It takes boundaries to create migrants. Beliefs, religion, skin colour, race, ethnic background, language, nationality, all played a role in the constitution of such boundaries throughout human history. On the dark side of the spectrum, these boundaries have always caused a wide range of problems and disasters, ill health and death.

There have been, however, remarkably enlightened and promising spells of viewing aliens crossing borders into other people's backyards. In the 1930s the Chicago School of Sociology, namely Robert E. Park, celebrated migrants as the characters and migration as the force driving the process of civilization (Park 1928). Similarly, G. Simmel in Germany regarded strangers as the truly free and ‘objective’ humans capable of striving for great aims. The ‘marginal man’ of R. E. Park and the ‘truly and objective man’ of G. Simmel are both urban characters, Park and Simmel being the fathers of the sociology of cities.

Yet the most recent history of cities, and of migrants pouring into them, tells a different story. New boundaries appear faster than old ones disappear, marginalising newcomers, inhibiting positive interaction and neglecting opportunities for development. Most people's journey into the breathtakingly fast-growing urban areas terminates in suburbs and slums, and they remain cut off from the glamour of the cities by social and economic boundaries. More than half a century after Park's and Simmel's optimistic views of the role of migrants in social evolution, migrants are more than ever viewed as nothing but a burden, even in countries that would never have come into existence without large-scale migration, and despite the fact that most migrants have contributed to the wealth of the countries which received them.

Undoubtedly migration is a politically and historically highly loaded issue, which explains why studies in this field are not easy to launch. Additionally, there are more immediate obstacles for researchers. In the epidemiologist's world, migration figures most of all as a factor that disturbs the conduct of studies by removing or introducing subjects in the most unpredictable fashion. But if we target migrants as study subjects in their own right, we enter an area where the objects of research can be volatile and for good reasons reluctant to disclose their history and identity.

Throwing light on the interconnectedness of migration and health is an ambitious aim. Both the features we attribute to migrants and our definitions of health are socially constructed and highly variable across time and space. To get a grip on these terms continues to be a struggle and all that has been suggested so far is highly controversial. We have to be aware of this fundamental problem of vague and questionable classification systems when interpreting studies on migration and health. Researchers looking at mixed populations try to tease out differences in outcomes of interest such as morbidity and mortality. Understandably, they dwell on features which appear obviously different at first sight such as skin colour and habits. But then dangerous shortcuts are often taken. Single features are substituted by general terms like ‘race’ and, when this term became obsolete in social sciences, by ‘ethnicity’ (remarkably this change in terminology was mostly not accompanied by semantic change). Race and ethnicity as classification systems have been criticised extensively and the historical record of the concept of race is a series of disasters (Gould 1984; Bhopal 1997). If key variables are vaguely defined, the underlying concepts poorly understood and hard to measure, little is to be expected from studies which dwell on them.

Certainly, there are problems which need to be studied for important practical purposes. The study of the IOM (International Organization for Migration) Tuberculosis Working Group on drug-resistant tuberculosis in Vietnamese refugees in this issue is an example (IOM Tuberculosis Working Group 1998). The data set originated from the Orderly Departure Programme in Vietnam in which IOM is involved. To get Vietnamese refugees smoothly across the Pacific into the US, this is certainly the information needed. But do these studies tell us much about the specific risks of disease in the context of migration? Most likely not. Not migration, but well-known fundamental factors such as starvation, crowding, lack of health services drive tuberculosis transmission and breed multidrug-resistant strains. In postwar SE Asia the Vietnamese people as a whole suffer from high rates of tuberculosis and drug resistance, and those who are migrating form only a small part of the population. The problem applies to both ends of the journey, and misperceptions are equally common on arrival. Generally, migrant-receiving nations see migrants as a major risk factor for the introduction of tuberculosis into their populations. Only very recently has solid evidence been accumulating through molecular epidemiological studies that the contribution to the total burden of tuberculosis in the north through transmission across subpopulation boundaries seems limited (Hermans et al. 1995; Borgdorff et al. 1998). This not only has important repercussions for clearing migrants from this particular stigma, but also for establishing the appropriate public health measures. Suggestions to solve the problem of tuberculosis in migrant-receiving nations have clearly moved beyond targeting tuberculosis in migrants to the insight that global efforts are needed for effective control (Davies 1995; Zuber et al. 1997). Associating tuberculosis with migration without analysing the underlying circumstances and mechanisms is an example of ‘black box epidemiology’ which is so frequently found in research on migration and health.

The literature review on migrants in the European Union (EU) of Carballo and coauthors in this issue impressively shows that the field of migration and health is being dealt with virtually exclusively from the perspective of ill-health of migrants and the risks supposedly originating from them (Carballo et al. 1998). This view, which is reflected in the literature, contributes directly or indirectly to the negative perception, and consequently reception, of migrants. Migrants figure as cost-intensive risk factors, as a political class of excess people or poor creatures who need our mercy and repair; in summary people who take a lot and have nothing to give in return. Muecke has discussed this important issue with refugees as an example (Muecke 1992), and Bhopal argues along the same lines:

‘By emphasising the negative aspects of the health of ethnic minority groups, research may have damaged their social standing and deflected attention from their health priorities’ (Bhopal 1997, page 1751).

Research on migration and health has a long way to go to get its classifications right, to develop a more positive, innovative and comprehensive approach, and to understand more broadly what is implicated in the process of migration – something which has been with us since our very origins.


  1. Top of page
  2. References
  • 1
    Bhopal, R (1997) Is research into ethnicity and health racist, unsound, or important science? British Medical Journal 314, 1751 1756.
  • 2
    Borgdorff, MW, Nagelkerke, N, Soolingen, D, Haas, PE, Veen, J, Embden, JD (1998) Analysis of tuberculosis transmission between nationalities in the Netherlands in the period 1993–95 using DNA fingerprinting. American Journal of Epidemiology 147, 187 195.
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    Carballo, M, Divino, JJ, Zeric, D (1998) Migration and Health in the European Union. Tropical Medicine & International Health 3, 936-944.
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    Davies, PDO (1995) Tuberculosis and migration. The Mitchell Lecture 1994. Journal of the Royal College of Physicians of London 29, 113 118.
  • Gould SJ (1984)
    The Mismeasure of Man. Pelican, London.
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    Hermans, PWM, Messadi, F, Guebrexabher, H, et al (1995) Analysis of the population structure of Mycobacterium tuberculosis in Ethiopia, Tunisia and the Netherlands: usefulness of DNA typing for global tuberculosis epidemiology. Journal of Infectious Diseases 171, 1504 1513.
  • IOM Tuberculosis Working Group, (1998) Outcome of second-line tuberculosis treatment in migrants from Vietnam.
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    Muecke, MA (1992) New paradigms for refugee health problems. Social Science and Medicine 35, 515 523.
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    Park, RE (1928) Human migration and the marginal man. American Journal of Sociology 33, 881 893.
  • 10
    Zuber, PLF, McKenna, MT, Binkin, NJ, Onorato, IM, Castro, KG (1997) Long-term risk of tuberculosis among foreign-born persons in the United States. Journal of the American Medical Association 278, 304 307.