In both previous Ebola outbreaks in Africa and the current Ebola outbreak caused by the Bundibugyo virus in the Democratic Republic of the Congo, neighboring countries have been the most affected when it comes to cross-border spread. Van Zandvoort et al. note that decision-makers outside Africa may be considering border and travel policies to cut off international transmission routes. We identified and analyzed all known Ebola cases outside Africa and assessed the risk of undetected cases. ortho ebola virus It’s about considering the possibility of transmission outside Africa and weighing it against possible border and travel policies.
The authors searched scientific articles, public health bulletins, and news reports for all laboratory-confirmed Ebola cases with onset outside Africa from 1976 to the present, including cases of infection outside Africa with Bundibugyo, Ebola, or Sudan virus, and cases with exposure in Africa and subsequent travel outside the continent, or cases with exposure outside Africa.
Two Types of Exported Cases: Medical Evacuation and Potential Cases
The search identified a total of 28 Ebola cases confirmed outside Africa from 1976 to May 2026, of which 25 were primary imported cases and 3 were secondary cases acquired from another patient in the United States or Europe.
The analysis distinguishes between two main types of exported cases. On the one hand, the analysis also included people who were medically evacuated after a confirmed infection, meaning those who were safely transported by air ambulance for treatment outside Africa. Latent cases, on the other hand, were defined as people who developed symptoms during or after returning from an outbreak area on a commercial flight. The first group is a known risk and strict measures may reduce the risk of infection, while the second group requires diagnosis and isolation.
Most of the confirmed cases (27) occurred during the 2014-2016 Ebola virus outbreak in West Africa, and one occurred during the ongoing 2026 Bundibugyo virus outbreak. The authors detected four latent cases, all of which were exported abroad during the 2014-2016 Ebola outbreak. These four cases were among 300,000 travelers tested at the time. However, all four were asymptomatic (and therefore undetectable) at the time of departure and immigration. Three were medical workers who returned to fight the epidemic, and one helped a pregnant person receive medical assistance.
Overall risk of exporting is low
Based on these data, van Zandvoort et al. estimated that the approximate overall risk since 2000 was 0.17 Ebola cases outside Africa for every 1,000 cases reported in Africa (excluding medical evacuation cases). The authors concluded: “Overall, our results suggest that the risk of case spillage is low and could be substantially mitigated by infection control measures at the source and among outbreak response workers, as well as enhanced travel screening and monitoring of returning response workers, as recommended in the WHO border and travel guidance for current outbreaks.”
Therefore, the authors have the following views:Exit screening in countries affected by the epidemic aims to reduce the importation of infected people to other countries, which is a shared international responsibility. This may be best supported by strengthening local capacity for such screening.. ”
sauce:
European Center for Disease Prevention and Control (ECDC)
Reference magazines:
The risk of global spread of Ebola virus is low: Epidemiology of Ebola cases outside Africa from 1976 to May 2026. euro monitoring. DOI: 10.2807/1560-7917.ES.2026.31.24.2600508.
