Jet set pets: examining the zoonosis risk in animal import and travel across the European Union

Fooks, Anthony R; Johnson, Nicholas

Rabies is a progressive encephalitis that is invariably fatal. It is caused by viruses of the genus lyssavirus, of which the type species is the rabies virus. 18 All mammals are susceptible to the disease, but only a small number are capable of acting as a reservoir species; key among these is the domestic dog. Infected animals shed virus into saliva, and transmission occurs following a bite from a rabid animal, usually a reservoir host. This allows the virus to bypass physical barriers, such as clothing and skin, leading to infection of peripheral nerves. Once the virus infects the central nervous system, the infected host begins to show signs of the disease and therapeutic options are limited to experimental approaches that have not proven successful. 19 However, the period between contact with a rabid animal and invasion of the central nervous system is sufficiently long to allow effective post-exposure vaccination that can, if administered shortly after contact, prevent development of disease. 20 Access to the rabies vaccine, even in rabies-free countries where human cases occur regularly due to exposure overseas, 21 is essential to protect against developing disease. Post-exposure vaccination is also recommended for bites from bats that transmit rabies virus in the Americas and non-rabies lyssaviruses in the rest of the world. 22 This includes the bat lyssaviruses found in the European insectivorous bat populations. However, the efficacy of current vaccines against the full range of viruses within the genus is not complete due to antigenic variation between the rabies virus 23 used to formulate veterinary and human vaccines and the more divergent lyssaviruses. 24 Where dog populations are not strictly controlled and anti-rabies measures are limited, the disease is a major public health problem. This is particularly so in Africa and Asia where the main burden of human disease falls. 25 Through persistent application of rabies control in dogs, the number of human cases of the disease has declined dramatically in Latin America. 9 For reasons that are not understood, rabies virus is found in many species of New World bats. 22 This includes many insectivorous and frugivorous bat species, and the common vampire bat (Desmodus rotundus). Due to the difficulty in controlling rabies in the bat population, elimination of rabies virus from the Americas is unlikely. Old World bat species harbor viruses from the same genus that can cause disease on rare occasions. 26 Dog rabies has declined in Europe since the Second World War, but in its place the dominant reservoir for disease has been the red fox (Vulpes vulpes). 27 However, this has been successfully controlled and the disease eliminated from many countries by oral vaccination via distribution of baited vaccine. 28 Despite these successes, fox rabies can reemerge by crossing borders between endemic and rabies-free areas. This recently occurred in Italy in 2008 and required repeated oral vaccination campaigns over 3 years to regain freedom from the disease. 29 Occasional cases of dog rabies are reported in Eastern Europe. 30, 31 These may represent spill-over infection from red fox populations, although there is also the possibility that pockets of dog rabies persist in some urban areas. There is also the risk of introducing rabies through accidental importation where a dog may be incubating virus without showing signs of disease and through illegal movement of dogs. In 2008, an animal charit