SUAKOKO, Liberia — For days this month, the ambulances from the Ebola treatment unit here went out in search of patients, only to return with just one or two suspected cases. And many times, those people ended up testing negative for the disease.

“Where are the patients?” an aid worker wondered aloud as colleagues puzzled over the empty beds at the International Medical Corps treatment unit here in Bong County, Liberia, which opened in mid-September.

Around the country, treatment centers, laboratory workers who test for Ebola, and international and national health officials trying to track the epidemic have noticed an unexpected pattern: There are far fewer people being treated for Ebola than anticipated.

As of Sunday, fewer than half of the 649 treatment beds across the country were occupied, a surprising change in a nation where patients had long been turned away from Ebola units for lack of space.