The origin and phylogeography of dog rabies virus

Abstract

Rabies is a progressively fatal and incurable viral encephalitis caused by a lyssavirus infection. Almost all of the 55 000 annual rabies deaths in humans result from infection with dog rabies viruses (RABV). Despite the importance of rabies for human health, little is known about the spread of RABV in dog populations, and patterns of biodiversity have only been studied in limited geographical space. To address these questions on a global scale, we sequenced 62 new isolates and performed an extensive comparative analysis of RABV gene sequence data, representing 192 isolates sampled from 55 countries. From this, we identified six clades of RABV in non-flying mammals, each of which has a distinct geographical distribution, most likely reflecting major physical barriers to gene flow. Indeed, a detailed analysis of phylogeographic structure revealed only limited viral movement among geographical localities. Using Bayesian coalescent methods we also reveal that the sampled lineages of canid RABV derive from a common ancestor that originated within the past 1500 years. Additionally, we found no evidence for either positive selection or widespread population bottlenecks during the global expansion of canid RABV. Overall, our study reveals that the stochastic processes of genetic drift and population subdivision are the most important factors shaping the global phylogeography of canid RABV.

Rabies virus strains circulating in Bhutan: implications for control

“…Many of these genes have been targeted for molecular studies. The N genes are highly conserved and have been extensively employed for rabies diagnosis using RT-PCR and other genetic analyses (Smith et al, 1992;Kuzmin et al, 2004;Denduangboripant et al, 2005;Bourhy et al, 2008). These studies have provided clearer understanding about the epidemiology of rabies virus distribution in the world.…”

Evolutionary history of dog rabies in Brazil

“…24 -1.28610 23 substitutions per site per year) (Badrane & Tordo, 2001;Bourhy et al, 2008;Hanada et al, 2004;Hughes et al, 2004;Talbi et al, 2009), and the 95 % highest probability density (HPD) values of the divergence times largely overlapped among the estimates for each node (Table 1).…”

“…This hypothesis, of rabies having a European origin, is supported by phylogenetic analyses of RABV. Dog RABV isolates collected from Africa and the Americas, both of which were colonized by Europeans, cluster together with isolates from Europe to form what has been referred to as the 'cosmopolitan cluster' (Badrane & Tordo, 2001;Bourhy et al, 2008;Nadin-Davis & Bingham, 2004;Smith et al, 1992). The cosmopolitan cluster also contains carnivore-related RABV isolates from the Middle East, Asia and Russia.…”

Disease Introduction by Aboriginal Humans in North America and the Pleistocene Extinction

“…The first settlers of the Americas brought domestic dogs from Asia with them (Leonard et al 2002), which could have also carried new disease to the Americas. However, most potentially lethal diseases that affect dogs and other Carnivora appear of recent evolutionary origin or were introduced at the time of European contact, including canine rabies (introduced 600 BP, Bourhy et al 2008), parvovirus (Carmichael 2005), and canine distemper (Norrby et al 1985).…”