Mount Sinai Health System CEO Dr. Kenneth Davis told CNBC on Wednesday that a man with Ebola-like symptoms being treated at his New York City facility is "extremely unlikely" to have the deadly virus.
The patient, who recently traveled to West Africa, is stable and improving, Davis said in a "Squawk Box" interview, adding the hospital is waiting to hear back from the Centers for Disease Control and Prevention on tests later Wednesday or Thursday.
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He said the man was put into isolation "within seven minutes" of acknowledgement that his symptoms could be Ebola.
Many other diseases such as typhoid fever, malaria, or a gastrointestinal virus can present with the symptoms of high fever, nausea, vomiting and diarrhea like Ebola, Davis explained—saying those illnesses are more likely to be the cause of this patient's sickness.
"What is important to keep in mind for all the people who are anxious is this is a very hard disease to contract," the Mount Sinai CEO said. "You only get this disease by being in contact with bodily fluids and having those fluids enter your body—usually through a cut."
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He said Ebola should not be confused with illnesses such as the flu, "where it can be aerosolized—you breath it, you touch it and you get it."
Two Americans infected with Ebola are being treated at Emory University Hospital in Atlanta. "There is this report from Atlanta that this mixture of antibodies had a remarkable effect [on] a doctor who had been exposed," Davis said.
"The scientists who developed this treatment are from the United States," he said. "The treatment is experimental. It was obviously given as a last resort. Generally experimental treatments that haven't even been tried in humans go through much more testing before they are given."
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In Nigeria, a nurse there has died of Ebola. The country said it has five additional confirmed cases of the disease.
All six people had direct contact with a Liberian-American man who flew into Lagos last month after contracting the virus. He died of Ebola five days later.
Elsewhere, Saudi Arabia's Health Ministry says a man who was being tested for the Ebola virus and was in critical condition in an isolation ward has died.
The Health Ministry says the Saudi man died Wednesday morning in a hospital in Jiddah. He was hospitalized after showing symptoms of a viral hemorrhagic fever following a recent trip to Sierra Leone, where there has been an outbreak of Ebola.
—By CNBC's Matthew J. Belvedere. Wire services contributed to this report.