Ebola outbreak in DRC ‘not even close’ to being controlled

Issue: January 2019

Vaccination has helped control the Ebola virus outbreak in the Democratic Republic of Congo, or DRC, but ongoing violence and political instability in the region are complicating the response and the case count has continued to rise.

As of Jan. 1, the outbreak included 608 probable or confirmed cases and 368 deaths, according to the DRC health ministry, making it the second largest Ebola outbreak in history after the West African epidemic.

“We expect the outbreak to last for at least 4 more months,” DRC health minister Oly Ilunga Kalenga, PhD, told Infectious Disease News. Kalenga noted that the outbreak had been contained to two provinces — North Kivu and Ituri — and that it had not reached any neighboring countries or nearby major urban centers such as Goma, Bunia and Kisangani.

“However, the challenge with this outbreak is the unpredictable environment of the region so we cannot rest until we track the last Ebola case,” he said.

Importance of vaccination, treatment

According to WHO spokesman Tarik Jaarevi, the level of secondary transmission in outbreak hotspots has been low, an indication that the ring vaccination being conducted using Merck’s experimental Ebola vaccine “is having an important impact,” he told Infectious Disease News. As of Jan. 1, more than 54,000 people at risk had been vaccinated, including health and frontline workers. In addition, the neighboring countries of Uganda and South Sudan also began vaccinating health and frontline workers over fears of cross-border spread.

“Without the vaccine, this outbreak would have already been out of control because of the density and mobility of the population in the affected zones, and the level of community resistance we experienced in some areas,” Kalenga said. “Based on the number of high-risk contacts who have been vaccinated, we believe we would have already had more than 10,000 cases.”

It is the first time that a vaccine is being used to control an outbreak of Ebola. In another first, the DRC also began a pioneering randomized control trial to evaluate the effectiveness and safety of several drugs used to treat patients with Ebola.

Jaarevi reported that 203 patients through Dec. 11 had received the investigational therapeutics mAb114 (NIH), remdesivir (Gilead Sciences), ZMapp (Mapp Biopharmaceutical) or REGN-EB3 (Regenron) under a compassionate use protocol. Twenty-six additional patients received therapeutics under the recently launched randomized control trial in the town of Beni, which has seen the most cases, he said. There are no data yet showing how effective the experimental treatments are, Jaarevi said. According to a count provided by Kalenga, more than half of patients receiving experimental treatments have survived.

“Responding to the Ebola outbreak ... continues to be a multifaceted challenge,” Jaarevi said. “By using proven public health measures [including] contact tracing, engaging communities, as well as new tools at hand, [including] a vaccine and therapeutics, WHO remains confident the outbreak can be contained and brought to an end.”

‘Worrisome’ trends

According to Jaarevi, the epidemiological curve of the outbreak has shown two distinct phases. The first was centered in Mangina and was largely brought under control within a month.

“The second wave, dispersed across many areas, has continued for over 2 months, with approximately five new cases per day,” he said. “Based on current trends and the impact of the response, as well as our experience in previous outbreaks, we can see that there will continue to be transmission for several months.”

Jennifer B. Nuzzo, DrPH, a senior scholar at the Johns Hopkins Center for Health Security and visiting faculty in the department of environmental health and engineering at the Johns Hopkins Bloomberg School of Public Health, said the outbreak “is not even close” to being controlled.

“If you look at where we were at the end of September at about 150 cases, that is an enormous jump in cases in just a few months. The incidence trends are not headed in the right direction,” Nuzzo told Infectious Disease News.

Another reason for concern, she said, is that cases are appearing in areas where they had not previously occurred or where the number of cases had dropped.

“We don’t yet know why that is,” Nuzzo said. “We don’t know if it is purely because people went back into those areas and re-exposed those people or maybe the cases were occurring all along and we were missing them. Now, the geographic spread of cases is really going to be problematic. Now we have a larger area. There are more chains of transmission that are occurring over an area that we have to spread very limited resources to try to control it. That’s a very worrisome sign.”

In an article published in The New England Journal of Medicine, Nuzzo and Thomas V. Inglesby, MD, director of the Johns Hopkins Center for Health Security, called for a “ramping up” of the response, including a return to the field of CDC staff who were evacuated over concerns about security.

Armed clashes between opposition groups and the government have impeded the response, as have political protests over a delayed presidential election, including one in late December that spilled over into a transit center in the town of Beni — the epicenter of the outbreak — where people were waiting for Ebola test results, forcing patients and medical staff to withdraw.

“Applying the right resources to the problem can help,” Nuzzo said. “There had been a glimmer of hope in Beni and I think it shows what we can do with more resources. Unfortunately, we do not have enough resources. In particular, the U.S. CDC has been basically pulled out of responding. Other countries really have not contributed, although I think none have the knowledge and experience that the CDC has.

“I think it is kind of an urgent call to action right now to say, listen, this is not hopeless. Stuff can be done despite the very severe challenges. But we as a global community, particularly the United States, really need to step up.” – by Bruce Thiel

References:
Ebola control in Butembo: Africa CDC supports the local Coordination Prevention Commission https://au.int/en/pressreleases/20180920/ebola-contol-butembo-africa-cdc-supports-local-coordination-prevention. Accessed January 3, 2019.
Nuzzo JB, Inglesby TV. N Engl J Med. 2018;doi:10.1056/NEJMp1814296.

For more information:
Tarik Jaarevi, can be reached at jasarevict@who.int.
Oly Ilunga Kalenga, PhD, can be reached by contacting Jessica Ilunga at jessica.t.ilunga@gmail.com.
Jennifer Nuzzo, DrPH, can be reached at jnuzzo1@jhu.edu.

Disclosures: Jaarevi, Kalenga and Nuzzo report no relevant financial disclosures.