Ebola responders in Beni, a city in the Democratic Republic of the Congo, disinfect each other before entering the home of a woman thought to be infected with the virus.Credit: Zohra Bensemra/Reuters

Armed groups have killed four Ebola responders in the eastern Democratic Republic of the Congo (DRC) and injured five others, in a series of attacks that began late on 27 November, according to the World Health Organization (WHO).

The dead include a vaccination worker, two drivers and police officer, the agency said. Dozens of aid workers are being evacuated from the areas under siege, and the Ebola response there has mostly halted.

The attacks, in Biakato and Mangina, came after violence in nearby Beni prompted the WHO and aid groups to begin evacuating workers from that city earlier this week.

“We are heartbroken that people have died in the line of duty as they worked to save others from Ebola,” WHO director-general Tedros Adhanom Ghebreyesus tweeted on 28 November.

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One late-night attack by the grass-roots militia known as the Mai-Mai targeted the residence of Ebola responders in Biakato. The vaccination worker was one of several people killed there, according to the Centre of Study for the Promotion of Peace, Democracy and Human Rights, a DRC activist group.

The same night — 27 November — armed groups charged an Ebola-response coordination centre in Mangina, the WHO says. Police protecting the centre fought back, and one person was killed in the crossfire.

Dangerous situation

It is not clear whether the attacks in Mangina and Biakato are related to each other or to the continuing violence in Beni. An armed group called the ADF (Allied Democratic Forces) has terrorized residents there with machetes and knives over the past three weeks. Roughly 100 people have been killed and many more displaced, according to the Congo Research Group at New York University. The ADF is one of dozens of armed groups that operate in the DRC.

The WHO said earlier this week that the violence in Beni would probably cause the number of new Ebola cases to rise; the situation is poised to worsen with the evacuation of Ebola responders from Biakato and Mangina. Such workers normally circulate in communities to trace the contacts of people with Ebola, who they vaccinate and monitor for signs of infection.

Ebola has infected more than 3,300 people in the eastern Democratic Republic of the Congo (DRC) since August 2018 and killed nearly 2,200, according to the DRC government.

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The latest surge in violence has angered residents of Beni and nearby communities, who are upset that United Nations peacekeeping troops and DRC soldiers stationed in the city have not stopped the ADF attacks. On 25 November, street demonstrations against the UN spilled into one of the organization’s compounds near Beni, where protesters set a vehicle on fire. Soon afterwards, UN troops were evacuated from the city by helicopter.

Losing ground

The pause in the fight against Ebola is particularly discouraging to Marie-Roseline Darnycka Bélizaire, an epidemiologist coordinating the WHO’s response to the DRC outbreak. She had begun to let herself envision the end of the outbreak, because the number of new infections reported each week has dwindled steadily since October.

Before the latest violence erupted, Ebola responders had been able to bring many sick people to treatment centres within 24 hours of the first symptoms of infection. There, those who are ill receive drugs that can cure up to 90% of Ebola cases if given soon after infection — and they are prevented from transmitting the virus to others.

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Now Bélizaire fears that more than a year of hard work by Ebola responders could be undone. Two people have been diagnosed with the virus in Beni and nearby Oicha amid the unrest — and Ebola responders haven’t been able to track chains of transmission.

“We were so close,” Bélizaire said on 25 November as she readied a WHO facility in Mangina for an influx of Ebola responders from Beni, which is 40 minutes away.

Some Ebola responders are fearful that they, too, could be injured or killed by armed groups. But Bélizaire said they will keep pushing to end the outbreak nonetheless.

“Most of us are energized,” she said. “We want to stay in the field and finish the job.”

Days later, Ebola responders in Mangina came under attack. In a text message to Nature on 28 November, Bélizaire said that she had begun to organize the evacuation of Ebola workers there.