A second health care worker at Texas Health Presbyterian Hospital who cared for Thomas Eric Duncan has tested positive for Ebola, the state's health department said Wednesday.
The worker reported a fever Tuesday and was immediately isolated, health department spokeswoman Carrie Williams said.
The preliminary Ebola test was done late Tuesday at the state public health laboratory in Austin, and the results came back around midnight. A second test will be conducted by the Centers for Disease Control and Prevention in Atlanta.
"Health officials have interviewed the latest patient to quickly identify any contacts or potential exposures, and those people will be monitored," the health department said. "The type of monitoring depends on the nature of their interactions and the potential they were exposed to the virus."
But the pool of contacts could be small, since Ebola can only be transmitted when an infected person shows symptoms. Less than a day passed between the onset of the worker's symptoms and isolation at the hospital.
See more on this developing story on CNN.com.