issues with the reproducibility of the results.

Comment: 14. I found 3.1.4 difficult to follow. Rewrite this section?

Response: This section has been rewritten as per the recommendations.

Comment: 15. Lines 315-217: Why were the control measures more effective at one sit versus the other? Explain why this might have been the case.

Response: We have expanded on this point in the text to include the effect of the crowd dynamics in each ritual being the main driver behind this phenomenon.

Comment: 16. The conclusion seems rushed. While yes, this paper does give quantitative data for decision-makers, what are the recommendations the authors have for these decision-makers? Just presenting quantitative data is not enough.

Response: We have expanded on our recommendations for policymakers and worked on improving the overall conclusion to further support our arguments.