BUTEMBO, Congo >> The woman spent more than a week at home sick before family members tried to take her to an Ebola treatment center in eastern Congo. Before the motorcycle could reach the facility, it was too late.

Her crumpled body rested against the driver’s back as he worriedly made phone calls, witnesses said.

Health experts are expressing growing alarm about the number of people sickened with the Ebola virus who are never reaching treatment centers, allowing the disease to spread to caregivers and countless others.

Monday set a new record in this outbreak of 27 confirmed cases in a single day, Congo’s health ministry said. Over the past four days 93 cases had been confirmed.

The World Health Organization said 126 new confirmed cases were reported over a seven-day stretch ending on Sunday, the largest such tally in this outbreak that was first declared in August. Fifteen deaths were reported on Sunday alone, marking the highest number of deaths reported on a single day in the outbreak.

In an email, WHO spokesman Tarik Jasarevic sought to play down the significance of the higher figures, saying the case numbers were “better interpreted as an increase in case activity within the outbreak hotspot areas.”

“We discourage phrasing this as ‘record numbers’ or similar as it does not reflect well current activity/data, and provides an unnecessarily alarmist view of the outbreak,” he wrote.

The fact that many are dying outside the health care system means the full scale of the crisis is unknown.

“There might be double this many cases in reality that we’re just not aware of,” said Tariq Riebl, emergency response director for the Ebola response crisis with the International Rescue Committee.

“A very small number are actually presenting themselves to health centers,” he said.

WHO’s Jasarevic said 38% of people who died over the seven-day period ending Sunday had died before reaching Ebola Treatment Centers, down from more than 60% about two months ago.

Distrust of health workers, combined with a highly volatile security situation at the outbreak’s epicenter, is putting the Ebola response in serious peril.

The spike in recorded cases has been attributed to a series of attacks that have hampered health workers’ efforts to go out into the affected communities to educate and vaccinate.

On April 19, a Cameroonian epidemiologist working with WHO was killed during an attack on a hospital in Butembo city. Two other health workers were injured.

The IRC said it has had to curtail its triage efforts in those areas as a result. Doctors Without Borders has also pulled out temporarily, leaving the health ministry to run the treatment centers there.

Health experts have attributed the community resistance to the fact that eastern Congo has suffered a quarter-century of armed conflict, leading to a deep mistrust of government officials who are now running the treatment centers.

Voters in Ebola hotspots also were unable to vote in the January presidential election, deepening false suspicions that Ebola had been brought to the region for political gain.

There now have been 957 deaths among the 1,466 confirmed and probable cases reported in this outbreak, WHO said.