Following the devastating impact of the tsunamis in South Asia, public health officials are now worried about the emergence of epidemics. In its latest update, the World Health Organisation warns that millions of people are under "serious threat" of disease outbreaks. Dengue fever, malaria, typhoid, cholera and other water-borne diseases could cause as many casualties as the unforgiving waves of the Indian Ocean.
Even a cursory glance at medical history shows that epidemics have killed far greater numbers than natural disasters. The flu pandemic of 1918 alone caused the deaths of an estimated 20 million people. So can history help us to understand and control outbreaks of disease?
Humans and disease have always co-existed. The world's most isolated communities, from Africa to Papua New Guinea, developed ways to contain the most virulent of epidemics. The native inhabitants of early 20th-century Belgian Congo lived amid malaria, leprosy, river blindness and a plethora of other infections. Sleeping sickness, later unleashed by the ecological disruption of European colonisers, was kept under check by a variety of preventive indigenous mechanisms.
Yet, when epidemics occur, the social impact can extend beyond individuals to entire communities. The fear and stigma associated with certain diseases can alter the behaviour of a whole population. In the town of Mbarara, during the 2000 Ugandan outbreak of Ebola - an acute viral disease with lethality rates approaching 90 per cent - inhabitants refused to shake hands or handle notes and coins, and wore latex gloves to prevent infection.
The extent and intensity of the stigma can be such that epidemiologists have referred to the phenomenon as a "second epidemic". Reducing social stigma through a clear explanation of the disease to local communities should be a priority in the effort to control the impact of epidemics.
Fear is a common characteristic of severe epidemics. For obvious reasons, hospitals were shunned by most people. Flight from the hospital, by both patients and hospital staff, is recurrent in many outbreaks of virulent disease.
In the 1995 Ebola epidemic in Kikwit, the majority of patients and health workers deserted the hospital and only moribund patients and voluntary workers remained. Tom Ksiazek, of the Centers for Disease Control (CDC), visited the abandoned hospital and found 30 expiring patients, left to care for themselves amid rotting corpses, sometimes in the same bed.
A historical analysis of past epidemics reveals the dangers of ignoring local customs. Maryinez Lyons, a medical historian, has described how colonisers neglected African customs during the sleeping sickness epidemic that ravaged the Belgian Congo, and the hazardous effects of this cultural disdain.
For the afflicted Africans, the invasive colonisers prevented their movement, touched and inspected their bodies in unfamiliar ways, forced them to take certain drugs whose efficacy they doubted and sent their loved ones to lazarettos from which they would seldom return. As a result, many villagers hid during the much-feared doctors' visits, patients in the lazarettos regularly fled and, in two cases, revolts occurred.
In many Ebola outbreaks, bodies were buried before family members could identify the corpse. As a consequence, families hid their sick and refused to send them to hospital. Rumours of Europeans selling body parts for profit proliferated. In South Asia today, many bodies are buried en masse, amid ill-placed fears that corpses always trigger epidemics.
The WHO has stressed that survivors pose a much greater risk of infection than cadavers, as most infectious agents cannot live long in a corpse. Few consider the psychological effects that burying the dead in mass graves will have on still-hopeful or grieving relatives.
Whereas, in colonial times, the medical staff involved in the control of epidemics were often based on site and, as a result of longer stays, became more aware of indigenous beliefs and practices, much of the help today comes from abroad. Scientists from the disease control centres, for instance, are often sent on assignment at short notice and with little knowledge of the cultural context of the epidemics.
The closure of old training bases has affected the number of suitably trained scientists. There is at present a "vacuum of young researchers truly versed in the study of tropical pathogens", according to Dan Bausch, an epidemiologist at the CDC.
Despite some differences, most severe epidemics of infectious disease share a set of common features. Fear, flight and stigmatisation appear time and time again in past epidemics across the globe. A knowledge of the anatomy of past epidemics, of the success stories and disasters, can reveal insights that can help us deal with current and future epidemics in the most efficient and culturally sensitive way.
The author is a medical ethicist at Imperial College, LondonReuse content