The director of the Centers for Disease Control and Prevention said the agency regretted its initial response to the first Ebola diagnosis in the United States, acknowledging that more could have been done to combat infection at the hospital treating the patient.

“We did send some expertise in infection control,” Thomas Frieden said during a news conference Tuesday. “But I think we could, in retrospect, with 20/20 hindsight, have sent a more robust hospital infection control team and been more hands-on with the hospital from day one about exactly how this should be managed.”

Frieden’s comments came two days after a nurse in Texas was diagnosed with Ebola, becoming the first person to contract the virus in the United States. She was infected while caring for Thomas Duncan, a Liberian man who flew to the country last month and fell ill days later. Duncan died last week.

In addition, Frieden said that authorities still do not know how she was infected, even as he said more than 70 people could have been exposed to Duncan while he was being treated at Texas Health Presbyterian Hospital.

Still, in response to this infection and to growing concerns from health-care workers and the public, the CDC will now send a team of experts “within hours” to any hospital that has a confirmed Ebola case, Frieden said.

This “Ebola response team” will have dedicated doctors, specialists in laboratory science, epidemiologists and others who will work to protect health-care workers from infection, helping with everything from the protective equipment used to the way patients and contaminated materials are moved, he said.

“I wish we had put a team like this on the ground the day the first patient was diagnosed,” Frieden said. “That might have prevented this infection [of the nurse]. But we will do that from today onward with any case anywhere in the U.S.”

Two nurses who treated Ebola patients at Emory University Hospital have traveled to Texas to consult about using protective equipment and other infection control measures, Emory announced Wednesday.

Nina Pham, the nurse who was diagnosed Sunday, remains in stable condition, Frieden said. She had direct contact with one person while she was symptomatic, the only time a person with Ebola is infectious, and that person has no symptoms and is being monitored.

Since it remains unclear how Pham was infected, authorities are looking at everyone who may have had contact with Duncan in the hospital, which included going into his room or handling any blood or other infected materials. They have found 76 people “who might have come into contact” with Duncan or his blood while he was hospitalized, Frieden said.

“I don’t want anyone to take out of this that there are 76 exposed people,” Frieden said. “There are 76 people who had some level of contact and therefore, they’re being actively monitored.”

That number does not include the 48 people who had direct or possible contact with Duncan before his hospitalization. None of these people have shown any symptoms, Frieden said.

The fact that they have gone this long without showing any symptoms is a very good sign, Frieden said. Duncan was isolated and hospitalized Sept. 28, which means it has been more than two weeks since any of them could have had contact with Duncan. Most infections happen much earlier in the process, so these people have passed by the most dangerous period, and it would be unusual if any of them were infected, Frieden said.

Tom Frieden, the director of the Centers for Disease Control and Prevention, urged world leaders to work quickly to combat the spread of the Ebola virus during a meeting on Thursday morning. (AP)