October 15, 2014 5:43 AM EDT

A second Texas health care worker involved in treating a Liberian patient who died of Ebola has tested positive for the disease, officials said Wednesday, marking the second such worker and third person overall to be diagnosed with the virus on U.S. soil in the past several weeks.

The worker was identified by a family member as registered nurse Amber Joy Vinson, the Dallas Morning News reports, citing her grandmother. Vinson, 29, helped care for Thomas Eric Duncan, an Ebola patient who died one week ago at Dallas’ Texas Health Presbyterian Hospital after he was diagnosed with the disease following travel from Liberia.

She was isolated within 90 minutes after reporting a fever on Tuesday, whereupon she was tested for Ebola, Dallas County Judge Clay Jenkins told reporters Wednesday, adding “the protocol to find the virus worked well.” The results returned positive from a state lab in Austin around midnight, according to a statement from the Texas Department of State Health Services.

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“Health officials have interviewed the latest patient to quickly identify any contacts or potential exposures, and those people will be monitored,” said the Texas DSHS in its statement.

Authorities are moving swiftly to decontaminate the newly diagnosed patient’s apartment as well as the area around it. Dallas Mayor Mike Rawlings said Wednesday morning he anticipates the cleaning will be done by Wednesday afternoon. Officials are calling residents and distributing pamphlets in the area of the patient’s apartment to notify them about risks posed by the virus.

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The U.S. Centers for Disease Control and Prevention (CDC) has been roiled by allegations that it bungled setting appropriate safety protocols for treating Duncan after a nurse treating him contracted the Ebola virus last week. A top nurses union has spoken out about the problems that need to be resolved at the hospital where the 26-year-old nurse, Nina Pham, contracted the illness.

The CDC has acknowledged it did not move fast enough to set protocols at the Dallas hospital when the virus was first reported there, and it has pledged to better its response in the event of future cases.

Texas Health Presbyterian has also come under fire after two health workers have contracted Ebola caring for just one patient. No health workers have become ill after treating several patients for Ebola at Nebraska Medical Center and Emory University Hospital in Atlanta.

However, Chief Clinical Officer for Texas Health Resources Dr. Daniel Varga said that the new Texas patient’s speedy isolation is evidence that the local monitoring program is working effectively. “I don’t think we have systematic institutional problem,” Varga said. “The case of this patient here shows that our ability to intake [those affected] and isolate them has been very effective.”

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Write to Elizabeth Barber at elizabeth.barber@timeasia.com.

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