Article

Ecological Origins of Novel Human Pathogen

Centre for Infectious Diseases, University of Edinburgh, Edinburgh, United Kingdom.
Critical Reviews in Microbiology (Impact Factor: 6.09). 02/2007; 33(4):231-42. DOI: 10.1080/10408410701647560
Source: PubMed

ABSTRACT A systematic literature survey suggests that there are 1399 species of human pathogen. Of these, 87 were first reported in humans in the years since 1980. The new species are disproportionately viruses, have a global distribution, and are mostly associated with animal reservoirs. Their emergence is often driven by ecological changes, especially with how human populations interact with animal reservoirs. Here, we review the process of pathogen emergence over both ecological and evolutionary time scales by reference to the "pathogen pyramid." We also consider the public health implications of the continuing emergence of new pathogens, focusing on the importance of international surveillance.

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    ABSTRACT: Background Time series models can play an important role in disease prediction. Incidence data can be used to predict the future occurrence of disease events. Developments in modeling approaches provide an opportunity to compare different time series models for predictive power. Results We applied ARIMA and Random Forest time series models to incidence data of outbreaks of highly pathogenic avian influenza (H5N1) in Egypt, available through the online EMPRES-I system. We found that the Random Forest model outperformed the ARIMA model in predictive ability. Furthermore, we found that the Random Forest model is effective for predicting outbreaks of H5N1 in Egypt. Conclusions Random Forest time series modeling provides enhanced predictive ability over existing time series models for the prediction of infectious disease outbreaks. This result, along with those showing the concordance between bird and human outbreaks (Rabinowitz et al. 2012), provides a new approach to predicting these dangerous outbreaks in bird populations based on existing, freely available data. Our analysis uncovers the time-series structure of outbreak severity for highly pathogenic avain influenza (H5N1) in Egypt.
    BMC Bioinformatics 08/2014; 15(1):276. DOI:10.1186/1471-2105-15-276 · 2.67 Impact Factor
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    • "Only individuals living in dense forest (presumably with an abundant and diverse primate fauna) showed both polymerase chain reaction (PCR) and serological evidence of SFV infection, suggesting that transmission is greater in more intact forests (Wolfe et al. 2004). Intensive or sustained usage of areas of high biodiversity may also mediate the risk of other emerging and zoonotic diseases from a variety of reservoir hosts (Woolhouse and Gaunt 2007). For instance, the increased disease incidence documented where deforestation is occurring often cannot be ascribed directly to the loss of biodiversity that comes along with deforestation (and thus, to a dilution effect), but rather to the increase in human contact with forested habitat that deforestation entails (Wolfe et al. 2005). "
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    Ecology 04/2014; 95(4):817-32. DOI:10.1890/13-1041.1 · 5.00 Impact Factor
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    • "A number of zoonoses are (re)emerging worldwide, the majority of which present risks to animal and human health [1], [2]. Birds are a key animal reservoir since they maintain and are responsible for the large-scale transmission of many infectious diseases [3]–. In recent years, a number of epidemic outbreaks originating in wild birds have been reported, such as outbreaks of West Nile virus or highly pathogenic H5N1 influenza virus, during which the virus later spread to other species of domestic animals and humans [7]–[11]. "
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