Risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Transmission Among Air Passengers in China

  1. Maogui Hu
  2. Jinfeng Wang
  3. Hui Lin
  4. Corrine W Ruktanonchai
  5. Chengdong Xu
  6. Bin Meng
  7. Xin Zhang
  8. Alessandra Carioli
  9. Yuqing Feng
  10. Qian Yin
  11. Jessica R Floyd
  12. Nick W Ruktanonchai
  13. Zhongjie Li
  14. Weizhong Yang
  15. Andrew J Tatem
  16. Shengjie Lai

Reviewed by

Read the full article See related articles

Discuss this preprint

Start a discussion What are Sciety discussions?

Listed in

Log in to save this article

Abstract

Background

Modern transportation plays a key role in the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and new variants. However, little is known about the exact transmission risk of the virus on airplanes.

Methods

Using the itinerary and epidemiological data of coronavirus disease 2019 (COVID-19) cases and close contacts on domestic airplanes departing from Wuhan city in China before the lockdown on 23 January 2020, we estimated the upper and lower bounds of overall transmission risk of COVID-19 among travelers.

Results

In total, 175 index cases were identified among 5797 passengers on 177 airplanes. The upper and lower attack rates (ARs) of a seat were 0.60% (34/5622, 95% confidence interval [CI] .43–.84%) and 0.33% (18/5400, 95% CI .21–.53%), respectively. In the upper- and lower-bound risk estimates, each index case infected 0.19 (SD 0.45) and 0.10 (SD 0.32) cases, respectively. The seats immediately adjacent to the index cases had an AR of 9.2% (95% CI 5.7–14.4%), with a relative risk 27.8 (95% CI 14.4–53.7) compared to other seats in the upper limit estimation. The middle seat had the highest AR (0.7%, 95% CI .4%–1.2%). The upper-bound AR increased from 0.7% (95% CI 0.5%–1.0%) to 1.2% (95% CI .4–3.3%) when the co-travel time increased from 2.0 hours to 3.3 hours.

Conclusions

The ARs among travelers varied by seat distance from the index case and joint travel time, but the variation was not significant between the types of aircraft. The overall risk of SARS-CoV-2 transmission during domestic travel on planes was relatively low. These findings can improve our understanding of COVID-19 spread during travel and inform response efforts in the pandemic.

Article activity feed

  1. Version published to 10.1093/cid/ciab836
  2. ScreenIT

    SciScore for 10.1101/2020.12.21.20248383: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    NIH rigor criteria are not applicable to paper type.

    Table 2: Resources

    No key resources detected.

    Results from OddPub: Thank you for sharing your code and data.

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    Our study was subject to a variety of limitations. Firstly, due to the limitation of data availability, we only studied the risk of transmission within three rows (7 rows in total) in front of and behind the index case, and therefore did not consider possible transmission within a larger scope (including flight and train crews). However, previous studies showed that the seats within 3 rows to the index patients had the highest risk 52. Secondly, as with other similar studies, we cannot accurately determine when and where the infection occurred due to recall bias from passenger reported information32. Cases may have been infected in other places before or after travel, such as in terminals or railway stations, during the boarding process or even outside the airport and station. This might overestimate the risk of spreading COVID-19 on planes or trains, although we accounted for this by employing two scenarios to estimate the interval of risk. Thirdly, data on usage of personal protective equipment such as masks and goggles during the flight were not available to account for the impact of these interventions, although few passengers might use these measures before January 23, 2020 when the lockdown of Wuhan was in place. Fourthly, asymptomatic travellers might not be captured in this study, and transmission risk before the symptom onset might be overlooked. Lastly, the difference in the size and cabin layout of aircrafts and trains was not considered in the study, where first c...

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  3. Version published to 10.1101/2020.12.21.20248383 on medRxiv