Article

Transmission Dynamics and Prospects for the Elimination of Canine Rabies

Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.
PLoS Biology (Impact Factor: 11.77). 03/2009; 7(3):e53. DOI: 10.1371/journal.pbio.1000053
Source: PubMed

ABSTRACT Author Summary

Canine rabies has been successfully eliminated from Western Europe and North America, but in the developing world, someone dies every ten minutes from this horrific disease, which is primarily spread by domestic dogs. A quantitative understanding of rabies transmission dynamics in domestic dog populations is crucial to determining whether global elimination can be achieved. The unique pathology of rabies allowed us to trace case-to-case transmission directly, during a rabies outbreak in northern Tanzania. From these unusual data, we generated a detailed analysis of rabies transmission biology and found evidence for surprisingly low levels of transmission. We also analysed outbreak data from around the world and found that the transmission of canine rabies has been inherently low throughout its global historic range, explaining the success of control efforts in developed countries. However, we show that when birth and death rates in domestic dog populations are high, such as in our study populations in Tanzania, it is more difficult to maintain population-level immunity in between vaccination campaigns. Nonetheless, we conclude that, although the level of vaccination coverage required is higher than would be predicted from naïve transmission models, global elimination of canine rabies can be achieved through appropriately designed, sustained domestic dog vaccination campaigns.

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    • "Canine rabies is responsible for more than 99% of the human cases in Asia and Africa (Cleaveland et al., 2006). In the United States, dog rabies has been largely brought under control through pet vaccination programs and the number of human cases has declined dramatically during the past 60 years (Hampson et al., 2009). Most of the human cases in the USA have been associated with RABV found in bats, particularly the silver-haired bats with no obvious recognized exposure history (Messenger et al., 2003; Morimoto et al., 1996). "
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    • "Finer scale spatial resolution data, such as habitat variability, population densities, abundance, behavioural characteristics and topographical features, need to be incorporated into models to more accurately predict the spread of rabies and therefore facilitate effective control strategies (Smith et al., 2002; Hampson et al., 2009). A number of complex models have been developed including agent-based simulation models (Hampson et al., 2009), interactive network models (Smith et al., 2002; Russell et al., 2006; Craft and Caillaud, 2011), partial or fully stochastic models (Mjolsness et al., 2009; Jensen and Bachtrog, 2011) and coupled stochastic susceptible–exposed–infectious–removed models (Duke- Sylvester et al., 2011; Panjeti and Real, 2011). More recently, the need to include natural barriers in rabies modelling (for example, mountain ranges, rivers and lakes) has been identified as these have been shown to alter "
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