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Mathematical models of mosquito-borne pathogen transmission originated in the early twentieth century to provide insights into how to most effectively combat malaria. The foundations of the Ross–Macdonald theory were established by 1970. Since then, there has been a growing interest in reducing the public health burden of mosquito-borne pathogens and an expanding use of models to guide their control. To assess how theory has changed to confront evolving public health challenges, we compiled a bibliography of 325 publications from 1970 through 2010 that included at least one mathematical model of mosquito-borne pathogen transmission and then used a 79-part questionnaire to classify each of 388 associated models according to its biological assumptions. As a composite measure to interpret the multidimensional results of our survey, we assigned a numerical value to each model that measured its similarity to 15 core assumptions of the Ross–Macdonald model. Although the analysis illustrated a growing acknowledgement of geographical, ecological and epidemiological complexities in modelling transmission, most models during the past 40 years closely resemble the Ross–Macdonald model. Modern theory would benefit from an expansion around the concepts of heterogeneous mosquito biting, poorly mixed mosquito-host encounters, spatial heterogeneity and temporal variation in the transmission process.

Henipaviruses cause fatal infection in humans and domestic animals. Transmission from fruit bats, the wildlife reservoirs of henipaviruses, is putatively driven (at least in part) by anthropogenic changes that alter host ecology. Human and domestic animal fatalities occur regularly in Asia and Australia, but recent findings suggest henipaviruses are present in bats across the Old World tropics. We review the application of the One Health approach to henipavirus research in three locations: Australia, Malaysia and Bangladesh. We propose that by recognising and addressing the complex interaction among human, domestic animal and wildlife systems, research within the One Health paradigm will be more successful in mitigating future human and domestic animal deaths from henipavirus infection than alternative single-discipline approaches. © Springer-Verlag Berlin Heidelberg 2013.

Emerging zoonoses threaten global health, yet the processes by which they emerge are complex and poorly understood. Nipah virus (NiV) is an important threat owing to its broad host and geographical range, high case fatality, potential for human-to-human transmission and lack of effective prevention or therapies. Here, we investigate the origin of the first identified outbreak of NiV encephalitis in Malaysia and Singapore. We analyse data on livestock production from the index site (a commercial pig farm in Malaysia) prior to and during the outbreak, on Malaysian agricultural production, and from surveys of NiV's wildlife reservoir (flying foxes). Our analyses suggest that repeated introduction of NiV from wildlife changed infection dynamics in pigs. Initial viral introduction produced an explosive epizootic that drove itself to extinction but primed the population for enzootic persistence upon reintroduction of the virus. The resultant within-farm persistence permitted regional spread and increased the number of human infections. This study refutes an earlier hypothesis that anomalous El Nino Southern Oscillation-related climatic conditions drove emergence and suggests that priming for persistence drove the emergence of a novel zoonotic pathogen. Thus, we provide empirical evidence for a causative mechanism previously proposed as a precursor to widespread infection with H5N1 avian influenza and other emerging pathogens.

This chapter reviews recent research on the emergence of the Nipah and Hendra viruses, two lethal zoonotic paramyxoviruses that first emerged from fruit bat reservoirs in Malaysia in 1999 and Australia in 1994, respectively. Large-scale environmental changes such as deforestation, intensification of agriculture, and encroachment of human populations into wildlife habitats may have driven changes in fruit bat migration patterns, feeding behavior, and the dynamics of viral transmission to promote the emergence of these pathogens. For example, fruiting trees planted next to hog containment facilities in Malaysia provide feeding and roosting sites for fruit bats that harbor the Nipah virus. These sites provide opportunities for pathogen spillover from bats to pigs, and ultimately to humans. The link between fruiting trees at hog farms and Nipah emergence has led to livestock management plans that specify buffer zones at pig farms where fruit trees are excluded.

This presentation talks about endangered species legislation. Because of habitat changes such as dams, agriculture, logging, and pollution in the rivers of the United States, many species of freshwater mussels have become extinct or are threatened with extinction. These factors bring the Endangered Species Act and freshwater mussels together. Presently there are 25 species of mussels listed as endangered under the Act. There are an additional 48 mussel species in the Southeast alone that are being considered as candidates for listing. Eleven of these are thought to be already extinct., This article is from 'Report of Freshwater Mussels Workshop Held at St. Louis, Missouri on 26-27 October 1982,' AD-A139 620, p35-41.