A medical missionary being treated for Ebola virus infection in Nebraska is almost better, his doctors said Wednesday. "Based on what we're seeing know, we expect him to make a full recovery," said Dr. Angela Hewlett, associate medical director of the Biocontainment Unit at The Nebraska Medical Center. "However, we are still somewhat cautious because of the severity and unknown factors of this disease. We know from experience how other patients look as their condition improves, but since we have so little experience treating patients with Ebola, that tempers our optimism a little bit."

"He looks great in person," said Dr. Phil Smith, medical director of the unit. To be cleared for discharge, Sacra will have to test negative for Ebola twice, with tests given 24 hours apart. Medical workers are at high risk of infection from Ebola, which has sickened at least 5,000 people and killed half of them. Medecins Sans Frontieres (MSF or Doctors Without Borders) says one of its medical workers has been infected and evacuated to France. An American doctor working for the World Health Organization is being treated at Emory University Hospital.

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— Maggie Fox