The World Health Organization says it won’t recommend screening passengers traveling from Guinea, Liberia or Sierra Leone for Ebola.

Some say it’s because it’s too costly.

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Above, watch a panel debate this on “Bulls and Bears.” Read more from USA Today below.

Sick people are urged not to travel. Because Ebola's incubation period is two to 21 days and early symptoms aren't specific, using thermal scanners to detect fevers is costly, unlikely to detect anyone infected with Ebola "and is not encouraged," according to the WHO.

Health officials are monitoring the worst Ebola outbreak in history in consultation with the International Air Transport Association, which represents 240 airlines worldwide, and the International Civil Aviation Organization, a branch of the United Nations that sets policies.

"Discussions are currently being held regarding travel and trade," said Leticia Linn, a WHO spokeswoman, and an update "will likely come next week."

The Ebola outbreak has killed more than 700 people in West Africa and infected more than 1,300, according to the WHO.

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