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: 9.34). 03/2009; 7(3):e53. DOI: 10.1371/journal.pbio.1000053
Source: PubMed

ABSTRACT

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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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    • "R 0 among the domestic dog population in Asian or African countries has been reported to be 1.0–1.8 (Hampson et al., 2009; Zinsstag et al., 2009). Therefore, the number of reported cases and the months required to report the first case were estimated using this range of R 0 (R 0 = 1.0–2.0), "
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    • "These distributions were derived from both natural and experimental rabies. The incubation period estimated in our study appears to be longer than that estimated by Hampson et al. (2009). They, based on observations of rabid animals in Tanzania, estimated the incubation period of rabies to be 22.3 (95% CI: 20.0–25.0) "
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    • "In more than 99% of all cases of human rabies, the virus is transmitted directly by dogs (Knobel et al., 2005). Canine rabies can be eliminated, as demonstrated in North America, Western Europe, Japan, areas of South America and parts of Asia (Hampson et al., 2009). Advancements in post exposure prophylaxis (PEP) mean that if a person can access the appropriate post exposure vaccination and immunoglobulin therapy in a timely manner they are likely to survive (Hampson et al., 2011). "
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