Was malaria present in the Amazon before the European conquest? Available evidence and future research agenda

Most of the evidence available so far suggests that malaria was not present in the New World before the European conquest. However, the timing of the introduction of the disease in the Americas is still a matter of controversy. In this paper we appraise the debate in the context of the Brazilian Amazon, where malaria is, at the present time and has been for several centuries, an important health problem. We review and summarize the available evidence in favor of the introduction of malaria after the conquest based on historical documents, studies in genetics and evolutionary biology, epidemiological issues, and archaeological discoveries. We argue that despite the compelling arguments provided by the extant body of evidence, a more definitive proof is needed. We suggest that archaeology, via analyses of existing skeletal remains from Amazonia using biomolecular techniques, may represent the best (and unique) approach to a definitive resolution of a long-standing debate. We anticipate that in the near future a multidisciplinary effort can be brought together to provide a clear answer to a long standing epidemiological question: Was malaria present in the Amazon before the European conquest?