SUAKOKO, Liberia — For days this month, the ambulances from this Ebola treatment unit 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.
Now, new admissions to treatment centers are dropping or flatlining, the number of samples being submitted to Ebola laboratories has fallen significantly, and the percentage of people testing positive for the disease has dropped as well.
“The numbers are decreasing, but we don’t know why,” said Malin Lager, a spokeswoman at a Doctors Without Borders treatment center just outside Monrovia, the capital. Its vast campus of white tents, which has a capacity for 253 patients, had only 90 on Sunday.
“It’s too early to celebrate,” Ms. Lager said.
Liberia has long been a focal point of the Ebola epidemic, the nation with the most cases and deaths from the disease, prompting a global call to action. Hundreds of new beds have been added in recent weeks, but now many are going unfilled even before any of the 18 treatment centers being built by the American military have opened, leaving many officials here confounded.
Some are debating whether the World Health Organization’s dire warnings about the epidemic — that there could be as many as 10,000 new cases each week in West Africa by December, about 10 times the rate it recently reported — might be grossly inflated.
“The projections were based on nothing happening” to curb the outbreak, said the United States ambassador to Liberia, Deborah R. Malac, during a visit to the International Medical Corps treatment center this month. “More things are happening every day.”
For now, most officials are continuing to plan for the worst so as not to interfere with the mounting international response, which is seen as critical to preventing a resurgence. Even a single unsafe burial, in which mourners touch a highly infectious corpse, can result in dozens of new cases.
The empty beds in Liberia come in the context of an intense public health campaign to educate the nation about the dangers of the disease and ways of combating it — from posters and billboards to messages broadcast when residents make phone calls.
“Lonestar Cell cares about your health. Ebola is real,” one company’s recording says.
Some consider the latest developments an indication that the efforts to combat the virus, including the opening of new treatment units, are beginning to succeed.
But because Liberians celebrated early once before — believing the virus had been eradicated in the spring, only to see it rage back with greater force in the summer — there is a near universal hesitance to call the outbreak under control. Liberia’s neighbors, Sierra Leone and Guinea, have been experiencing a troubling surge of cases in recent weeks.
There is also the likelihood that many people dying of Ebola in Liberia are hidden from the authorities, as has been true throughout the epidemic.
Many parts of the country are not well monitored, many contacts of Ebola patients are not traced, and officials have long acknowledged that the statistics on the numbers of Ebola cases across West Africa are rough estimates, at best.
Treatment beds and laboratories in Liberia are also concentrated in the capital. Large swaths of the country are hours away from these centers on bad roads, in areas that lack cellphone services, which is why the new treatment centers being built far from other Ebola facilities are considered so important.
Many of the monitoring experts, too, are based in the capital. Months into the crisis, officials still remind themselves of the need to get out into the wider country to test their assumptions about the epidemic. But even in the capital, many Ebola patients are suspected to have died at home, leaving big gaps in data on the scope of the disease.
Anna Halford, a field coordinator for Doctors Without Borders, said the charity had a broad network of community members who promoted Ebola awareness in and around the capital.
“Not a single one of the supervisors believes there is a significant drop in cases,” she said.
Families may keep sick relatives at home for many reasons, including rumors of mistreatment inside Ebola units and fears of quarantine and stigma, Ms. Halford said. Beyond that, “It is a disease that comes in waves because of the variability of the incubation period and because of the mobility of people.”