Past, Present and Future of Molecular Technology Applications for the Epidemiology of Bacterial Diseases

Abstract

The evolution of molecular technologies has had a major impact on many fields of research, including epidemiology. At the core of this branch of epidemiology is the need for high specificity typing of disease agents: to confirm trace back of disease to origin, to monitor the spread of disease causing strains, to study population dynamics of the disease strain, to discern endemic/enzootic from epidemic/epizootic infections, to detect the presence of multiple strain (s) in the population and/or individual, to identify modes of transmission of the disease agent from host to host, and to address other epidemiological questions or issues. Molecular subtyping has been generally found to be better than most traditional phenotypic subtyping methods because it is usually more discriminating and less influenced by the organisms’ responses to environmental cues. A large number of molecular techniques have been adapted for application to epidemiological issues, and different techniques are needed for different aspects of investigation. This review examines the most commonly used techniques for typing and/or characterizing bacteria for epidemiological purposes. It includes a historical perspective to help explain why certain techniques may be preferred over others, as well as a prediction of the future directions that epidemiologists may go in applying molecular technologies for their work.