An American physician who was exposed to the Ebola virus is expected to be admitted to the National Institutes of Health in Bethesda, Md., in the coming days, the research agency said in a statement Saturday afternoon.

The patient, who was volunteering in an Ebola treatment unit in Sierra Leone, will be admitted for observation and to enroll in a clinical study at a center “specifically designed to provide high-level isolation capabilities.” The action is being taken “out of an abundance of caution,” the NIH said, adding that it “is taking every precaution to ensure the safety of our patients, NIH staff, and the public.”

It stressed that “this situation is of minimal risk to NIH staff and the public.”

The NIH did not release the patient’s name or any more information about his or her condition. Officials said the patient could arrive as early as Sunday.

Just because someone is exposed to the deadly virus, it “doesn’t necessarily mean they are infected,” said Anthony S. Fauci, the director of the National Institute of Allergy and Infectious Diseases at the NIH.

The spread of the virus is the largest Ebola outbreak in history and the first such outbreak in West Africa, according to the Centers for Disease Control and Prevention. The risk of an outbreak in the United States is “very low,” the CDC said.

As of Friday, 3,083 deaths in Guinea, Liberia and Sierra Leone have been attributed to the virus, according to the World Health Organization.

The CDC has warned that the virus could potentially infect 1.4 million people in Liberia and Sierra Leone by the end of January. And a recent report in the New England Journal of Medicine said that the virus could become endemic in the hardest-hit countries in West Africa.

The United States, however, has launched a $750 million effort to create treatment facilities in Liberia. And this month, the U.N. Security Council voted to create an emergency medical mission to help stem the outbreak.

Also this month, the Liberian government, the WHO and nonprofit partners are preparing to start a program to move infected people out of their homes and into ad hoc centers in an effort to try to stem the disease’s spread. The goal is to prevent the patients from infecting their families and to offer at least basic care — food, water and pain medicine — with many hospitals closed.

In Liberia on Saturday, the country’s chief medical officer announced that she would quarantine herself after her office assistant died of Ebola, the Associated Press reported.

Bernice Dahn, a deputy health minister who has represented Liberia at regional conferences on combating the epidemic, told the AP that she did not have Ebola symptoms but wanted to ensure she is not infected.

She said she would put herself under quarantine for 21 days, the virus’s maximum incubation period.

“Of course we made the rule, so I am home for 21 days,” Dahn said. “I did it on my own. I told my office staff to stay at home for the 21 days. That’s what we need to do.”

In Guinea, officials said Saturday that the country’s appeals court had been closed until further notice after a staffer there died of Ebola, the AP reported.

“All the records of the department passed through the hands of this woman,” an official said.

The patient to be admitted to the NIH is one of a few to be taken to hospitals in the United States. Earlier this week, Richard Sacra, a missionary doctor who was working in Liberia, was released from the Nebraska Medical Center after contracting the virus.

Two other Americans have been discharged after they were successfully treated in the United States for Ebola, including another doctor, Kent Brantly, who later donated a unit of blood, or convalescent serum, to Sacra.

Abby Phillip contributed to this report.