Introduction: understanding migration and health in
The relationships between migration and health are multiple. There is growing evidence, albeit incomplete, that the process of migration and the health of individuals and communities are inextricably intertwined in complex ways, with implications for those who move, those who are left behind, and those who host migrants. One classic conceptualization of the relationship between migration and health is provided by Hull (1979), who points out that the causal link between migration and health can occur in either direction – the health of individuals and communities may be inﬂuenced by migration, while the health of individuals and communities may stimulate migration. Thus, at the macro-scale, migration may inﬂuence population health, although the effects may be quite difﬁcult to disentangle (Boyle 2004). At the individual level, we know that the relationship between migration and health varies with age (Findley 1988). Younger adults who migrate are generally healthier than non-migrants, while older adults beyond retirement age are more likely to move if they are in poor health and, for the latter group, health is often an important factor which inﬂuences the decision to move. Health can also inﬂuence temporary moves – a growing literature on health tourism, for example, suggests that the use of better or cheaper health care abroad is resulting in new patterns of migration in many parts of the world, including Asia (Borman 2004).