The World Health Organization (WHO) recently declared an international health emergency for the ongoing Ebola outbreak in the Democratic Republic of Congo (DRC) after a case appeared in a highly populated city with global air travel. The outbreak began in August 2018, and the WHO declared a Public Health Emergency of International Concern on July 18, 2019.1

In declaring an international emergency, the WHO is calling for international aid and assistance while emphasizing that it would be counterproductive to shut down travel to the region.

“One of the reasons they held off in making the emergency declaration, even though many people felt the conditions had been met previously, was out of fear that countries would implement travel and trade restrictions,” says Jennifer B. Nuzzo, DrPH, SM, a senior scholar at the Johns Hopkins Center for Health Security in Baltimore. “Everybody thinks that is a bad idea. That is not the way you try to control the spread of Ebola. It can really slow down the response because aid workers, supplies, and other resources can’t get into the region where they are needed.”

The WHO acted after the first reported case in Goma, a city of 2 million people on the border with Rwanda. That raised the potential for Ebola to spread to other regions on the continent. It also could open a path out of Africa for the deadly virus. For example, flights from Goma to Ethiopia can connect for travel to the U.S., Europe, and Asia. The incubation period for Ebola is two to 21 days, with most cases showing symptoms at eight to 10 days.

As confirmed on July 14, the case was a man who traveled to Goma by bus and visited a local clinic for illness.

“He transferred the same day to the Ebola Treatment Centre [ETC] in Goma, and died while being transferred to the ETC in Butembo,” the WHO reported.

While the outbreak response in the DRC has been undermined by civil unrest and violence, Goma has a public health presence that includes advisors from the CDC, Nuzzo says.

“[The CDC] was able to participate in the Goma investigation, and they found that some of the PPE that was used in evaluating this patient had been taken home [by caregivers],” she says. “Those are the kinds of problems that may go unnoticed unless you have a very keen eye on what is going on. That is enormously helpful. If there is any good news, I think it is the occurrence of cases closer to where the CDC personnel are located.”

Johns Hopkins is one of 10 designated Ebola treatment centers in the United States that have enhanced capabilities such as designated biocontainment units and other control and treatment measures.

The 2014 outbreak in West Africa was characterized by a lot of confusion about personal protective equipment (PPE), particularly the finding that healthcare workers frequently contaminated themselves doffing the equipment. That may have been a factor in the case of two Dallas nurses who contracted Ebola but survived after caring for a dying patient from West Africa. The basic PPE needed is considerable in the new tiered system in the United States, even for frontline hospitals that will be looking to quickly hand off a patient to one of the Ebola assessment facilities.2 (For more information, see the April 2019 issue of Hospital Employee Health.)

50 HCWs Killed by Ebola, Violence

Intensive follow-up of contacts of the confirmed case in Goma revealed no signs of subsequent transmission as this report was filed. Nineteen health workers were deployed from other posts to Goma to provide support in the response to this case, the WHO said. “There are currently no confirmed cases of EVD outside of the Democratic Republic of the Congo,” the WHO emphasized.

As of July 21, 2019, there were a total of 2,592 Ebola cases in the DRC, and 1,743 have died. Tragically, 737 of the total cases are children younger than 18 years. A total of 140 healthcare workers are affected.3

Unverified reports indicate at least 40 healthcare workers have died of Ebola. In addition, marauding militia groups vying for control of the region have attacked healthcare workers in some 200 incidents, resulting in seven deaths and 58 wounded.4 Given these circumstances, it has been difficult for the CDC and other response teams to fight the outbreak on the frontlines in the DRC.

“You hear a lot about the security constraints and challenges, and those are clearly there. But there are also deficiencies in the response that have not been fully identified,” Nuzzo says. “I think CDC and others have felt that not being in the field truly has hindered their ability to diagnose those problems and suggest fixes.”

The CDC issued a statement of support for the WHO declaration, saying it has opened its emergency response center and deployed personnel to Africa.

Is Ebola Vaccination Effective?

As previously reported, healthcare workers are receiving the experimental Ebola vaccine, but the efficacy of immunization was not clear as this report was filed. The WHO reported an incident in which two healthcare workers were infected with Ebola despite receiving the vaccine. It demonstrated high efficacy in a one trial,4 but now is administered on an unprecedented scale.

“Studies so far have suggested a very high rate of vaccine effectiveness, but you can envision there are some people who won’t have a protective response as the numbers get larger,” Nuzzo says. “In many of these cases, it is more likely they were vaccinated too close to when the exposure occurred. They weren’t able to mount a full protective response. Sometimes, they have been vaccinated after an exposure.”

There have been reports of nosocomial transmission in healthcare settings and treatment centers, but the proportion of these cases within the overall outbreak is unclear.

“In some cases, it is healthcare workers getting sick and treating patients,” Nuzzo says. “In other cases, it is a patient going to a health facility for entirely different reasons and they end up sitting next to an [undiagnosed] Ebola patient. These might be places like smaller health clinics where people are bringing their kids for malaria treatment or something else.”

Efforts to ensure a steady flow of PPE and reinforce proper use have been mixed.

“Purchasing additional PPE doesn’t necessarily lead to systemic change in behaviors and practices,” she says. “At one of the hospitals they had given people a lot of masks, gloves, and gowns. But then people reported blood on the floor, and they were wearing flip-flops. It’s not just necessarily about the equipment; it is also about training, education, and safe practices beyond using gloves and gowns.”

In contrast to the 2014 Ebola outbreak in West Africa, the current outbreak does not pose a significant threat to the U.S. unless it spreads to areas in Africa with frequent international travel, she says.

“In the West African outbreak in 2014, there was a considerable amount of travel between the United states and Liberia,” Nuzzo says. “That isn’t the case for the DRC and that is possibly why we see the U.S. not doing as much for this outbreak. That is one upside: There are not a lot of international flights to DRC.”

All bets are off if the virus starts spreading to other countries in Africa.

“Once it goes into multiple countries, it is much harder,” she says. “That is really where you feel like there is the potential for it to spiral out of control.”


  1. World Health Organization. Ebola outbreak in the Democratic Republic of the Congo declared a public health emergency of international concern. July 17, 2019. Available at:
  2. Centers for Disease Control and Prevention. Interim guidance for preparing frontline healthcare facilities for patients under investigation (PUIs) for Ebola virus disease (EVD). Available at:
  3. World Health Organization. Ebola Virus Disease. Democratic Republic of the Congo. External Situation Report 51. July 23, 2019. Available at:
  4. BBC. DR Congo Ebola outbreak declared global health emergency. July 17, 2019. Available at:
  5. Henao-Restrepo AM, Longini IM, Egger M, et al. Efficacy and effectiveness of an rVSV-vectored vaccine expressing Ebola surface glycoprotein: Interim results from the Guinea ring vaccination cluster-randomised trial. Lancet 2015;386:857-866.