American magnate Donal Trump has sparked outrage after he publicly said doctors who are treating Ebola patients in Africa "must suffer consequences".
Trump has been speaking about Ebola on Twitter since last weekend, when he slammed US leaders as "incompetent" for repatriating Americans who contract the virus while in Africa.
In one of his most inflammatory tweets, Trump said: "The U.S. cannot allow EBOLA infected people back. People that go to far away places to help out are great – but must suffer the consequences!"
He added: "They knew the risk when they went to Africa. They choose it freely."
Trump's tweets come as Dr Kent Brantly, one of two American aid workers infected with Ebola in Liberia, arrived back in the US. His assistant, Nancy Writebol, is expected to fly back later this week.
Dozens of people have liked and retweeted Trump's posts. However, others were outraged.
Ebola, for which no cure has been found yet, has killed at least 700 people in Liberia, Sierra Leone and Guinea since January. Another 1,200 are believed to have been infected.
Fears that the illness could spread worldwide were sparked after a passenger flying from Liberia to Nigeria died in a hospital in Lagos last July.
Some warned Ebola could also increase possibilities of terrorism worldwide.
According to Peter Walsh, a biological anthropologist from Cambridge University, there is a "serious risk that a group manages to harness the virus as a powder, then explodes it in a bomb in a highly populated public area. It could cause a large number of horrific deaths".