Recombination in rabbit haemorrhagic disease virus: Possible impact on evolution and epidemiology

Abstract

Rabbit haemorrhagic disease (RHD) was first recognised in 1984 following the introduction of apparently healthy rabbits into China from Germany. The aetiological agent Rabbit haemorrhagic disease virus (RHDV) has subsequently killed hundreds of millions of domestic and wild rabbits particularly in Europe, China and Australia. Previously, using phylogenetic analysis we have attempted to understand the underlying factors that determine why this virus emerged, and why it has such an unpredictable epidemiology. Here we report the use of tree congruency supported by bootscanning analysis to detect recombination amongst both closely related, and widely divergent strains of RHDV. We show that recombination occurs commonly and in several different regions of the RHDV genome. Moreover, the first identified strain of RHDV, i.e. from China in 1984, showed evidence of recombination in the capsid gene, with a virus or viruses containing lineages in German strains. These observations imply that recombination may play a significant role in the evolution, epidemiology and diversity of RHDV.

Detection of positive selection in the major capsid protein VP60 of the rabbit haemorrhagic disease virus (RHDV)

“…The following strains were excluded from the analysis since they were shown to be recombinants (Abrantes et al, 2008;Forrester et al, 2008): Hartmannsdorf (GenBank accession number Y15425); Czech V351 (GenBank accession number U54983); Mexico (GenBank accession number AF295785); China 1984 (GenBank accession number AF402614) and France 00-08 (GenBank accession number AJ319594). No evidence of recombination was found for the remaining strains used (data not shown).…”

“…Recently, recombination within the VP60 gene was described (Abrantes et al, 2008;Forrester et al, 2008). It is therefore possible that by analyzing only parts of the major capsid protein a number of recombinant strains go undetected in phylogenetic studies.…”

Diversity of RHD virus: epidemiological, diagnostic and immunological importance

“…Procesy rekombinacji genetycznej stwierdzono już u RHDV i RHDVa, ale skala zjawisk była ograniczona i nie miała decydującego wpływu na szeroką pojętą zmienność wirusa RHD (1,24,28). Znacznie większy udział mechanizmów rekombinacji lagowirusów wykazano, badając sekwencje kilkudziesięciu portugalskich szczepów RHDV z lat 1994-2014 (7,49).…”

Evaluation of the usefulness of laboratory diagnostic methods in RHD outbreak

“…Sporadic RHD cases have been described in North Africa (30), in Mexico (19), Cuba, the USA (10) and most recently in Canada (9). In Australia and New Zealand RHD was deliberately introduced in the mid-nineties in order to reduce the population of rabbits (8,14,15,16,36). Rabbit haemorrgahic disease virus (RHDV), a prototype of the genus Lagovirus of the Caliciviridae family, is the infectious agent responsible for RHD.…”