The size and scale of the 2014-16 West African Ebola epidemic sent shockwaves throughout the world. In late summer 2014, television screens beamed disturbing images of people dying in the streets and desperate health workers pleading for more help. Yet the outbreak had been discovered six months before with little to no media attention and warnings of its unprecedented nature ignored. So how did it spiral so far out of control?
This outbreak exposed how collectively vulnerable and ill-prepared we are to cope with a deadly infectious disease which quickly crosses borders. Yet the failure to respond to epidemics is not new and did not appear only when Ebola struck west Africa. Everyday outbreaks of less exotic diseases like measles, cholera, and malaria continue to claim an intolerable number of lives every year.
Infectious diseases with epidemic potential cause the most deaths worldwide for children between the ages of one to five years every year. In Africa, the sub-Saharan region has the highest child mortality rates, with the majority of these deaths related to vaccine-preventable and infectious diseases. No single, real-time global database exists to gauge the true extent of the problem of epidemics.
The shock of the Ebola epidemic justifiably provoked a global debate on the power of disease outbreaks and the limitations of the health and aid systems designed to respond to them. No less than four panels of experts convened in its aftermath to examine what went wrong and proffer suggestions for future improvements. All observed that reform is sorely required to address three key problem areas: weak national health systems, poor global health governance, and inequitable and deficient R&D for neglected diseases.
The need to act on these reforms is undisputed, not least because the need to tackle the next outbreak in Africa has already materialised. A significant yellow fever outbreak is threatening central Africa after cases of the incurable infectious disease appeared in Angola’s capital city, Luanda, in December 2015. It has since spread to all provinces across the country, then on to neighbouring Democratic Republic of Congo (DRC), where it now menaces the DRC capital Kinshasa, a city of 10 million people.
The United Nations High-Level panel convened to review the Ebola epidemic described it as ‘a preventable tragedy’. Will yellow fever follow a similar path in central Africa?
Lessons from Ebola
For the first three months, the Ebola virus spread undetected due to a lack of basic surveillance capacity in the overstretched, understaffed health systems of Guinea, Liberia and Sierra Leone, which were already struggling to meet the needs of their people. Once recognised, the scale of the outbreak was minimised by the national authorities and the World Health Organization (WHO), which maintained that the outbreak would be soon under control.
Viral haemorrhagic fever experts from the medical humanitarian organization I work with, Médecins Sans Frontières (MSF), deployed at the onset in March 2014, were immediately alarmed by the geographic spread of the cases. Past outbreaks typically took place in remote areas, where they were easier to contain. This time the diffusion of small numbers of cases over a wide geographical area multiplied the staff, logistics and laboratory capacity needed in each location to bring the virus under control.
A week after the discovery of the outbreak, MSF issued a public statement warning of the unprecedented rapid spread of the disease. In June, the organization publicly declared the outbreak out of control after observing that the virus was actively transmitting in more than 60 locations in Guinea, Liberia and Sierra Leone. Nevertheless, for the first six months of the outbreak, national health workers and MSF teams bore the bulk of care for Ebola patients.
It was not until 1,600 people had been infected, and possibly because realisation dawned that Ebola could cross the ocean via air passengers and threaten wealthy countries in the west, that the WHO declared the Ebola outbreak to be a Public Health Emergency of International Concern (PHEIC). Thus the world’s attention was garnered, marshalling unprecedented international resources, including the deployment of foreign military assets. The African Union mobilised human resources among its member states, resulting in a unique deployment of hundreds of African healthcare workers.
Despite representing the largest international response to an epidemic in history, the outbreak still cost more than 11,000 people their lives before it was controlled. Had the outbreak been detected faster and had international action been more quickly mounted in the face of a rapidly spreading incurable virus, thousands could have been saved.
Political leadership, will and accountability – the keys to success
The response of Nigeria, Senegal and Mali when Ebola spilled over to their shores demonstrated how strong political action can avert the acceleration of an epidemic. Fear struck the hearts of many when Ebola first arrived via an air passenger in Lagos, Nigeria, a city of 20 million people. But the government’s quick decisive action, including deploying significant human and financial resources, implementing rigorous control measures, repurposing polio infrastructure, and conducting high-quality epidemiology, were all critical to preventing a widespread epidemic.
Prioritising emergency response and the power of collective effort
Many are quick to blame weak health systems for the Ebola epidemic’s explosion and prescribe the solution of health systems strengthening. While investing in long-term programmes to strengthen health systems is surely laudable and necessary, prevention measures will not always mitigate disease outbreaks. Therefore, building and maintaining emergency responses must also be prioritised and sufficient resources put in place to react swiftly and flexibly.
Countries should also be able to count on international solidarity and practical assistance when facing health emergencies. Requesting external assistance should not be seen as a failure, but rather rewarded as a measure of political courage. In a highly connected world where diseases know no borders, fostering collective effort against epidemics should be regarded as a natural response from states.
Failure of the R&D agendas for neglected diseases
Despite 24 outbreaks over the past 40 years, there was still no safe and effective vaccine, drug, or rapid diagnostic test on the market against Ebola in humans when the outbreak began. The virus was never considered a priority for pharmaceutical companies, as it affected only a small number of impoverished patients in short-lived, remote outbreaks in Africa.
The availability of a proven vaccine marks a clear distinction between the Ebola epidemic and the current yellow fever outbreak in Angola and DRC. In theory, no one should be dying of yellow fever today. Though it has no cure or rapid diagnostic test, a highly effective and cheap yellow fever vaccine has been available for the past 80 years, and a single dose provides lifetime immunity. So why the sudden surge and international spread of cases?
Here the similarities in the two outbreaks are key: urbanisation, high population mobility, no rapid tests and limited laboratory capacity. The spread of Ebola in Guinea’s capital, Conakry, is thought to be the first instance of widespread transmission of the virus in an urban area. Similarly, yellow fever emerged in the capital city of Luanda. The short delay in recognising the disease, coupled with the inability to quickly diagnose cases and then reactively vaccinate, allowed it to take hold in the city and spread nationally while the vaccination campaign lagged behind. A rapid diagnostic test for both diseases would truly be a game-changer in speeding up response, but in both cases the failure of the R&D system prevents this.
Halting the yellow fever outbreak in central Africa
A bigger problem looms on the horizon. The supply of the yellow fever vaccine is limited. The global stockpile has been already depleted twice, partly due to the large-scale vaccination of Luanda that used up the vaccine. Efforts are being made to replenish the global stockpile, but the concern is that if the outbreak is not brought under control and ignites in other large urban settings, the global supplies will be depleted. All efforts must continue to halt its further spread before it becomes an uncontrollable outbreak. Neighbouring countries equally must remain vigilant.
A mass vaccination campaign is in the works for Kinshasa in the coming weeks. The global health community waits with bated breath to see if these efforts will halt another preventable tragedy.