Natural Hazards Observer
| January 2007 | Volume XXXI | Number 3 |
Disaster Myths...Second in a Series
Epidemics after Natural Disasters: A Highly Contagious Myth
Most “average, common-sense people-on-the-street” would probably agree that massive epidemics pose a major risk after earthquakes, tidal waves, hurricanes, and other major disasters. And many would consider the presence of dead bodies to be the main cause. To the consternation of seasoned experts, many health responders in the humanitarian community share these mistaken beliefs and perpetuate these misconceptions. Indeed these are among the most persistent and contagious disaster myths that the World Health Organization (WHO) and Pan American Health Organization (PAHO) have tried to eradicate. Sadly, they have had only limited success.
Most myths are based on some degree of truth. Indeed, dead bodies were the reservoir and source of the “Black Death” in Europe in the mid-fourteenth century, and it is also true that longstanding conflicts in failed states that resulted in war-induced famine and the destruction of health services have led to epidemics. Moreover, without doubt, major natural hazards wreak havoc on the environment, often potentially increasing the transmission of water- and vector-borne diseases. However, the likelihood of massive postdisaster epidemics is generally grossly exaggerated. In particular, unburied bodies are incorrectly perceived as a public health threat.
The Risk of Epidemics is Overstated
Unfortunately, some unfounded predictions concerning the threat of epidemics after disasters have originated from “authoritative sources.” For example, after 2004’s Hurricane Jeanne in Haiti (in which 3000 died), a warning of a possible cholera epidemic was issued, although cholera had not been present in Haiti for decades. Other statements from supposed authorities have included: “Over 10,000 may die from shigellosis outbreaks following the Nicaragua earthquake,”1 and “We could have as many dying from communicable diseases as from the tsunami.”2 In fact, almost every disaster—whether in a developed or developing country—has resulted in similarly alarming statements from health “experts.” Of course, these statements immediately found their way into the mass media.
However, in each case increased disease surveillance failed to identify any unusual outbreak, a fact the media often overlooked in favor of more sensational headlines. Paradoxically, random surveys that followed large-scale disasters such as the 1970 tidal wave in Bangladesh (in which 250,000 to 400,000 deaths occurred) suggested that the public health status of the surviving population was “better than that of the non-affected population.” This may be explained by another survey finding that “those too young, too old, and too weak to hold on to the trees” were lost in the storm.3 The same mortality pattern was observed in the 2004 Indian Ocean tsunami, but no comparative health survey was carried out in spite of the abundance of resources mobilized for epidemiological study and control.
Such findings should not be construed to show that there is no risk of increased disease transmission after a disaster. Overcrowding, poor sanitation, or contaminated water definitely can contribute to public health problems. What must be determined is the degree to which public health deterioration is attributable to the disaster. In poor countries where unsanitary conditions often are the norm, disaster-induced deterioration of public health may be minimal and quickly reversed or even improved by humanitarian assistance. Somewhat ironically, developed countries have much more to lose, given their initially higher health standards, but greater awareness and resources in those countries usually compensates, or even overcompensates, for any adverse changes in public health.
Dead Bodies are not a Public Health Hazard
Associating epidemics with the presence of human remains after an accident, conflict, or disaster is a deeply ingrained myth in Western culture. Cholera, typhoid fever, typhus, smallpox, and other diseases are caused by specific pathogens for which a decaying body is not a particularly favorable environment. If the causal agent was ever present—a rare occurrence in a normally healthy population—the micro-organisms quickly cease to proliferate and progressively die off in cadavers. In other words, a human carrier of any disease is less of a hazard dead than alive. Except for the risk of directly contaminating water, dead bodies pose no credible public health risk for the general population. It is even less rational to alarm an already traumatized population when bodies have been buried by landslides or earthquakes.
When Disaster Myths Get in the Way of Planning and Response
Using scaremonger tactics to promote public health is counterproductive. Such an approach damages the credibility of relief agencies and diverts resources away from real priorities. Adopting proper public health measures requires cooperation from the public and the support of funding agencies. Such cooperation is based on trust and credibility, and ultimately, exaggerated warnings can only undermine that trust. Such warnings can prompt authorities to overact and employ extraordinary measures to control the “risk.” For example, massive spraying to control disease vectors can become a substitute for proper solid waste disposal. Improvised, unneeded mass vaccination campaigns against diseases that are not locally present can become a political necessity, as occurred with cholera immunization in Aceh Province, Indonesia, after the 2004 tsunami. Besides being an unnecessary expenditure of time, money, and human resources, these immunization campaigns can be a significant inconvenience for a population already under considerable stress.
The more visible and expensive the response measures employed, the greater the false sense of security they induce. The resources mistakenly allocated for these measures could be better used to strengthen routine public health programs, improve water and sanitation, or support the recovery process. Indeed, as with consequence management in terrorism events, the most effective use of resources is to strengthen the capacity of the local health services before any emergency.
Treating dead bodies as a public heath threat affects the population more directly. Mass burials or cremations unnecessarily heighten the drama of a disaster and have potentially serious mental, social, and legal consequences. In all cultures, the process of identifying the dead and conducting a ritual burial is an essential part of the grieving process (witness, for example, the effort and money spent by the United States to identify human remains decades after the Vietnam War). Proper handling of cadavers reflects the real need of affected families to respect and honor their lost relatives. Summarily disposing of bodies in mass graves violates the human rights of the survivors.
Further, the legal and financial complications related to a missing person also have considerable implications for the welfare and subsistence of family members. Since the 2004 tsunami, national authorities in Sri Lanka and Thailand have become much more aware of the importance of proper identification and handling of human remains. Unfortunately, the mass media and unknowledgeable responders help to keep alive the myth of the need for speedy burial.
Current Research
The overwhelming magnitude of the problem of human remains after the 2004 tsunami and the unusual sight of dead bodies in the streets of New Orleans has resulted in several studies and publications—from PAHO guidelines4 to editorials in disaster journals5 to systematic reviews of past disasters.
Lacking thorough research, little is actually known about the survival of human pathogens in the deceased. Even if active multiplication stops rapidly, how long the pathogens can survive is still matter of scientific guesswork. Sample-based surveys with control groups (unaffected populations) could be used to assess the risk of epidemics according each type of disaster. It is regrettable that WHO did not see the need for such studies after recent disasters (even though other follow-up studies were well funded). Such studies should be planned now in advance of the next major disaster.
Why so Little Progress, and Where Do We Go from Here?
In the last several years a number of publications and articles have been issued regarding this problem. Yet the issue is not so much one of research but of adoption of the conclusions and recommendations of existing research, the timely subject of the first entry in this Disaster Myths series, which appeared in the September issue of the Observer. Disagreement, when there is any, tends to be not scientific but emotional – accepting the realities rather than the myth goes against what we have believed for centuries.
There are, however, some troubling outcomes that can reinforce these myths. Doomsday predictions, when disseminated by the mass media, do pay off in the short term. It’s a win-win situation. When an outbreak does not materialize, credit goes to the effectiveness of health agencies and the extreme measures taken. When the number of reported cases of a disease does increase (whether or not the increase is attributable to the disaster or to better surveillance), the need for more resources is confirmed.
Repudiating this disaster myth may ruin the reputation of an expert or decision maker brave enough to try to calm the public and dispel a longstanding misconception. Hence, many national or international experts privately disagreed with the alarmist predictions made in the wake of Hurricane Katrina, the 2004 tsunami, or the recent earthquakes in Asia, but publicly remained silent. At the same time, there does seem to be an encouraging increase in responsible reporting by the media in more recent disasters—for example after the recent Philippines mudslide and Indonesian earthquake.
How can we move ahead? The debate about these issues must be broadened in the scientific and disaster communities. More editorials, research, and publications are needed. But above all, the public must be increasingly involved and made aware through the mass media. The launching of a public education campaign associated with the proactive release of scientifically sound statements in the immediate aftermath of disasters may force the issue onto the front page of responsible publications and prevent the spread of alarmist statements. Educating the public is costly but indispensable.
Claude de Ville de Goyet (cdevill@attglobal.net)
Consultant on Risk Management and Former Director, Emergency Preparedness Program,
Pan American Health Organization
Resources
(1) Vijil, C. 1973. Letter to the Editor. Lancet 1: 146.
(2) Dr. David Nabarro, head of crisis operations for the World Health Organization, quoted in “Anticipating Wave of Disease.” CBS News and Associated Press, December 29, 2004. www.cbsnews.com/stories/2004/12/28/world/main663462.shtml
(3) A. Sommer and W.H. Mosley. 1973. “The Cyclone: Medical Assessment and Determination of Relief and Rehabilitation Needs.” p.125 in Lincoln C. Chen, editor, Disaster in Bangladesh – Health Crises in a Developing Nation. London: Oxford University Press.
(4) Pan American Health Organization. 2004. Management of Dead Bodies after Disasters: A Field Manual for First Responders. Washington, D.C.: PAHO and World Health Organization. 194 pp. www.paho.org/english/dd/ped/ManejoCadaveres.htm
(5) See, for example, the forthcoming editorial in the Journal of Prehospital and Disaster Medicine, January-February 2007 issue.