The first Ebola patient diagnosed in the United States took a turn for the worse on Saturday, slipping from serious to critical condition, as health officials reported fielding scores of possible cases around the country that proved to be false alarms.
Dr. Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention, said news of the Ebola patient in Dallas had alerted hospitals nationwide to check incoming patients for potential risks, particularly those who had recently traveled from the center of the outbreak in West Africa.
The CDC has identified nine people who had contact with the Dallas patient from Liberia, Thomas Eric Duncan, and therefore may have been exposed to the virus, and an additional 40 are being monitored as potential contacts. None have shown symptoms, Frieden said.
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Frieden also said U.S. health authorities have responded to inquiries regarding more than 100 potential cases of Ebola since Duncan tested positive earlier this week, but no new infections have been identified.
On Saturday, CDC officials dressed in biohazard suits escorted two passengers off a United Airlines jet that landed at Newark Liberty International Airport in New Jersey because they were believed to be from Liberia and exhibiting signs of illness during the flight.
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The CDC says a full evaluation of the man at a local hospital showed "no evidence or concern for Ebola" and he was discharged "feeling well."
State health officials say the man's symptoms were consistent with a minor, treatable illness.
Port Authority spokeswoman Erica Dumas says the man began throwing up during the flight. Authorities say the plane's crew and roughly 250 passengers stayed onboard while officials tended to him.