The mechanisms that govern the relation between personal mobility and transmission of the AIDS virus (HIV) are still poorly known. Surveys conducted in the River Senegal Valley by two demographers from the IRD and the University of Montreal suggest that the way individuals returning to their community of origin deal with sexual risks depends on the migratory paths (internal or international migrations) and the social pressures prevailing in that community. Such influences cause most migrants to give up any risky sexual behaviour they might have adopted when they were away. Migration could therefore play only a small role in spreading HIV within the home community. This could partly explain why AIDS prevalence in Senegal remains lower than in other West African countries.
Ever since AIDS appeared, migration has been thought to be a driving force behind the epidemic. The disease is often represented either as an "imported pathology", migrants being the disease (or at least risk), carriers or as a "pathology of adaptation". Migrants, mainly young men who move around to find work, are subjected to the constraints of a new environment they find in the host region or country. They therefore become economically, socially and emotionally more vulnerable. This situation encourages changes in their sexual behaviour, like multiplication of casual partners and resorting to prostitutes.
Demographers Richard Lalou (IRD) (1) and Victor Piché (University of Montreal) focused on this relation between mobility and sexual behaviour. Findings of surveys performed in 2000 in the River Senegal Valley, among 1320 persons aged between 15 and 49 years old, provided data on the routes taken by the migrants and their personal situations. The ability of these migrants to handle sexual risks of transmitting HIV differed according to the social contexts of the communities they were going back into. Two locations with highly contrasting social situations were studied: the urban centre of Richard-Toll (in the lower valley) and the rural area of Matam (in the middle of the valley). At Richard-Toll international emigration was turned towards countries having low HIV prevalence (Mauritania), whereas the Matam area is the source of substantial international emigration towards countries with higher prevalence (Ivory Coast, Central Africa). In spite of these movements towards countries with high prevalence of HIV seropositive cases, the infection rate in the Matam area remained constant in the years between 1990 and 2002 (about 2%). In these surveys, international mobility, which aims for an African country or another continent, has been distinguished from internal mobility which concerns movements within the country, mainly towards the large towns and cities (Dakar, Saint-Louis and Thiès), and short temporary trips away.
Hélène Deval | EurekAlert!
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