2nd Person in US Tests Positive for Ebola
A scanning electron micrograph of the Ebola virus.
Credit: Cynthia Goldsmith | CDC

A second person in Dallas has tested positive for Ebola after coming in contact with a man from Liberia who was infected with the deadly virus, officials said today.

This second patient is a health care worker at Texas Health Presbyterian Hospital, and helped care for Thomas Eric Duncan, the first person to be diagnosed with Ebola in the United States, according to the Texas Department of State Health Services.

The health care worker came down with a fever Friday night, and a preliminary test was positive for Ebola, officials said. The Centers for Disease Control and Prevention will perform a second test to confirm the results. This testing is underway and will be completed later today, Dr. Tom Frieden, director of the CDC, said in a news conference today. [Ebola Virus: 5 Things You Should Know]

The second patient had extensive contact with Duncan during his care, Frieden said. Health officials don't know how the health care worker became infected, but "at some point there was a breach in protocol, and that breach in protecol resulted in this infection," Frieden said. There will now be a complete investigation to understand how this infection might have occured, and prevent it from happening in the future, he said.

"It is certainly very concerning," Frieden said, referring to the possible new case. "It tells us that there is a need to enhance training and protocols to make sure the protocols are followed," he said. Frieden noted that even a single slip can result in infection.

Some high-risk situations for contracting the Ebola virus are when health care workers perform kidney dialysis and respiratory intubation of infected patients, and when health care workers take off personal protective equipment, Frieden said.

The CDC had previously said it was monitoring about 48 people who had contact with Duncan before he was isolated. The second Ebola case was not one of these original 48 people — she was monitoring herself, and sought care when she developed symptoms, Frieden said. Now health officials will formally monitor people who had contact with Duncan during his care, and will identify people who had contact with the second case after she started to show symptoms, Frieden said. So far, it appears that only one person had contact with the second case while she may have been infectious, he said.

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

Ebola is spread through contact with the bodily fluids, such as blood or secretions, of an infected individual, or by contact with contaminated objects. People with Ebola are only contagious after they start showing symptoms.

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