Hospital officials say a New York doctor who became infected with Ebola while treating patients in Guinea has been upgraded from serious but stable to stable condition.

The New York City Health and Hospitals Corporation issued the upgrade for Dr. Craig Spencer on Saturday morning.

The agency runs Bellevue Hospital Center, where Spencer has been undergoing treatment since he was brought there nine days ago.

The HHC has said Spencer is receiving therapies that have been effective in treating Ebola patients at Emory University Hospital in Atlanta and at the Nebraska Medical Center.

Spencer is the only confirmed Ebola patient in New York.

His case led governors in New York and New Jersey to declare a mandatory quarantine for travelers exposed to Ebola in West Africa.