The Role of Phylogeography in the Control of Wildlife Rabies in Turkey
Rabies has been endemic in Turkey throughout the modern era and it is probable that the disease has been present since antiquity. Until the late 1990’s, the epidemiology of rabies in Turkey was dog mediated, principally in urban areas throughout the country. This changed in 1999 with the appearance of a focus of rabies cases in red foxes (Vulpes vulpes) around the western Turkish city of Izmir. Phylogenetic analysis of rabies virus isolates from fox submissions from this area and from a range of animals from the whole of the country suggested that this event resulted from a cross-species transmission event from the local dog population to the peri-urban fox population. Subsequent monitoring documented the movement of this epizootic away from the initial focus south and eastwards. All the evidence from a number of studies pointed towards the establishment of a rabies reservoir within the red fox. Increases in rabies cases in cattle and a single case of human rabies were directly linked to this outbreak of wildlife rabies by phylogenetic analysis of the infecting virus. In an attempt to control the epizootic in the fox population, oral vaccination was planned in 2002. However, a three year program of oral vaccination was not implemented until 2008. Despite the success of this approach in the targeted area, the epizootic had spread beyond the vaccination zone and has continued to move north, east and south in Turkey. This chapter will begin by reviewing in detail the emergence of wildlife rabies in Turkey and the contribution phylogenetic analysis has made to the understanding of this rabies epizootic. It will then show how knowledge of the molecular epidemiology of rabies, linked to effective disease surveillance in Turkey, can assist in the design of future oral vaccination programs.