Texas health care worker tests positive for Ebola

David L. Lakey (L), Commissioner of Texas Department of State Health Services, speaks at a media conference at Texas Health Presbyterian Hospital in Dallas, Texas, October 1, 2014.
Mike Stone | Reuters

A Dallas health care worker who provided care for the Ebola patient hospitalized there has tested positive for the virus in a preliminary test, state and federal officials said on Sunday, becoming the second person on U.S. soil to contract the deadly disease ravaging parts of Africa.

The worker, based at the Texas Health Presbyterian Hospital where Liberian national Thomas Eric Duncan eventually succumbed to the disease, reported a low grade fever Friday night and was isolated. The preliminary ​exam indicated she had in fact contracted the debilitating virus.

"We knew a second case could be a reality, and we've been preparing for this possibility," said Dr. David Lakey, commissioner of the Texas Department of State Health Services. "We are broadening our team in Dallas and working with extreme diligence to prevent further spread."

According to health workers, the nurse, whose name was not released, was wearing protective gear when she treated Duncan. If accurate, it challenges the narrative advanced by public health officials that Ebola can't be spread through casual contact.

"This development is understandably disturbing news for the patient, the patient's family and colleagues and the greater Dallas community," said the Centers for Disease Control, in a statement confirming the news.

"The CDC and the Texas Department of State Health Services remain confident that wider spread in the community can be prevented with proper public health measures, including ongoing contact tracing, health monitoring among those known to have been in contact with the index patient, and immediate isolations if symptoms develop," the agency added.

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Health officials have interviewed the patient and are identifying any contacts or potential exposures, the statement said. People who had contact with the health care worker after symptoms emerged will be monitored based on the nature of their interactions and the potential they were exposed to the virus, it added.

Duncan died in an isolation ward of the Dallas hospital on Oct. 8, 11 days after being admitted. He was exposed prior to departing from his country, and was widely suspected to have misrepresented whether he had come into contact with anyone suffering from the virus.

The U.S. government has since ordered five airports to start screening passengers from West Africa for fever, including New York's John F. Kennedy International Airport.

The number of people known to have died in the worst Ebola outbreak on record has risen to 4,033 out of 8,399 cases in seven countries, the World Health Organization said on Friday.

Liberia has been the worst affected country with 2,316 victims, followed by 930 in Sierra Leone, 778 in Guinea, eight in Nigeria and one in the United States, WHO said.

Reuters contributed to this story