A Case Series and Systematic Review of the Literature of Travelers Who Flew on Commercial Aircraft while Infected With Viral Hemorrhagic Fevers, 2004–2023

Viral hemorrhagic fevers (VHFs), specifically those that spread from person to person, have high mortality rates ranging from 17% to 89%, and outbreaks are a cause for international concern. While instances of translocation of VHFs via air travel have been documented, there have been no reported cases of transmission during air travel. We aimed to synthesize available data on travelers who flew while infected with VHFs to assess the risk of transmission during air travel through a systematic review and case series. Eight scholarly databases were searched for studies published from January 2004 to December 2023, describing VHF-infected travelers on commercial flights and resultant contact investigations. We excluded studies that were not original research, did not describe VHFs, or did not have full-text availability. Studies were imported into Covidence, which facilitated abstract screening, full-text review, and data extraction. Additionally, the Centers for Disease Control and Prevention Port Health Activity Reporting System (PHARS) database (previously the Quarantine Activity Reporting System, or QARS) was searched and reports of travelers who flew while infected with VHFs from 2005-2024 were extracted. Six studies and 4 PHARS reports were identified that described 7 travelers who flew while infected with VHFs. Two cases were symptomatic with wet symptoms (ie, diarrhea or vomiting) during travel, while the remaining 5 cases only had dry symptoms (ie, fever, myalgias), no symptoms, or unknown symptoms. None reported bleeding during travel. In 1 instance, transmission occurred after travel. While translocation of VHFs via commercial air travel has been documented, transmission during air travel has not. The small number of included cases limits generalizability of the findings.