Hépatites d'origine virale des léporidés : introduction et hypothèses étiologiques

Abstract

In less than ten years, two very serious viral hepatic diseases have spread through Leporidae populations (rabbits and hares) in numerous countries. In May 1989, the Office International des Epizooties designated this new disease of rabbits "viral haemorrhagic disease" and entered it as a List B disease in the International Animal Health Code. Clinically, the disease is very similar to the European brown hare syndrome. However, numerous uncertainties prevail today on the true nature of the viruses of the two species. Although they are related, the viruses appear to be different and cross infection between species has given contradictory results. Hepatitis of Leporidae have probably existed in Europe for several years, although their viral aetiology has been demonstrated only recently. The acute form has occurred in hares in Northern Europe since approximately 1980, while the inapparent (or ignored) form has been present in rabbits in Czechoslovakia since 1975. These diseases of Leporidae are true viral hepatitis which, in their fulminating forms, bear a remarkable resemblance to human viral hepatitis (B and non-A non-B) with regard to clinical symptoms, pathological lesions and mode of transmission. The dominant faecal-oral transmission observed for types A and E hepatitis would explain the particular susceptibility of family-kept rabbits, as they are fed potentially contaminated fodder. As the clinically similar fulminating hepatitis in human beings is caused by a diversity of viruses (both RNA and DNA), the disease in Leporidae might also be caused by different viruses. Although there has been no report of human infection from an animal source, sufficient similarities exist between Leporidae and human viral hepatitis to encourage joint research in the specialised medical fields.

Rabbit haemorrhagic disease and the biological control of wild rabbits, Oryctolagus cuniculus, in Australia and New Zealand

“…European scientists (Morisse et al 1991;Rodak et al 1991) reported that even in the absence of maternal antibodies, domestic rabbits younger than 4 weeks did not develop clinical signs or pathological lesions. Nevertheless, there was replication of the virus following infection and the young rabbits developed lifelong immunity.…”

“…Nevertheless, a new disease -'Malattia-X' -was recognised among domestic rabbits in Italy in 1986 (Cancellotti and Renzi 1991) and soon appeared in other countries in Europe (Morisse et al 1991). This new disease was at first regarded as being due to a toxin, or to fallout from the Chernobyl disaster.…”

“…By 1988, rabbit haemorrhagic disease, or RHD as it eventually became known, occurred not only in Europe but had also spread to domestic rabbits in the Russian Federation, the Middle East and parts of Africa, Cuba, Mexico, the USA, India and Reunion Island (Morisse et al 1991). It was probably spread by trade in rabbit meat, or by shipment of rabbits infected before dispatch.…”

Recombinant Lactobacillus casei Expressing Capsid Protein VP60 can Serve as Vaccine Against Rabbit Hemorrhagic Disease Virus in Rabbits

“…This disease was first reported in China in 1984, and has, since, spread rapidly around the world in less than 10 years, causing considerable economic losses in the rabbit industry and impacting the ecology of wild rabbit populations [1,2,5,6]. In 1989, OIE designated this illness as a viral hemorrhagic disease and added it to List B of the International Animal Health Code [7]. Subsequently, a novel lagovirus, GI.2, emerged in France in 2010 [4].…”

“…Vaccination is the main approach for controlling RHDV because no effective treatment is available for this disease. Inactivated vaccines against RHDV were introduced in the early 1990s, improving the survival of rabbits on rabbit farms [7,14]. However, RHDV inactivated vaccines are manufactured using the livers of rabbits infected with RHDV.…”