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By Julie Steenhuysen
CHICAGO, July 31 The U.S. Centers for Disease Control and Prevention on Thursday issued a travel advisory against non-essential travel to Guinea, Liberia and Sierra Leone to curb the spread of the Ebola outbreak in West Africa that has claimed more than 700 lives.
CDC Director Dr. Thomas Frieden said his agency will send an additional 50 disease experts to assist with efforts to contain the highly deadly virus, in what he called "the largest, most complex outbreak that we know of in history."
Sierra Leone has declared a state of emergency and called in troops to quarantine Ebola victims, joining neighboring Liberia in imposing controls, as the death toll from the outbreak of the virus in West Africa hit 729.
In a conference call with reporters, Frieden said the United States is joining the World Health Organization and others in escalating efforts to fight Ebola. He estimated that it could take at least three to six months to get the outbreak under control.
The advisory against non-essential travel to the three affected countries aims to prevent visitors from being exposed to Ebola in local health facilities should they need medical attention for other ailments, Frieden said.
He also said airlines will continue to fly into the affected region, which will help maintain essential functions in the region.
Earlier on Thursday, the World Health Organization said it was launching a $100 million response plan to combat Ebola in West Africa, but is not recommending travel restrictions or border closures due, saying there would be a low risk to other passengers if an infected person flew.
CDC is also helping with screening and education efforts in West Africa to prevent sick travelers from getting on planes.
If they do, Frieden said the agency has protocols in place to protect against further spread of disease, including notification to CDC of ill passengers on a plane before arrival, investigation of ill travelers, and, if necessary, quarantine.
Ebola poses "little risk to the U.S. population," Frieden said on the call.
Earlier this week, CDC issued a health alert notice, reminding U.S. healthcare workers of the importance of taking steps to prevent the spread of the virus, how to test and isolate suspected patients and how they can protect themselves from infection.
There are no vaccines or effective treatments for Ebola, Frieden noted, adding that containing the outbreak will require the "meticulous work" of quarantining the sick and those who have been in contact with them. (Reporting by Julie Steenhuysen; Editing by James Dalgleish and G Crosse)