Abstract
Outbreaks of the filoviruses, Ebola and Marburg, usually garner immense public attention, often with a sensationalist bent in the lay press, focused on the apparently mysterious origins of the outbreak and the high mortality rates. The scientific community may present a more objective viewpoint, but usually with a rather technical focus on identifying epidemiological risk factors and experimental therapies and vaccines. Often lost in the discussion are the human rights elements that consistently underlie large outbreaks of these dangerous viruses.
Keywords: Ebola, Marburg, viral hemorrhagic fever, human rights
“The biggest problems at Donka are no electricity, no water, no equipment, no sanitation, and very high rates of infection.”
Bintu Cissé, adjunct midwife supervisor at Donka National Hospital in Conakry, Guinea, site of an outbreak of Ebola virus disease with nosocomial transmission [1].
THE POPULAR VERSION
The filoviruses, Ebola and Marburg, cause occasional outbreaks in sub-Saharan Africa, with case-fatality ratios routinely >50%. The major and tragic outbreak of Ebola virus disease that started in 2013 with its epicenter in the impoverished nation of Guinea has once again thrust this disease into the limelight [2]. Ebola virus outbreaks have held a special public fascination since the mid-1990s. A deadly virus mysteriously emerges from the remote jungles of sub-Saharan Africa, wreaking unspeakable havoc on nearby villagers, and then just as mysteriously recedes from whence it came. Unknowingly, an unlucky traveler in the area is also infected, incubating the virus as he completes his travels and arrives home to a major metropolitan area. Suddenly, fever sets in, and within days the man is deathly ill, bleeding from the eyes, his internal organs liquefying. His disease quickly spreads to all those in proximity. Case numbers mount rapidly. Chaos ensues, overwhelming the local healthcare system. Fears that the event is a bioterrorist attack rattle the population. Such is the notion of Ebola virus garnered from popular accounts, such as Richard Preston's best-selling novel The Hot Zone and the 1995 film Outbreak. Although such scenarios may still sell movies, accumulating scientific knowledge and experience debunk much of this popular notion.
THE SCIENTIFIC VERSION
Science has, in a sense, benefitted from the public fascination and fear; the recent economic downturn aside, funding for Ebola virus and other real or perceived bioterrorist agents has increased dramatically in recent decades, as have related publications [3, 4]. Although they are obviously very dangerous, it is now clear that Ebola and Marburg viruses are far less transmissible than first feared, requiring direct contact with blood and bodily fluids during the period of acute illness. The risk of significant secondary transmission from imported cases into industrialized countries, where protective materials and clean needles are routinely available and used, is low. Natural transmission through aerosol seems to be rare, if it occurs at all. Both field and laboratory research have shed light on the epidemiology of these viruses, which are all zoonotic. Bats seem to be the reservoir for the filoviruses, and seasonal fluctuations in bat breeding populations and proportions of infected animals may influence risk of transmission to humans [5–7]. Numerous experimental vaccines have demonstrated efficacy in animal models and have recently been accelerated into clinical trials in humans [8, 9].
THE HUMAN RIGHTS VERSION
There are still mysteries to be solved and scientific advances to be made regarding the filoviruses, especially with regard to viral pathogenesis and treatment options. Nevertheless, the factors dictating the location of large filovirus outbreaks have been empirically clear for decades, if understated, and are inevitably intertwined with the sociopolitical landscape. Such outbreaks almost invariable occur in areas where the public health system has been decimated from years of civil conflict or failed development (Table 1) [3, 10–13]. Biological and ecological factors may drive emergence of these viruses from the jungle, but clearly the sociopolitical landscape dictates whether they are then confined to a few isolated cases or explode into a major outbreak.
Table 1.
Laboratory-Confirmed Outbreaks of Ebola and Marburg Virus Disease Since Discovery Through June 2015a
Year of Onset | Virus | Country | Epicenter(s) | Cases, No. (CFR, %) | Source of Primary Infection | Factors Contributing to Secondary Spread | Underlying Civil Unrest in Country or Region? | Country UNDP HDI Rankingb |
---|---|---|---|---|---|---|---|---|
1967 | Marburg | Germany and Yugoslavia | Marburg and Cologne, Germany; Belgrade, Yugoslavia | 32 (22) | Imported monkeys from Uganda | Dissection of monkeys to harvest organs, Nosocomial transmission | No | Germany, 5; Yugoslavia, 64 |
1975 | Marburg | Rhodesia (present-day Zimbabwe) and South Africa | Travelers; exact site of infection unknown | 3 (33) | Unknown | Nosocomial transmission | No | Rhodesia, 172; South Africa, 121 |
1976 | Ebola | Zaire (present-day DRC) | Yambuku | 318 (88) | Unknown | Nosocomial transmission | Aftermath of DRC independence crisis (1960–1965); Mobutu “kleptocracy” and failed state (1965–1997) | 186 |
1976 | Ebola | Sudan | Maridi and Nzara | 284 (53) | Unknown | Nosocomial transmission | First Sudan civil war (1955–1972) | 171 |
1979 | Ebola | Sudan | Maridi and Nzara | 34 (65) | Unknown | Nosocomial transmission | First Sudan civil war (1955–1972) | 171 |
1980 | Marburg | Kenya | Kisumu | 2 (50) | Cave entry | Nosocomial transmission | No | 145 |
1994 | Ebola | Gabon | Mékouka, Ogooué-Ivindo Province | 52 (60) | Infection in gold mining camps | Traditional healing practices; nosocomial and community-based transmission | No | 106 |
1995 | Ebola | DRC | Kikwit | 315 (81) | Unknown | Nosocomial and community-based transmission | Mobutu kleptocracy and failed state (1965–1997) | 186 |
1996 | Ebola | Gabon | Mayibout, Ogooué-Ivindo Province | 21 (57) | Consumption of dead chimpanzee | Community-based transmission | No | 106 |
1996 | Ebola | Gabon | Booué, Ogooué-Ivindo Province | 45 (74) | Consumption of chimpanzee? | Nosocomial and community-based transmission | No | 106 |
1996 | Ebola | South Africa | Johannesburg | 2 (50) | Imported from Gabon by infected physician | Nosocomial transmission | No | 121 |
1998 | Marburg | DRC | Durba | 154 (83) | Repeated primary introductions from exposure in gold mine | Community-based transmission | Second DRC civil war (1996–1997); Mobutu kleptocracy and failed state (1965–1997) | 186 |
2000 | Ebola | Uganda | Gulu | 425 (53) | Unknown | Nosocomial and community-based transmission | Lord's Resistance Army insurgency, 1987 to present | 161 |
2001 | Ebola | Gabon and ROC | Ogooué-Ivindo Province, Gabon; Cuvette Ouest Region, ROC | 65 (82) | Hunting and consumption of nonhuman primates | Nosocomial transmission and community-based transmission; traditional healing practices | ROC civil war (1997–1999) | Gabon, 106; ROC, 142 |
2001 | Ebola | Gabon and ROC | Ogooué-Ivindo Province; Cuvette Ouest Region | 57 (75) | Unknown | Community-based transmission | ROC civil war (1997–1999) | Gabon, 106; ROC, 142 |
2002 | Ebola | ROC | Mbomo and Kéllé, Cuvette Ouest Region | 143 (89) | Hunting and consumption of nonhuman primates | Nosocomial and community-based transmission, Traditional healing practices | ROC civil war (1997–1999) | 142 |
2003 | Ebola | ROC | Mbomo and Mbandza, Cuvette Ouest Region | 35 (83) | Hunting and consumption of nonhuman primates | Traditional healing practices | ROC civil war (1997–1999) | 142 |
2004 | Marburg | Angola | Uíge | 252 (90) | Unknown | Nosocomial transmission and community-based transmission | War of independence (1961–1974) and civil war (1975–2002) | 148 |
2004 | Ebola | South Sudan | Yambio | 17 (41) | Exposure to baboon meat? | Nosocomial transmission and community-based transmission | Second Sudan civil war (1983–2005) | 171 |
2007 | Marburg | Uganda | Ibanda, Kamwenge | 4 (25) | Bat exposure in gold mine | Community-based transmission | No | 161 |
2007 | Ebola | DRC | Kasai Occidental Province | 264 (71) | Exposure to local wildlife, including bats | Nosocomial and community-based transmission | Ongoing armed conflict | 186 |
2007 | Ebola | Uganda | Bundibugyo | 149 (25) | Unknown | Nocosomial transmission and community-based transmission | No | 161 |
2007 | Ebola | DRC | Mweka and Luebo | 32 (47) | Exposure to fruit bats through hunting? | Unknown | Ongoing armed conflict | 186 |
2012 | Marburg | Uganda | Kimbale, Ibanda, Kamwange | 41 (58) | Unknown | Community-based transmission | No | 161 |
2012 | Ebola | Uganda | Kibaale | 11 (36) | Unknown | Community-based transmission | No | 161 |
2012 | Ebola | DRC | Province Orientale | 36 (36) | Hunted bushmeat? | Community-based transmission | Ongoing armed conflict | 186 |
2012 | Ebola | Uganda | Luwero | 6 (50) | Unknown | Unknown | No | 161 |
2013 | Ebola | Republic of Guinea, Liberia, and Sierra Leone | Southeast forest region of Guinea | Ongoing; >27 500 cases at this writing | Unknown | Nosocomial and community-based transmission | Guinea: long-standing civil unrest and tribal conflict, coup d’état (2009); Liberia: civil wars (1989–1996 and 1999–2003); Sierra Leone: civil war (1991–2002) | Guinea, 178; Liberia, 174; Sierra Leone, 177 |
2014 | Ebola | DRC | Province Equateur | 66 (74) | Hunted bushmeat? | Community-based transmission | Ongoing armed conflict | 186 |
Abbreviations: CFR, case fatality rate; DRC, Democratic Republic of the Congo; ROC, Republic of the Congo; UNDP HDI, United Nations Development Programme Human Development Index.
a Single cases and cases related to laboratory infections are not shown.
b Of 187 ranked countries, 2013 rankings [14]. The median ranking for countries with a recognized Ebola or Marburg virus outbreak is 154.5.
This process represents, in part, the unfortunate and unintended result of the incorporation of “Western medicine” into the “traditional medicine” backdrop of sub-Saharan Africa over the past century, followed in some places by years of stalled development, as in Guinea, Liberia, and Sierra Leone. These 3 countries are all presently ranked near the bottom of the 187 nations on the United Nations Development Programme Human Development Index [14], with a majority of their populations living below the national poverty lines. Colonial powers and missionaries, followed later by African governments and nongovernmental organizations, began establishing clinics and hospitals for persons in need in remote and impoverished areas. Walls and roofs were built, a few physicians or nurses employed, and a basic stock of medicines and supplies provided.
Years later, worn down by war and civil unrest, the walls may still exist and a tenacious healthcare worker may be hanging on, eking out a living in an informal fee-for-service small-scale economy, but the formal supply chain is long gone, including a reliable supply of clean needles and gloves. Consequently, when a patient with filovirus infection, presumably representing one of the early infections from a zoonotic source, presents to one of these centers, the likelihood of hospital-based transmission is high. Having few options, the healthcare worker may reuse the needle just used to administer an injection to the patient with (unrecognized) Ebola virus disease for the patient with malaria in the next bed, who subsequently leaves the hospital cured of malaria but incubating Ebola virus. This person then falls ill at home, infecting a few family members in the process, who then come to the hospital, renewing the cycle of hospital-based transmission and delivery to the community. The absence of gloves and other personal protective equipment also puts healthcare workers at risk; indeed, many filovirus outbreaks are first detected by noting clusters of infection and deaths among healthcare workers. Thus, filovirus outbreaks can be considered fundamental problems related to a lack of a basic human right—the right to health, defined in the United Nations Declaration of Human Rights as “a standard of living adequate for the health and well-being of himself and of his family, including food, clothing, housing and medical care.” [15].
Of course, filoviruses are not the only diseases to which the populations of struggling nations and healthcare systems are rendered vulnerable. A common criticism in the field of filoviruses and emerging viruses is “Why waste time and money on this exotic esoterica while millions of persons suffer daily from AIDS and malaria?” Indeed, despite the large outbreak in West Africa, Ebola and filoviruses remain low on the problem list for most of the world's population, including most persons living in sub-Saharan Africa. Nevertheless, filoviruses can be considered the proverbial “canaries in the coal mine,” indicators of some of the world's most vulnerable communities, not only for filoviruses, but for a host of other infectious and noninfectious diseases, for poverty-related conditions, for mental and physical trauma due to civil strife, for environmental degradation, in populations whose basic human rights are routinely not respected and distinctly in jeopardy.
STEPS FORWARD
One key step in confronting filoviruses and other emerging diseases is building capacity on the front lines where diseases emerge, primarily at the zoonotic interface in the developing world [16]. Much more than simply building a laboratory in a developing country, this entails stemming the “brain drain” through the training and provision of home-country research and public health career opportunities for developing world scientists, exploring novel and technology-appropriate approaches to local problems, and advocating for funding mechanisms that enable their execution. Long after the Ebola virus outbreak in West Africa is contained, these will be our true measures of success and capacity to prevent future outbreaks.
Although no one should advocate a major displacement of funds from global and pandemic diseases such as AIDS, tuberculosis, and influenza, we nevertheless must keep one eye out for what might come next. How different might the scourge of AIDS be today if we had had the capacity to detect the virus when it first emerged in sub-Saharan Africa in the early 20th century? How much worse would the 2003 severe acute respiratory syndrome–coronavirus pandemic (which resulted in only about 8000 infections worldwide—0.0001% of the global population) have been had we not been able to discover and fully sequence the virus, develop first-generation diagnostic assays, and implement global infection control measures, all within a few months after the disease first came to international recognition? In the case of Guinea, with no access to such modern biomedical means or communications systems, Ebola virus circulated undetected for at least 3 months, causing 111 cases and 79 deaths, quietly slipping into neighboring Liberia and Sierra Leone [2].
Second, we must not forget the all-important sociopolitical component of filoviruses and so many other diseases, which even the most advanced scientific technology cannot solve. Health science training in the United States has often presents a false dichotomy that implies that one is either a “science type” or a “human rights type,” either a future “virus hunter” or an “activist.” As it turns out, if we truly want to make a difference in people's health, we need to pursue social justice as avidly as we do virology.
Finally, the question we must ask—no, demand—of health science, is “So what?” After all, health science should not be an entity unto itself, but rather a means to an end, primarily about, well, health. In the United States and Europe our fears of filovirus-related bioterrorism and imported infections have driven considerable research investment, with, for example, the development of numerous promising Ebola virus candidate vaccines and prophylactics. Although the unprecedented acceleration in clinical trials of therapeutics and vaccines for Ebola virus disease has been most welcome, these products still face significant hurdles if they are to be translated into tangible measures to improve and protect health, for both persons concerned about bioterrorism and those at risk of natural transmission in endemic areas. Advocacy is needed to move this process forward, for Ebola virus and many other emerging diseases, especially to make sure that the benefits indeed “trickle down” to those most in need in sub-Saharan Africa, hopefully without necessitating a major humanitarian crisis to make it happen.
Notes
Acknowledgments. We thank Frederique Jacquerioz and Erik Reaves for creative input to this article and Lara Schwarz for assistance with the table.
Potential conflict of interest. Both authors: No reported conflicts.
Both authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
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