A second Dallas hospital worker who provided care for the first Ebola patient diagnosed in the U.S. has tested positive for the disease.

It is unclear how the second worker contracted the virus. 

From ABC News:

Authorities declined to say what position she holds at the hospital or the type of care she provided to Thomas Eric Duncan, who was diagnosed with Ebola after coming to the U.S. from Liberia. Duncan died Oct. 8.

Officials have said they also don’t know how the first health worker, a nurse, became infected. But the federal Centers for Disease Control and Prevention said “an additional health care worker testing positive for Ebola is a serious concern.”

“What happened there (in Dallas), regardless of the reason, is not acceptable. It shouldn’t have happened,” Anthony Fauci, director of the Institute of Allergy and Infectious Diseases of NIH, said on MSNBC Wednesday.

Read more at ABC News

The worker at Texas Health Presbyterian Hospital was monitoring herself for symptoms, and the woman reported a fever on Tuesday. Within 90 minutes, she was placed in isolation.

CDC head Dr. Tom Freiden acknowledged that the government was not as aggressive as it should have been in managing Ebola and containing the virus.

The second case may help officials determine where the infection control breach is occurring, so they can develop safer practices for health workers everywhere.

Officials say at least 76 people at the hospital may have been exposed to the virus. All are being monitored for fever and other symptoms.

Update: The victim, identified as Amber Vinson, flew a day before her diagnosis. Now, the CDC wants to monitor all 132 passengers and crew on the flight. Vinson did not have symptoms of the virus at the time of flight. Ebola is only contagious when an infected person is showing signs of the virus.

Check back for updates.

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