Environmental Change and Human Health in the Brazilian Amazon

The Amazon is a vast region of about 7 million km², encompassing nine countries in the northern part of South America. Around 70% of the Amazon, or approximately 5 million km², are within the Brazilian National boundary (Figure 1). It is, in many aspects, a unique region characterised by the largest stock of biological diversity in the world, an extensive network of rivers, the persistence of traditional Indian population — some still isolated from contacts with modern society — and significant mineral reserves.Around 65% of the Brazilian Amazon region is covered by the different sub-types of the tropical rainforest, with some 100.00 km² of it periodically flooded every year. Another 1.3 million km² are covered with other types of vegetation, especially tropical savannahs. The Brazilian Amazon is home to about 20 million inhabitants of which only 0.8% are Indian; the urbanisation rate in the region is about 60%.Although industrial exploitation of the natural resources of the region has been under way since the last quarter of the 19^th century, it was only in the last 30 years that human intervention in the Amazonian ecosystems has been followed by major negative impacts. This has happened for economic, social and geopolitical reasons and included the opening of new roads, the fiscal incentives for industrialisation in urban areas, building of dams for the generation of hydroelectricity, intensive mining schemes, settlements for agricultural development and cattle raching. This has brought profound social, cultural as well as environmental changes, often resulting in benefits for only a small part of the population. Among the adverse environmental impacts, deforestation stands as the most important one due to its large extension, rapid progress and global and multi-factorial consequences. All these processes — social as well as environmental — have been changing the disease profile in the region (Figure 2). With the intense and widespread exploitation of the Amazon, new diseases are emerging, others are being introduced and the old ones are becoming out of control.