Traditional and Molecular Techniques for the Study of Emerging Bacterial Diseases: One Laboratory’s Perspective

Identification of emerging bacterial pathogens generally results from a chain of events involving microscopy, serology, molecular tools, and culture. Because of the spectacular molecular techniques developed in the last decades, some authors think that these techniques will shortly supplant culture. The key steps that led to the discovery of emerging bacteria have been reviewed to determine the real contribution of each technique. Historically, microscopy has played a major role. Serology provided indirect evidence for causality. Isolation and culture were crucial, as all emerging bacteria have been grown on artificial media or cell lines or at least propagated in animals. With the use of broad-range polymerase chain reaction, some bacteria have been identified or detected in new clinical syndromes. Culture has irreplaceable advantages for studying emerging bacterial diseases, as it allows antigenic studies, antibiotic susceptibility testing, experimental models, and genetic studies to be carried out, and remains the ultimate goal of pathogen identification

A emergência das doenças emergentes e as doenças infecciosas emergentes e reemergentes no Brasil The emergence of emerging diseases and emerging and reemerging infectious diseases in Brazil

O artigo discute a emergência do conceito de doenças infecciosas emergentes e reemergentes. Postula-se que o conceito surge frente às limitações da teoria da transição epidemiológica em explicar as tendências recentes da morbidade e mortalidade. São discutidas as bases da teoria da transição epidemiológica e as razões de sua superação. Em seguida, são apresentados o conceito de doenças emergentes e reemergentes, os fatores relacionados à emergência das doenças infecciosas e as principais ocorrências no Brasil. Por fim, são abordados os desafios colocados pela emergência e reemergência das doenças infecciosas, e propostas para o seu enfrentamento.<br>This article discusses the emergence of the concept of emerging and reemerging infectious diseases. It argues that the concept surfaces due to the limits of the epidemiologic transition theory in explaining the current trends in morbidity and mortality. The bases of the epidemiologic transition theory are discussed, as well as the reasons for its limits. Then, the concept of emerging and reemerging infectious diseases, the factors related to them, and the major episodes of emergence and reemergence of diseases in Brazil are presented. Finally, the article discusses the challenges brought by the emergence and reemergence of infectious diseases, and the proposals to face them