Another summer, another Ebola outbreak …
On August 1st, 2018 the Ministry of Health in the Democratic Republic of Congo (DRC) reported an outbreak of Ebola virus disease (EVD) in its’ North Kivu province. It is the second outbreak reported in the country this year. Both outbreaks are unrelated and occurred barely two months apart. The response this time has been prompt with the deployment of an experimental vaccine on the ground. A sign that we have learned some tough lessons from the deadly EVD outbreak in W. Africa, which claimed over 11,000 lives.
A chequered journey to success
The current response is laudable but there is a long way to go before we can declare victory. The cost in human life of the EVD outbreak in W. Africa captured global attention and is fresh in our memories. The scale of devastation led to a push for drug and vaccine research against EVD. Reminding us of the pervasive inequities in research funding for diseases that affect the world’s poorest and most vulnerable.
Canadian scientists designed the experimental EVD vaccine rVSV-ZEBOV in 2003. It was shown to be 100% protective in primate models shortly after, in 2005. Funding for clinical trials however stalled for another decade, with the vaccine effectively left on the shelves before moving into human trials in 2014. In hindsight we could have had a tool to prevent what happened in W. Africa, but developing it was not a global health priority until the broader global health community felt threatened by EVD.
The vaccine now produced by MERCK, was used effectively at the end of West Africa’s EVD outbreak in 2016. Over 5000 individuals received the vaccine and none of them developed EVD compared to 23 people in the control group of similar size. These compelling results were too late to change the course of the W. African outbreak. However it provided hope that a future EVD outbreak could be contained in its early stages by timely vaccination.
Following the declaration of the first outbreak in the DRC’s North West city of Mbandaka earlier this year, the government quickly authorized the use of rVSV-EBOV on compassionate grounds. The WHO was greatly criticized for its lack of leadership and sluggish response to the W. African outbreak from 2013-2017. This time it sprung into action partnering with the Global Alliance for Vaccines and Immunization (GAVI) and local health authorities to deliver over 7000 stockpiled doses of the vaccine in a ring vaccination model. Immunizing the immediate contacts — friends, family, housemates, and neighbours — of infected people, to create a protective ring around them and stop transmission.
Effectively implementing the vaccination strategy on the ground is no small feat. The terrain is incredibly difficult with limited transport networks, lack of basic infrastructure to maintain a cold chain, and inherent cultural and linguistic barriers to properly consent the target population. Despite these challenges, 7 weeks after the first case, the outbreak in Mbandaka is effectively contained. This clearly demonstrates that a quick response with the right tools makes a tremendous difference in stopping an outbreak in its tracks. Although this is encouraging, what it means for response preparedness in future outbreaks is more nuanced.
One size does not fit all
Every outbreak is its own separate beast and although we now have a vaccine to combat EVD, its effective use hinges on the unique challenges of where an outbreak occurs. The West Africa outbreak of EVD has been described as the “perfect storm” alluding to the unique challenges in the region that coalesced to create the worst Ebola outbreak in history. In Guinea, Liberia and Sierra Leone, years of civil wars, dysfunctional health care systems, mistrust of the government and western medicine and the ease of movement of populations across porous borders contributed to the devastation of the outbreak. These conditions are similar to those encountered in other countries in the region, also at risk for EVD and other emerging infections.
The DRC knows Ebola too well, a virus named after one of the country’s rivers. The country is on its tenth outbreak in recorded history, most of which have been relatively quickly contained. Previous outbreaks have mostly occurred in remote, inaccessible and rural parts of the country, which helped to limit spread to densely populated major cities. The latest outbreak affecting the North Kivu province is especially scary. North Kivu is at the epicentre of a deadly and protracted civil war and one of the most dangerous parts of the DRC. It is also densely populated with over 8 million inhabitants and shares borders with neighbouring Uganda and Rwanda. There are on-going daily clashes between rival rebel groups, thousands of displaced refugees and near absence of a functional healthcare system.
Even with a vaccine available, we are facing a novel challenge – containing a deadly outbreak of Ebola, where there is war. The coming weeks will be critical as the WHO and the local government grapple with the security concerns for frontline responders, in a race to prevent another humanitarian disaster. With the proximity to international borders, the spectre of the outbreak spreading to other countries in the region is real and should concern us all.
Compassionate preparedness, the way forward
The current scenario in the DRC is not surprising, as interactions between humans and the viral reservoir in endemic regions is a primer for future EVD outbreaks. It was only a matter of time before we saw an outbreak, intersecting with the country’s civil war. The situation the DRC is facing, should send a strong signal that there needs be a more sustained effort to help address systemic issues that make the country and others in the region a especially vulnerable.
We know from previous Ebola outbreaks that it is much more cost-effective for the global community to invest in preparedness than to spend in response. Yet once an outbreak ends the promises for strengthening healthcare systems, improving surveillance and continuing clinical trials for new therapies quickly fade with it. As populations continue to grow and humans encroach on the habitat of zoonotic virus reservoirs, more outbreaks of emerging infections will occur. This year so far Ebola, Human Monkey pox, Lassa and Nipah virus outbreaks have been reported and are on going in parts of Africa and Asia.
Compassionate vaccines and therapies to accelerate response to outbreaks when they occur are welcome but can only be used to their full potential if there are structures and systems in place to deploy them safely. I have no doubt that the DRC will overcome its latest challenge but there will be consequences and a heavy toll to pay if the global community does not rally in support. This support will need to be sustained beyond the present, so we can be truly ready to use the tools we now have, in the future.
Written by Boghuma. K. Titanji
