(CNN) — The ongoing Ebola outbreak in the Democratic Republic of Congo has quickly grown into the second-largest on record, with cases taking just weeks to reach levels that had taken years in previous outbreaks.
There have been at least 3,553 confirmed cases since this outbreak was identified in mid-May, according to data published Friday by the World Health Organization. At least 1,558 people have died.
In just over two months, cases in this outbreak have surpassed the total number reported in another historic Ebola outbreak in the DRC that lasted nearly two years, from August 2018 to June 2020.
The first 1,000 cases in this outbreak were reported within the first 40 days of response activation, according to the US Centers for Disease Control and Prevention, but it took nearly six times as long — about 235 days — to reach more than 1,000 cases during the 2018 outbreak.
Now, the only larger Ebola outbreak is the 2014-16 outbreak in West Africa, which ended with more than 28,600 reported cases and 11,325 deaths.
Challenging circumstances
The current outbreak presents a challenging set of circumstances: it is driven by the rare Bundibugyo strain of the virus, for which vaccines and treatments are not readily available, and active conflict in the region is hindering the ability of response teams to reach affected communities.
“Despite the progress we have made, the outbreak in DRC is continuing to outpace the response,” WHO Director-General Dr. Tedros Adhanom Ghebreyesus said this month. “Intense transmission in the province of Ituri remains our biggest concern.”
About two-thirds of the deaths are happening among people who never received care in a health facility, which can drive community transmission due to exposures that may occur with unsafe handling of bodies.
Each confirmed case in an urban area is believed to have 40 potential contacts; with about 3,400 cases in the DRC, the contact tracing list should have about 135,000 people for outbreak response teams to follow up with.
But only about 1 in 8 — fewer than 18,000 people — have been identified for that list, Dr. Jean Kaseya, director general of the Africa CDC, said at a briefing Thursday. More than 80% of new cases are detected in people who had not been identified through contact tracing.
“If we don’t master this indicator, we’ll not stop this outbreak,” Kaseya said.
“I’m not in a position to tell you that we have total control of this outbreak today, because for me to say that, for me to confirm that we achieved the peak and we can start to think about when, maybe, we can stop this outbreak, we need to ensure that all new cases are coming from the contact list. We need to ensure that all deaths are coming from confirmed cases that we have isolated or admitted,” he said. “This is not the case.”
Of the 3,553 confirmed cases, the vast majority have been reported in the Ituri province in the northeast corner of the country. It is a resource-rich area with lucrative gold mines and trade routes, which drives high population mobility and cross-border movement. It is also home to more than a million displaced people and armed groups, creating widespread insecurity.
Twenty cases associated with the current outbreak have been reported in Uganda and one in France, most of which were imported from the DRC.
On Tuesday, health officials in Uganda declared that the country is “officially Ebola free.”
“The declaration follows the successful completion of all outbreak response measures and confirms that there has been no further transmission of the virus,” according to a release from Uganda’s Ministry of Health.
WHO requires 42 days of enhanced surveillance before the end of an outbreak can be declared, and the organization has not marked this milestone for Uganda.
Research in real time
As the outbreak continues to grow in the DRC, trials for vaccines and treatments are underway.
A vaccine targeting the Bundibugyo strain, developed by the University of Oxford in collaboration with the Serum Institute of India, is the first to reach the clinical trial stage, and the first dose was administered last week. It uses the same technology as the Oxford University/AstraZeneca vaccine for Covid-19.
And a trial of two antiviral therapies – a monoclonal antibody (MBP134) and remdesivir — has been enrolling patients in the DRC for about a month, with at least 41 patients participating so far.
“One of the key lessons from recent outbreaks is that research needs to happen alongside the response, not after it,” Amanda Rojek, associate professor of health emergencies at Oxford’s Pandemic Sciences Institute and operations lead for the trial, said in a statement. “The PARTNERS trial gives us an opportunity to evaluate potential treatments during the outbreak itself, so that the evidence generated can help inform patient care when it is needed most – in months rather than years.”
The 2014-16 outbreak in West Africa — the worst on record — was driven by the Zaire strain of Ebola, which has become the more common strain. But at the time, there were no vaccines or treatments initially available.
Shifting US involvement
The current Ebola outbreak is the “most significant international infectious disease outbreak the Trump administration has had to face in its second term,” according to a KFF analysis — and there are significant differences in how the US government is responding, compared with earlier outbreaks.
The speed of the US government’s response, support of research for countermeasures such as testing, vaccines and treatments, and other funding are on par or surpassing efforts from prior large Ebola outbreaks, the analysis suggests. But there are notable differences in how the US response is structured and “significant upheaval” in US global health programs that “could have implications as the response continues to unfold.”
The US is coordinating with some United Nations agencies but left WHO membership last year, which could “present barriers to communications or coordination at times,” the analysis says.
Past responses were led by the US Agency for International Development (USAID), which was dissolved last year. This role has now shifted to the State Department, but it’s particularly in bureaus that have had recent staff reductions.
“The current relative lack of specified inter-departmental coordination mechanisms could affect the U.S. response over time, particularly if the outbreak is protracted and the U.S. response scales up further,” the analysis said.
There is also a “marked difference” in the US approach to border policies, with certain travelers blocked from entry instead of less restrictive screening and monitoring programs that were used in prior outbreaks.
“The likelihood of Ebola spreading to the United States is considered very low,” according to the US CDC. “If a case was diagnosed in the United States, the risk of Ebola spreading in the United States is also low due to the strength of our public health system and infection control measures.”
The-CNN-Wire
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