More people may have been exposed to the contagious man after he first sought treatment on September 25 because an apparent miscommunication among staff resulted in his release back into the community for several days, Texas hospital officials admitted.
Ebola is spread through close contact with the bodily fluids of an infected person, and can only be transmitted when a patient is showing symptoms like fever, aches, bleeding, vomiting or diarrhea.
The man -- the first person to be diagnosed with Ebola on US soil -- flew from Liberia, the hardest-hit nation in West Africa's deadly Ebola outbreak, and arrived in Texas September 20 to visit family. He fell ill on September 24.
He went to the hospital the next day but was sent home because the medical team "felt clinically it was a low-grade common viral disease," said Mark Lester, executive vice president of Texas Health Resources.
"He volunteered that he had traveled from Africa in response to the nurse operating the checklist and asking that question," Lester added.
"Regretfully, that information was not fully communicated throughout the full team."
A hospital statement issued later said his initial symptoms on September 25 were "low-grade fever and abdominal pain," and that "his condition did not warrant admission."
The patient is currently in serious but stable condition.
He came in contact with five schoolchildren before he returned via ambulance to the Texas Health Presbyterian Hospital Dallas on September 28, and was placed in strict isolation.
The schools are close to Vickery Meadows, a largely immigrant neighborhood where the Ebola victim lived with relatives.
"These children have been identified and they are being monitored and the disease cannot be transmitted before having any symptoms, Texas Governor Rick Perry said.
Clara Sheard said that one of the students removed from school was a classmate of her granddaughter who is in 7th grade.
"When I met her to walk her home she told me that they took one of one of the African students out of school and said that he couldn't come back," Sheard said.
Several students interviewed outside Emmet J. Conrad High School, where one student was sent home, said that they were aware of the Ebola epidemic in Africa but they were surprised to hear that the news is now happening so close to home.
"I didn't get paranoid," said Jazmin Edward, an 11th grader. "Our teachers were telling us to wash our hands and stay away from people, so that's what I'll do."
The high school wrote to tell parents that the child was not showing any symptoms.
- Symptoms of infection -
The incubation period for Ebola is between two and 21 days. Patients are not contagious until they start to have symptoms. Ebola can lead to massive bleeding and fatal organ failure.
A 10-member team of experts from the US Centers for Disease Control and Prevention has landed in Texas to assist the investigation.
While health experts say the public should not panic medical personnel are on the lookout for more cases of Ebola on US soil.
Three crew members who worked in the ambulance that transported the patient have tested negative, but they will be monitored for 21 days, the City Of Dallas said.
Anthony Fauci, the head of the National Institute for Allergy and Infectious Disease, said the man should have been identified as a suspected Ebola case the first time he sought care.
The 10,000-strong Liberian community in the Dallas area is concerned about the arrival of Ebola on US soil but remains confident in the medical authorities, said Alben Tarty, a spokesman for the Liberian Community Association of Dallas Fort Worth.
- Worldwide toll jumps -
As US officials scrambled to track down people, the worldwide death toll from Ebola jumped to 3,338 dead and 7,178 infected since the beginning of the year, the World Health Organization said.
Meanwhile, the United Nations announced its first suspected victim of Ebola, a Liberian man who worked for the UN mission in Liberia and died of a probable but unconfirmed infection last week.
In response to the fast-moving outbreak, the World Bank boosted its aid to the campaign by adding $170 million toward expanding the health-care workforce and buying needed supplies for care and treatment.
The new aid took to $400 million the amount the bank has put toward the fight against the spread of Ebola, which has swept quickly through Liberia, Guinea and Sierra Leone.