Though physicians believe Sacra’s illness is most likely not a recurrence of Ebola, doctors at UMass Memorial Medical Center are following guidance from the Centers for Disease Control and have isolated him to test for the deadly virus and determine his illness, the hospital confirmed. Hospital officials said determining his illness should take up to 36 hours.

Dr. Richard A. Sacra, who was treated for and declared free of Ebola virus in Nebraska nine days ago, was hospitalized in isolation Saturday in Worcester with what doctors said is probably a respiratory tract infection and is being monitored for an Ebola relapse.


“Dr. Sacra is in stable condition and being monitored carefully. We’re waiting for final test results from the CDC, which we expect to receive late Monday,” said Dr. Robert Finberg, an infectious-disease expert leading Sacra’s team of doctors.

“We think it is highly unlikely that he has Ebola. We suspect he has an upper respiratory tract infection, with symptoms of cough and conjunctivitis,” Finberg said.

Sacra had been treated for the virus at the Nebraska Medical Center, and was discharged on Sept. 25. While recovering at his home in Holden, he suffered from a persistent cough and low-grade fever and was initially concerned that he might be developing pneumonia, according to a statement from SIM USA, the missionary group Sacra worked with in Liberia.

“Out of an abundance of caution,” Sacra decided to go the hospital for an X-ray, officials at the Nebraska hospital said.

“Because of his recent battle with the Ebola virus, his immune system is compromised,” said Dr. Phil Smith, medical director of the Nebraska hospital’s biocontainment unit and one of the doctors who treated Sacra. “Dr. Sacra had three CDC-confirmed blood tests before he left our unit that showed him to be virus-free, so the public shouldn’t be concerned that his disease has returned.”


In a statement, SIM USA President Bruce Johnson said, “We are finding that full recovery from surviving Ebola can be long process, with the possibility of unrelated, but secondary health issues developing along the way.”

Johnson added that his organization is looking “forward to Rick’s return to full health in the days ahead.” He said Sacra’s family has asked for privacy.

Peggy Thrappas, a spokeswoman for UMass Memorial Medical Center, said the hospital is working closely with the CDC and the Massachusetts Department of Public Health and “carefully following specific plans and guidelines for the management of patients with suspected Ebola.”

“There is no risk to the general public and all appropriate precautions are being taken to protect the patient’s caregivers,” Thrappas said in a statement Saturday.

In an interview Saturday, DPH spokeswoman Anne Roach said there are no confirmed Ebola cases in Massachusetts and that the department has been working with hospitals for the past several months on preparedness.

That includes offering guidance for hospitals to move “with an abundance of caution,” she said.

“DPH has been working with several suspect cases – and ‘suspect’ is a very broad, broad category – and the cases thus far have all been ruled out,” said Roach, whose comments did not cover the Sacra’s case.

A spokeswoman for Massport, which runs Logan, said the agency has not been involved in the Worcester case. The CDC did not respond to requests for comment Saturday night.


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Anne Steele can be reached at anne.steele@globe.com. Follow her on Twitter @AnneMarie Steele. Alyssa Creamer can be reached at alyssa.creamer@globe.com. Follow her on Twitter @lisacreamer.