A person who moved from Liberia to Dallas a week ago has tested positive for Ebola, becoming the first person diagnosed in the U.S. with the potentially deadly virus, the City of Dallas confirmed Tuesday.
The patient was hospitalized at Texas Health Presbyterian Hospital on Sunday after falling ill four days earlier, on Sept. 24.
The Dallas Fire-Rescue ambulance crew who transported the infected man to the hospital is being quarantined and monitored for Ebola symptoms, Dallas Mayor Mike Rawlings told NBC 5, and the ambulance used to transport the man has been pulled from service.
The number of people in the DFR crew being monitored is not known.
After receiving the Ebola diagnosis, the city activated its Emergency Operations Center and is on Level 2: High Readiness.
The patient showed no symptoms of the virus when he left Liberia on Sept. 19 and arrived in the U.S. a day later, according to CDC Director Dr. Thomas Frieden.
There was no risk to any fellow airline passengers because the man had no symptoms when he was traveling, Frieden said.
The patient didn't begin developing symptoms of the virus until Sept. 24 and sought care on Friday. He was hospitalized the following Sunday and placed in isolation.
According to the City of Dallas, the patient had moved to Dallas a week ago.
Earlier, officials said the patient came to Dallas to visit family. It is unclear what the unidentified man's nationality is.
At this time, state and federal health officials said there are no other confirmed or suspected cases of Ebola virus in the state.
The CDC is working to identify and monitor all the people who may have come into contact with the patient while he was infectious. Those people, like the DFR fire crew, will be monitored for 21 days for Ebola symptoms.
Should symptoms develop, those patients too will be isolated, and investigators will then determine who they came into contact with and monitor those people for symptoms.
"I have no doubt that we will control this importation or this case of the Ebola so that it does not spread widely in this country. It is certainly possible that someone who had contact with this individual, a family member, or other individual, could develop Ebola in the coming weeks, but there is no doubt in my mind that we will stop it here," said Frieden.
The Ebola diagnosis was confirmed Tuesday after specimens were sent from Presbyterian Hospital to the Texas public health laboratory in Austin, the Texas Department of State Health Services said Tuesday.
The Austin lab, which was certified last month to test for Ebola, confirmed the result and sent the sample to the CDC in Atlanta, which confirmed it.
President Barack Obama was briefed about the diagnosis in a call from Frieden, the White House said.
Word of the infection alarmed the local Liberian community.
"People have been calling, trying to find out if anybody knows the family," said Stanley Gaye, president of the Liberian Community Association of Dallas-Fort Worth. "We've been telling people to try to stay away from social gatherings."
Dallas Patient the Fifth Ebola Patient Treated in U.S. This Year
The patient is the fifth person treated for Ebola in the country this year after missionaries Dr. Kent Brantly, Nancy Writebol and Dr. Rick Sacra all contracted the virus while working in West Africa.
The Dallas patient will continue to be treated at Texas Health Presbyterian Hospital of Dallas, according to Dr. Edward Goodman, hospital epidemiologist at Presbyterian.
Both Brantly and Writebol have fully recovered, after they were given experimental drugs and were treated at Emory University Hospital in Atlanta in August.
Sacra was treated at the University of Nebraska Medical Center and was released Sept. 25. He had been working in Liberia on behalf of SIM.
The identity and condition of the fourth patient has not been released. It is believed that they are still being treated at Emory Hospital.
Writebol issued a statement Tuesday after learning of the new diagnosis in Dallas on Tuesday.
"We are sad for the family of the patient and pray for recovery to good health. It is a mercy that the best medical care is available. We also pray for the safety of the medical staff attending to the patient," she said.
How is Ebola Spread?
Ebola is a severe, often fatal disease spread through close, direct contact with blood or other bodily fluids of a living or dead person who had contracted Ebola. The virus is only contagious when symptoms are present, and it is not spread through the air, through food or water.
Symptoms for Ebola virus involve a fever, severe headache, muscle pain, weakness, diarrhea, vomiting, abdominal pain and unexplained hemorrhage. Symptoms appear anywhere from two to 21 days after exposure but the average is eight to 10 days.
If someone exposed to Ebola has not shown symptoms for 21 days they are not expected to develop Ebola.
According to the CDC, recovery from Ebola depends on the patient's immune response. People who recover from Ebola infection develop antibodies that last for about 10 years.
The CDC said the United States is well-equipped to manage and treat Ebola and that the chances of an outbreak like the one in West Africa is extremely low.
NBC 5's Ben Russell and Scott Gordon contributed to this report.
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