Large-scale lagovirus disease outbreaks in European brown hares (Lepus europaeus) in France caused by RHDV2 strains spatially shared with rabbits (Oryctolagus cuniculus)

Abstract

Rabbit haemorrhagic disease virus (RHDV) is a lagovirus that causes rabbit haemorrhagic disease (RHD) in European rabbits (Oryctolagus cuniculus). In 2010, a new genotype called RHDV2 emerged in France. It exhibits a larger host range than classical RHDV strains by sporadically infecting different hare species, including the European hare (Lepus europaeus). Phylogenetic analyses revealed that closely related RHDV2 strains circulate locally in both hares and rabbits, and therefore that RHDV2 strains infecting hares do not belong to a lineage that has evolved only in this species. We showed that RHDV2 is widely distributed in France and that it was responsible for more than a third of cases of lagovirus disease in European hare populations in 2015. The oldest RHDV2 positive hare was sampled in November 2013 and we reported two hares co-infected by EBHSV and RHDV2. All together, our results raise important epidemiological and evolutionary issues. In particular, along with the potential emergence of recombinant EBHSV/RHDV2 strains in hares, the enlargement of the host range changes the host population structure of RHDV2 and may alter the impact of the virus on rabbit and hare populations.Electronic supplementary materialThe online version of this article (doi:10.1186/s13567-017-0473-y) contains supplementary material, which is available to authorized users.

Elucidation of the pathology and tissue distribution of Lagovirus europaeus GI.2/RHDV2 (rabbit haemorrhagic disease virus 2) in young and adult rabbits (Oryctolagus cuniculus)

“…In addition, while animals younger than 5–8 weeks of age are highly resistant to the development of clinical disease following infection with L. europaeus GI.1 viruses, kittens as young as 11 days of age can succumb to disease and death from infection with L. europaeus GI.2 [ 13 ]. Finally, species barriers are less rigid within the Leporidae family, as L. europaeus GI.2 viruses can cause clinical disease and death in various hare species [ 16 – 20 ].…”

The discovery of three new hare lagoviruses reveals unexplored viral diversity in this genus

“…This resulted in the discovery of three new hare viruses: Hare calicivirus Australia-1 (HaCV-A1), Hare calicivirus Australia-2 (HaCV-A2) and Hare calicivirus Australia-3 (HaCV-A3). Prior to this, the only lagovirus detected in hares in Australia was RHDV2 (41), which is primarily a rabbit virus, and phylogenetic evidence suggests that RHDV2 infection in hares in Australia occurred as a result of transient spill-over events (42, 49). While HaCV-A3 was only found in one animal, the other two new viruses were both detected in almost one third of hares tested at the Hamilton, VIC site, during both sampling periods (one year apart).…”

“…Apart from RHDV 2 , no other lagoviruses have been detected in hares in Australia. In Europe, Lepus europaeus is affected by the pathogenic lagovirus EBHSV (43-48), which has never been detected in Australia, as well as RHDV2, which has been detected in multiple hare species (41, 49-52). Two additional, presumably benign, hare caliciviruses from Europe (denoted GII.2), have recently been reported (13, 15, 16) and it is unknown whether similar viruses are present in Australia.…”

Rabbit haemorrhagic disease virus type 2 in hares in England

“…Disease has also been confirmed in Sardinian Cape hares ( Lepus capensis mediterraneus ) in 2011,3 farmed Italian hares ( Lepus corsicanus ) in 2012,4 and European brown hares ( Lepus europaeus ) in Italy in 2012, Spain in 2014,5 France in 20136 and Australia in 2016 7…”