A member of a burial team lowers the body of a deceased woman Wednesday at King Tom Cemetery in Freetown, Sierra Leone. (Nikki Kahn/The Washington Post)

Despite some progress in the effort to halt the Ebola epidemic in West Africa, global health organizations have far to go to meet a self-imposed Dec. 1 deadline for isolating patients with the deadly disease and safely burying those who die of it, according to a World Health Organization report released Wednesday.

Global health officials had come up with a “70-70-60” plan, aiming to have 70 percent of Ebola victims isolated in hospitals or clinics, and 70 percent of burials conducted in a safe manner by specially trained teams, within 60 days. The plan, announced in early October by Bruce Aylward, a top WHO official, aims for 100 percent success by the first of the year.

That now appears to be a stretch.

The isolation goal has been reached in Guinea, where 99 percent of Ebola patients are in isolation, according to the latest update. But in Sierra Leone, only 40 percent have been isolated, and in Liberia only 23 percent isolated, according to the WHO. Officials believe they need 370 burial teams operating in the three countries, but so far have only 131 teams, not counting military units.

This is the largest outbreak of the Ebola virus in history.

The statistics in this outbreak have been notoriously iffy, and the WHO hedged on whether it might still reach its Dec. 1 target. “Uncertainties in data preclude firm conclusions” about progress toward the goals, the new Ebola report said.

The broader picture of the epidemic is mixed. The transmission rate has clearly dropped from the furious levels of August and September, and the worst-case scenarios — including the possibility of 10,000 new Ebola cases every week by the beginning of December — are now implausible.

But there continue to be about 600 new Ebola cases every week in the three countries most affected, “with widespread and intense transmission,” the new WHO report stated.

The WHO reported that in all countries, including Mali, Nigeria, Spain and the United States, there have been 15,935 cases so far in this Ebola outbreak, including 5,689 deaths. The epidemic, which began late last year in Guinea, reached historic proportions in the summer when the virus entered large cities, quickly overmatching the health care systems in West Africa and outracing the response from the global health community.

A broad campaign to change behaviors that enabled the spread of the Ebola virus, such as washing of corpses and other traditional burial practices, appears to have helped bend the infection curve since September. The infection rate dropped precipitously in Liberia in October, in advance of a major deployment of U.S. military personnel assigned to build Ebola Treatment Units.

But the Liberia numbers have leveled out for the past month. In recent weeks, Montserrado County, which includes the capital city of Monrovia, has seen 20 or even 25 new Ebola cases officially recorded in a single day, according to statistics from the Liberian Ministry of Health.

It is the nature of Ebola that it has to be throttled completely to end an outbreak; in the past, it has subsided and flared anew.

Another Ebola update released Wednesday, this one from the U.N. Mission for Ebola Emergency Response (UNMEER), reported that burial workers have gone on strike in the city of Kenema in Sierra Leone and dumped 15 bodies outside the city’s main hospital, including two at the main entrance. The BBC reported that the workers said they hadn’t been paid promised allowances for handling Ebola victims. The workers were fired for their conduct, the BBC reported.

In Monrovia, Chinese army doctors will staff a newly finished 100-bed Ebola Treatment Unit, with patients arriving next week, UNMEER reported. The U.S. military is also building ETUs in Liberia, but civilians rather than military doctors will staff them.

There was also news Wednesday of incremental progress in the search for an Ebola vaccine. Researchers at the National Institutes of Health have finished a phase 1 trial showing that a candidate Ebola vaccine is safe to use in human beings, according to a report in the New England Journal of Medicine. Larger human trials will be needed to determine if the vaccine will be effective in preventing Ebola infection.