Ebola won't spread to many people in the United States unless the virus mutates, a top federal health official told Congress on Thursday as fallout continued from the infection of a second Dallas nurse who had treated a now-dead Ebola patient and then flew on a commercial airline.
"There is zero doubt in my mind unless there's a mutation there will not be a large-scale outbreak in the U.S.," said Dr. Thomas Frieden, director of the federal Centers for Disease Control.
Frieden's comments came as both he and the Obama administration resisted renewed calls for a travel ban for three West African countries that are currently dealing with the worst Ebola outbreak since the virus was discovered in the mid-1970s.
Hours later, the CDC said it will now track passengers who were on a plane with Ebola-infected nurse Amber Joy Vinson took from Dallas to Ohio last Friday, in addition to the passengers it was already tracking from a flight she took back to Dallas on Monday.
"We can't rule out that she might have had the start of her illness on Friday," Dr. Chris Braden of the CDC said at a briefing, as he cited new information developed by investigators tracing all of Vinson's contacts. Vinson would have become contagious after developing symptoms.
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The U.S. Health and Human Services Department on Thursday said it is providing $5.8 million in funding to accelerate development of a third Ebola vaccine, by Profectus BioSciences Inc. Two other potential vaccines, one produced by GlaxoSmithKline, the other by Canada's public health agency and NewLink Genetics, are currently undergoing clinical trials.
"We are pushing hard to advance the development of multiple products as quickly as possible for clinical evaluation and future use in preventing or treating this terrible disease," said Robin Robinson, director of HHS's Biomedical Advanced Research and Development Authority.
There is no vaccine currently approved for Ebola, nor are there any approved treatments for the virus. However, at least three experimental drugs have been used on an emergency basis for several Ebola patients during the current outbreak, although it is not clear if the drugs worked.