Angelo Jussara Rafael, Katsuragawa Tony Hiroshi, Sabroza Paulo Chagastelles, de Carvalho Lino Augusto Sander, Silva Luiz Hildebrando Pereira da, Nobre Carlos Afonso
Departamento de Endemias Samuel Pessoa, Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz (ENSP/FIOCRUZ), Rio de Janeiro, Rio de Janeiro, Brasil.
Fundação Oswaldo Cruz - Rondônia (Fiocruz-RO), Porto Velho, Rondônia, Brasil.
PLoS One. 2017 Feb 21;12(2):e0172330. doi: 10.1371/journal.pone.0172330. eCollection 2017.
This study aims to describe the role of mobility in malaria transmission by discussing recent changes in population movements in the Brazilian Amazon and developing a flow map of disease transmission in this region.
METHODOLOGY/PRINCIPAL FINDINGS: This study presents a descriptive analysis using an ecological approach on regional and local scales. The study location was the municipality of Porto Velho, which is the capital of Rondônia state, Brazil. Our dataset was obtained from the official health database, the population census and an environmental database. During 2000-2007 and 2007-2010, the Porto Velho municipality had an annual population growth of 1.42% and 5.07%, respectively. This population growth can be attributed to migration, which was driven by the construction of the Madeira River hydroelectric complex. From 2010 to 2012, 63,899 malaria-positive slides were reported for residents of Porto Velho municipality; 92% of the identified samples were autochthonous, and 8% were allochthonous. The flow map of patients' movements between residential areas and areas of suspected infection showed two patterns of malaria transmission: 1) commuting between residential areas and the Jirau hydropower dam reservoir, and 2) movements between urban areas and farms and resorts in rural areas. It was also observed that areas with greater occurrences of malaria were characterized by a low rate of deforestation.
The Porto Velho municipality exhibits high malaria endemicity and plays an important role in disseminating the parasite to other municipalities in the Amazon and even to non-endemic areas of the country. Migration remains an important factor for the occurrence of malaria. However, due to recent changes in human occupation of the Brazilian Amazon, characterized by intense expansion of transportation networks, commuting has also become an important factor in malaria transmission. The magnitude of this change necessitates a new model to explain malaria transmission in the Brazilian Amazon.
本研究旨在通过讨论巴西亚马逊地区人口流动的近期变化，并绘制该地区疾病传播流程图，来描述流动性在疟疾传播中的作用。
方法/主要发现：本研究采用生态方法在区域和地方尺度上进行描述性分析。研究地点为巴西朗多尼亚州首府波多韦柳市。我们的数据集来自官方健康数据库、人口普查和环境数据库。2000 - 2007年以及2007 - 2010年期间，波多韦柳市的年人口增长率分别为1.42%和5.07%。这种人口增长可归因于迁移，其驱动力是马德拉河水力发电综合体的建设。2010年至2012年，波多韦柳市居民报告了63899份疟疾阳性玻片；已鉴定样本中92%为本地病例，8%为外地病例。患者在居住区和疑似感染区域之间的流动流程图显示了两种疟疾传播模式：1）居住区与吉劳水电大坝水库之间的通勤，以及2）城市地区与农村地区的农场和度假村之间的流动。还观察到疟疾发病率较高的地区森林砍伐率较低。
波多韦柳市疟疾流行程度高，在将寄生虫传播到亚马逊地区的其他城市甚至该国非流行地区方面发挥着重要作用。迁移仍然是疟疾发生的一个重要因素。然而，由于巴西亚马逊地区近期人类居住情况的变化，其特点是交通网络的密集扩张，通勤也已成为疟疾传播的一个重要因素。这种变化的程度需要一个新的模型来解释巴西亚马逊地区的疟疾传播。
