Dataset Information

Transmission of SARS-CoV-2 associated with aircraft travel: A systematic review.

ABSTRACT: Rationale for the review: Air travel may be associated with viruses spread via infected passengers and potentially through in-flight transmission. Given the novelty of the SARS-CoV-2 virus, transmission associated with air travel is based on transmission dynamics of other respiratory viruses. Our objective was to provide a rapid summary and evaluation of relevant data on SARS-CoV-2 transmission aboard aircraft, report policy implications, and highlight research gaps requiring urgent attention.

Methods

We searched four electronic databases (1 February 2020 to 27 January 2021) and included studies on SARS-CoV-2 transmission aboard aircraft. We assessed study quality based on five criteria and reported important findings.

Key findings

We included 18 studies on in-flight SARS-CoV-2 transmission (130 unique flights) and two studies on wastewater from aircraft. The quality of evidence from most published studies was low. Two wastewater studies reported PCR-positive samples with high Cycle threshold values (33-39). Index case definition was heterogeneous across studies. The proportion of contacts traced ranged from 0.68% to 100%. Authors traced 2800/19729 passengers, 140/180 crew members, and 8/8 medical staff. Altogether, 273 index cases were reported, with 64 secondary cases. Three studies, each investigating one flight, reported no secondary cases. Secondary attack rate among studies following up > 80% of passengers and crew (including data on ten flights) varied between 0-8.2%. The studies reported on the possibility of SARS-CoV-2 transmission from asymptomatic, pre-symptomatic, and symptomatic individuals. Two studies performed viral cultures with ten positive results. Genomic sequencing and phylogenetic analysis were performed in individuals from four flights.

Conclusion

Current evidence suggests SARS-CoV-2 can be transmitted during aircraft travel, but published data do not permit any conclusive assessment of likelihood and extent. The variation in design and methodology restricts the comparison of findings across studies. Standardized guidelines for conducting and reporting future studies of transmission on aircraft should be developed.

SUBMITTER: Rosca EC

PROVIDER: S-EPMC8499932 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundModes of transmission of SARS-CoV-2 are of key public health importance. SARS-CoV-2 has been detected in the feces of some COVID-19 patients, suggesting the possibility that the virus could, in addition to droplet and fomite transmission, be transmitted via the orofecal route.MethodsThis review is part of an Open Evidence Review on Transmission Dynamics of COVID-19. We conduct ongoing searches using WHO COVID-19 Database, LitCovid, medRxiv, and Google Scholar; assess study quality based on five criteria and report important findings. Where necessary, authors are contacted for further details on the content of their articles.ResultsWe include searches up until 20 December 2020. We included 110 relevant studies: 76 primary observational studies or reports, and 35 reviews (one cohort study also included a review) examining the potential role of orofecal transmission of SARS-CoV-2. Of the observational studies, 37 were done in China. A total of 48 studies (n=9,081 patients) reported single cases, case series or cohort data on individuals with COVID-19 diagnosis or their contacts and 46 (96%) detected binary RT-PCR with 535 out of 1358 samples positive for SARS-CoV-2 (average 39.4%). The results suggest a long duration of fecal shedding, often recorded after respiratory samples tested negative, and symptoms of gastrointestinal disease were reported in several studies. Twenty-nine studies reported finding SARS-CoV-2 RNA in wastewater, river water or toilet areas. Six studies attempted viral culture from COVID-19 patients' fecal samples: culture was successful in 3 of 6 studies, and one study demonstrated invasion of the virus into intestinal epithelial cells.ConclusionsVaried observational and mechanistic evidence suggests SARS-CoV-2 can infect and be shed from the gastrointestinal tract, including some data demonstrating viral culture in fecal samples. To fully assess these risks, quantitative data on infectious virus in these settings and infectious dose are needed.