DALLAS — A health care worker at a Texas hospital who provided care for the Ebola patient who was hospitalized there, and later died, tested positive for Ebola in a preliminary test at the state public health laboratory in Austin, officials said Sunday in a statement.

A statement posted on the Texas Department of State Health Service’s website said “confirmatory testing will be conducted by the Centers for Disease Control and Prevention in Atlanta.”

According to the Dallas Morning News, Mayor Mayor Mike Rawlings will hold a news conference at 7:30 a.m. CT Sunday to discuss the lab test results.

Officials said the health care worker reported a low grade fever Friday night and was isolated and referred for testing. Preliminary test results were received late Saturday.

“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.”

Health officials have interviewed the patient and are identifying any contacts or potential exposures. They 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.

Thomas Eric Duncan, the first person diagnosed with Ebola in the U.S., died Wednesday in Dallas.