New York man does not have Ebola
A man who recently visited West Africa and then was taken to hospital in New York City with a high fever and gastrointestinal symptoms does not have the Ebola virus.
Mount Sinai Hospital said the man tested negative for the deadly disease, which has erupted in West Africa.
The man was ill when he arrived at Mount Sinai Hospital on Monday.
The Centres for Disease Control and Prevention says six people in the US have been tested for Ebola since the outbreak was first reported and those results were negative.
Officials at US airports are watching travellers from Africa for flu-like symptoms that could be linked to Ebola.
The Ebola virus causes a fever that has killed more than 900 people since the outbreak erupted.
President Barack Obama says the Ebola virus is controllable with standard public health measures and the US is working with allies to send additional medical workers to West Africa.
The use of an experimental drug to treat American aid workers raises ethical questions about who should get any limited supplies of a drug that has never been tested in people.
Mr Obama says: "We've got to let the science guide us."
He says the outbreak has spread more rapidly than previous ones in part because affected countries' public health systems have been overwhelmed, but supporting efforts to rapidly identify and isolate patients can work.
The president was speaking at a news conference concluding a summit in Washington DC with African leaders.