WASHINGTON — The government is telling the nation’s hospitals to ‘‘think Ebola.’’

Every hospital must know how to diagnose Ebola in people who have been in West Africa and be ready to isolate a suspected case, Tom Frieden, director of the Centers for Disease Control and Prevention, said Monday.

He said the CDC is working to improve protections for hospital workers after a nurse caring for an Ebola patient in Dallas became the first person to become infected with the disease inside the U.S.

‘‘We have to rethink the way we address Ebola infection control,’’ Frieden said, ‘‘because even a single infection is unacceptable.’’


The CDC is scrambling to interview all staff of the Dallas hospital who could have been exposed to the patient, a Liberian man who became sick after traveling to the United States and died at the hospital. Anyone at risk will be monitored, he said.

Before the nurse’s illness, those who cared for that patient while he was in isolation were told to check themselves for fever or signs of illness but weren’t monitored by health officials. The nurse self-reported her fever.

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‘‘We need to consider the possibility that there could be additional cases, particularly among the health care workers who cared for the index patient’’ — the Liberian man — ‘‘when he was so ill,’’ Frieden said.

Ebola patients aren’t contagious until they begin experiencing symptoms, Frieden said. As they get sicker, they become more infectious and the amount of virus in their bodily fluids increases — putting those caring for them at greater risk.

The CDC already was monitoring about 50 people who had contact with the patient, Thomas Eric Duncan, before he was hospitalized. None have developed symptoms. They are still within the 21-day incubation period, however.


Frieden said the CDC is doubling down on Ebola training and support for hospitals and health care workers. But they still don’t know exactly how the nurse, whose name was not released, was exposed to the virus despite wearing the recommended protective gear.

On Sunday, Frieden said she apparently became infected through some breach in the protocol for caring for Ebola patients. On Monday, Frieden offered an apology to health care workers who complained that it sounded like he was blaming the nurse instead of questioning whether the protocols and training she received were sufficient.

‘‘I feel awful that a hospital worker became infected taking care of an Ebola patient,’’ Frieden said.

Frieden said CDC workers were at the Dallas hospital helping to make safety improvements as the staff member is treated.

Hospital workers across the country are the front line against Ebola, he said.

‘‘The single most important thing for every hospital to know is taking a history of travel,’’ Frieden said. He said people who have been to Liberia, Sierra Leone or Guinea within the last 21 days and are exhibiting Ebola-like symptoms should immediately be placed in isolation.

Earlier in the day, a top federal health official said authorities should consider requiring Ebola patients to be sent only to specialized ‘‘containment’’ hospitals.

Dr. Anthony Fauci, who heads the National institute of Allergy and Infectious Disease, told ABC’s ‘‘Good Morning America’’ that it’s something that ‘‘should be seriously considered.’’

Health officials are stepping-up the monitoring of hospital workers in Texas who provided care to the first person diagnosed with Ebola in the US One of those workers became infected with the virus, despite wearing protective gear.


It raises questions about the assurances given by health officials in the United States that the disease will be contained, and that any American hospital should be able to treat it.

The patient who was being treated, Thomas Duncan, had traveled from Liberia to visit family. He didn’t get sick until he arrived in the United States. He died Wednesday.

Police have been knocking on doors and making automated phone calls in the neighborhood where the health care worker lives. But Dallas authorities are assuring residents that the risk is confined to those who have had close contact with the two Ebola patients.