Background: Human mobility is an important determinant of malaria distribution and can explain different patterns of (re)introduction, circulation and persistence of malaria. In order to understand the association between human mobility patterns and the probability of getting malaria, this study revisited a household survey conducted in 2015 in Alto Juruá region, Acre state, Brazil. This region registers one the greatest malaria burden in Brazil. The goal of this work is to estimate the contribution of human commutation to the persistence of malaria.
Methods: Data from the origin-destination survey was used to describe the intensity and motivation for commutation between rural settlements and urban areas in two municipalities, Mâncio Lima and Rodrigues Alves. The relative time-person spent in each locality per household was estimated. A logistic regression model was fitted to estimate the effect of commuting on the probability of getting malaria for a householder from a zone of residence commuting to another zone.
Results: Our main results suggests that this population is not very mobile. $96\%$ of households reported spending more than $90\%$ of their yearly person-hour at localities within the same zone. Study and work are the most prevalent motivation to displace, $40.5\%$ and $29.5\%$ respectively. Spending person-hours in urban Rodrigues Alves conferred relative protection to the residents of urban Mâncio Lima. On the other hand, spending time in rural Rodrigues Alves increased the probability of malaria, but not significant in rural Mâncio Lima. For urban Rodrigues Alves residents, spending time in urban and rural Mâncio Lima and rural Rodrigues Alves increased the probability of malaria, more so if going to the latter.
Conclusion: The results suggests that the place one lives is a stronger determinant of the probability of getting malaria in Alto Juruá region and this can be a natural consequence of the low mobility and the local environment. The heterogeneity of malaria transmission in Brazil highlights the importance of microregion-targeted intervention since their risk signature within each municipality is quite different, despite being direct geographical neighbors. In addition, it is essential that intersectoral public policies be the basis for health mitigation actions.