Author(s): Carlos Castillejos, M.D., is the global head of medical and scientific affairs for global public health at Johnson & Johnson
For the third year in a row, Marburg virus has appeared in Africa, with Equatorial Guinea reporting cases and Tanzania confirming its first-ever outbreak.
The reoccurrence of Marburg is not isolated. In fact, outbreaks of deadly filoviruses that cause fatal hemorrhagic fevers are increasing. Marburg is related to the more common Ebola virus, and specifically the Zaire ebolavirus, which has appeared nearly annually since 2000 and is responsible for the deadliest filovirus outbreaks on record: the 2014-2016 crisis in West Africa and the 2018-2020 outbreak in the Democratic Republic of the Congo (DRC). More than 32,000 people acquired Ebola during these outbreaks, crippling entire communities and causing more than 13,000 deaths.
Ebola outbreaks can be devastating. And too often, it’s the frontline health workers who are consistently at the greatest risk for exposure, sickness and death, with significant implications for the resilience of entire health systems.
The traditional response to Ebola outbreaks – quarantining, contact tracing and, more recently, the introduction of ring vaccination – has been inherently reactive. The Africa Centres for Disease Control and Prevention (CDC) recently ranked Ebola among the diseases with the highest risk trajectory, epidemic potential and severity, and current tactics may not be sufficient.
A more comprehensive approach may help. Multiple Zaire ebolavirus vaccines have been licensed, and potentially more are on the way for Sudan ebolavirus, a similar but distinct virus that recently erupted in Uganda. Current ring vaccination strategies play an important role but mean that jabs begin only after people sicken. Including proactive vaccination is key to protecting frontline health workers and strengthening health systems in the face of both Ebola and future threats.
There are clear factors driving increased outbreaks. Until recently, human cases of Ebola were believed to be “spillover” events, with the virus jumping from animal to person. However, the discovery that Ebola can persist in the bodily fluids of some survivors, only to re-emerge years later, is challenging this assumption. Given this, the continued re-emergence of Ebola more closely resembles regular flare-ups of an endemic disease, not isolated events.
The risk of spillovers may also be increasing. Africa has reported a significant uptick in zoonotic diseases over the past decade, while human encroachment on wildlife and accelerating climate change both contribute to environments that are more favorable for Ebola. Furthermore, increased urbanization and connectivity mean that trips from relatively remote villages to well-connected cities are now much easier.
While Ebola outbreaks have often occurred in sparsely populated areas, the recent Sudan ebolavirus outbreak in Uganda affected the capital city of Kampala, which sits at the center of a metro area of more than three million people. Experience from the 2014 and 2018 Zaire ebolavirus outbreaks in West Africa and the DRC shows that the current Ebola response protocol of quarantines, lockdowns and ring vaccinations is extremely difficult to execute in urban environments where conditions are favorable for transmission.
Regardless of setting, more frequent outbreaks level a deadly burden on frontline health workers, putting them at disproportionate risk. In 2014 in Sierra Leone, healthcare workers were 21-32 times more likely to acquire Ebola than the general adult population; more than 220 died.
The incapacitation and death of frontline health care workers is tragic. It can also have devastating impacts on entire health systems, especially in resource-limited settings where workers are already stretched thin. Health systems become less able to meet the routine medical needs of the people they serve, and are not able to respond to other health threats like filoviruses, coronaviruses and more.
There’s clearly a need to protect vulnerable people, communities and frontline health workers as outbreaks become more common and the success of the Rwandan government’s collaborative UMURINZI campaign, which vaccinated more than 200,000 people over a multi-year period and worked closely with the communities involved, shows that large-scale, proactive vaccination campaigns are viable.
While vaccines protecting against Zaire ebolavirus are available, explicit guidelines to help support a more comprehensive prevention strategy need to be developed. Stakeholders at every level should invest in and prioritize assisting communities and health workers facing Ebola, including by updating more common response protocols to include a proactive approach towards healthcare workers. In addition to helping address Ebola, doing so will strengthen the health systems needed to provide primary care and respond to other healthcare threats.
By more thoroughly deploying the cutting-edge tools that were developed following the 2014 outbreak, we can not only help prevent more deaths from this virus, but also protect frontline health workers as the backbone of strong, resilient health systems.
As the increasing pace of outbreaks makes clear, lives are at stake. We must invest in eliminating the risk of the pandemic threats that are right here in front of us and within our reach, as well as prepare for unknown threats.