If passengers weren't screened before they boarded airplanes in the Ebola-affected countries of Guinea, Liberia and Sierra Leone, three people infected with Ebola would leave on international flights from any of those West African nations every month, a new analysis predicts.
Departure and arrival screenings
The three countries are those hit hardest by the current Ebola outbreak. Screening is currently in place at international airports in cities there, and the study results highlight the need to maintain it, according to a team led by Dr. Kamran Khan, of St. Michael's Hospital in Toronto.
In the study, the researchers analysed airline flight schedules and passenger destinations, along with Ebola infection data, to determine how effective air travel restrictions and airport departure and arrival screenings are in helping control the spread of Ebola.
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In the current situation, about three people infected with Ebola would board international flights every month from Guinea, Liberia and/or Sierra Leone if there was no screening of passengers before they departed those countries, Khan's team reported in The Lancet.
"The risk of international spread could increase significantly if the outbreak in West Africa persists and grows. Risks to the global community would further increase if Ebola virus were to spread to and within other countries with weak public health systems," Khan said in a journal news release.
It's far more efficient and less disruptive to screen airline passengers for Ebola when they leave West Africa than to screen them when they arrive at airports around the world, the researchers added.
"Exit screening at the three international airports [Conakry, Monrovia and Freetown] in Guinea, Liberia and Sierra Leone should allow all travellers at highest risk of exposure to Ebola to be assessed with greater efficiency compared with entry screening the same passengers as they arrive in cities around the world," Khan said. "However, this will require international support to effectively implement and maintain."
The researchers also noted that more than 60 percent of people flying out of Guinea, Liberia and Sierra Leone this year are expected to have final destinations in less-developed nations.
"Given that these countries have limited medical and public health resources, they may have difficulty quickly identifying and effectively responding to imported Ebola cases," Khan said.
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However, even though screening airline passengers before they leave the three West African countries is useful, it's only one measure and does have downsides, he added.
"The best approach to minimise risks to the global community is to control the epidemic at its source," Khan said. "While screening travellers arriving at airports outside of West Africa may offer a sense of security, this would have at best marginal benefits, and could draw valuable resources away from more effective public health interventions."
Some in the United States have called for a ban on air travel from Ebola-affected countries. But Khan believes that more "excessive constraints on air travel could have severe economic consequences that could destabilise the region and possibly disrupt critical supplies of essential health and humanitarian services."
The Ebola outbreak in West Africa has killed nearly 4,500 people out of an estimated 9,000 reported cases, according to the World Health Organization.
The Ebola outbreak so far
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