The Urban Gradient in Malaria-Endemic Municipalities in Acre: Revisiting the Role of Locality

Abstract

Urbanization has altered the distribution of diseases of public health importance along gradients of human occupation. Adopting dichotomous urban/rural categories to explain differences in the risk of exposure, as well as the prevention of diseases is insufficient. In this paper, we present the potential of representations based on the gradient perspective to characterize the living spaces of municipalities where malaria is endemic in northwest Acre. Inventoried data in 40 localities in the Mâncio Lima and Rodrigues Alves municipalities and information on land use and land cover obtained from the TerraClass Database were used to characterize the urban spatial forms and their social content. Results showed a gradient of intensities: from municipal seats to the most connected localities through the road network to riverine communities. Based on the results, we hope to advance the discussion about the use of normative definitions of “urban” and “rural” for public policies and actions to control and eliminate malaria, considering the position of each locality in its own locally referenced urban gradient.

Molecular evidence of sustained urban malaria transmission in Amazonian Brazil, 2014–2015

“…Although 30% of urban residents in Mâncio Lima report having spent at least one night in one or more rural sites within the past 6 months, no single locality with intense malaria transmission stands out as the main travel destination. In contrast, the most commonly travel destinations, mentioned by 3.5% of urban residents (I. C. Johansen, unpublished data), were riverine settlements surrounded by rainforest along the Moa and Azul rivers, where malaria incidence remains low [36, 37].…”

Human mobility and urban malaria risk in the main transmission hotspot of Amazonian Brazil

“…We note that urban areas in Brazil are defined according to relatively arbitrary administrative rules that do not necessarily consider population density and other internationally adopted criteria [32]. Here we delimitate the town of Mâncio Lima essentially as done by the Brazilian Institute of Geography and Statistics (IBGE) but extend the urban area to two urbanized neighborhoods (Iracema to the Northwest and Pé da Terra to the Southeast), which are situated along the main road that crosses the town, following the "urbanicity" criteria developed by Dal'Asta and colleagues [33] for use in this setting. These two neighborhoods had been originally classified as rural by IBGE.…”

“…The presence of multi-sited households in the Amazon [28] is part of a broader process called extended urbanization [23][24][25]. The traditional rural-urban divide in the region has been gradually replaced by a continuous gradient of "urbanicity"-typically urban features are extended to rural communities while towns and cities retain some "rurality" [33]. Our findings suggest that human mobility across the rural-urban gradient, mostly motivated by subsistence or commercial farming in peri-urban settlements, poses a continuous risk of malaria introduction into more urbanized and densely populated spaces.…”

Emerging arboviruses in the urbanized Amazon rainforest

“…Importantly, Ae aegypti dwell in water holding containers, which are abundant in urban landscapes. 11 12 Dengue vectors have been expanding from urban centers to neighboring rural areas and into the urbanized forest (areas with increased presence of non-indigenous settlements but with gradients more complex than simple city versus rural classifications 13 14 ). In the Peruvian Amazon, for example, proximity to Iquitos has been shown to increase the odds of Aedes ’s establishment.…”