A health worker wears Ebola protection gear in the Democratic Republic of Congo, where more than 2,000 people have now been infected with the disease.Credit: Baz Ratner/Reuters

The number of Ebola cases in the Democratic Republic of the Congo (DRC) has doubled in just over two months and has now passed 2,000, according to the World Health Organization (WHO).

An estimated 2,008 people have been infected with Ebola in the North Kivu and Ituri provinces since the start of the outbreak in late July 2018, and 1,346 of those individuals have died. The numbers represent a rapid escalation of the crisis since the outbreak passed the 1,000-case mark on 24 March (see ‘Escalating crisis’).

“I’m profoundly worried,” Tedros Adhanom Ghebreyesus, the WHO’s director-general, told Nature in May. He attributes the failure to end the outbreak to mistrust of and assaults against Ebola responders — problems that have worsened this year. “The number of cases increases with the frequency of attacks,” he says.

Source: WHO

‘The wrong direction’

The steep increase in cases signals that the spread of Ebola in the DRC is far from under control. “Despite WHO’s extraordinary efforts to contain the outbreak, the transmission trends have moved in the wrong direction in recent weeks,” an independent committee of researchers overseeing the WHO’s response wrote in a report presented at the World Health Assembly in Geneva, Switzerland, on 21 May. Although the committee expressed confidence in the WHO’s leadership, they raised concerns about staff exhaustion and the complexity of tackling an Ebola outbreak amid conflict.

Violence has plagued North Kivu for decades, and the region is home to dozens of armed groups and communities who oppose the government. Political tensions grew late last year during elections, when the DRC’s former president banned more than a million people in North Kivu from voting because of Ebola. The measure led many people to suspect that the outbreak was a political invention to marginalize the opposition, and not a real disease.

But authorities cannot tackle Ebola if people mistrust their intentions. Health workers must convince people to send their family members to treatment centres, for instance, and persuade people to receive an experimental Ebola vaccine. Despite continuous outreach, many people remain suspicious of Ebola responders — who are often not from the region — and a small fraction assault health workers﻿.

Rising violence

Such incidents have increased this year. The WHO reports that there have been 174 attacks against health-care facilities or workers in North Kivu so far in 2019 — a threefold increase compared with the last five months of 2018.

The danger posed by such attacks prevents Ebola responders from working in communities, meaning that they are unable to perform a key part of control efforts: tracking contacts of people who have contracted the disease. This allows the virus to spread undetected, and results in infections among people who weren’t being monitored as contacts. In the week following the murder of a WHO epidemiologist in April, for example, more than 70% of people diagnosed with Ebola were not listed as contacts of people with the disease.

This rate has improved in the past few weeks as Ebola responders seek out people at risk and meet with community leaders, but attacks still loom. Tarik Jašarević, a WHO communications officer in Geneva, stresses the magnitude of effort expended by responders in the thick of it. “On average our surveillance teams need to try to reach 20,000 people daily,” he says, “﻿and this is not always possible especially when violence breaks out.”