Molecular epidemiology of rabbit haemorrhagic disease virus outbreaks in France during 1988 to 1995

In order to evaluate genetic variation between rabbit haemorrhagic disease virus (RHDV) isolates and to derive phylogenetic relationships, 56 virus isolates collected from various parts of France over a 7 year period (1988 to 1995) were examined. Analyses were carried out by direct nucleotide sequencing of PCR fragments of three genomic regions encoding the capsid protein (VP60) (regions A and B) and a non-structural protein (region C). Multiple sequence alignments revealed maximum nucleotide divergence of 7.6, 9.4 and 8.7% for regions A, B and C, respectively, indicating a high level of conservation between isolates. Irrespective of the genomic region analysed, phylogenetic analyses carried out using various methods allowed the identification of three genogroups; distribution of isolates within these genogroups appears to be more related to the year of their collection than to their geographical origin. The possible evolution of RHDV is discussed.