WORCESTER, Mass. (AP) — A Massachusetts doctor cured of Ebola says he’s returning to the West African country where he contracted the deadly virus to help his overworked hospital colleagues.

Dr. Rick Sacra (SAY’-cruh), says he won’t normally be working directly with Ebola patients in Liberia but occasionally could be asked to do so. Doctors say he’s now immune to the disease.

Sacra’s wife, Debbie, says she’s glad he’ll only be gone about a month and understands his decision to return.

Sacra spoke Monday at the University of Massachusetts Medical School, where he’s a professor. He travels to Liberia on Thursday.

He contracted Ebola in August and was released from an Omaha, Nebraska, hospital in September.

Sacra has worked for years at ELWA, a hospital in the Liberian capital run by the North Carolina-based Christian organization SIM.