Molecular epidemiology of European brown hare syndrome virus in France between 1989 and 2003

Genetic diversity between French European brown hare syndrome (EBHS) viruses since the disease appeared has been evaluated. Nucleotide sequencing of the partial capsid protein genes of 169 EBHS viruses collected from various parts of France between 1989 and 2003, three reference strains, and a Greek EBHSV collected in 2002 revealed a maximum nucleotide divergence of 11.7%, indicating a high level of conservation between viruses. Two major groups were identified. The first group contained EBHS viruses collected since 1989 from different parts of France, the reference strains, and all of the viruses located in the far north of France. In this group, three genogroups were clearly identified as mainly related to their geographic origin. The distribution of the viruses suggests that the early viruses have not disappeared and have slowly evolved in their area of origin. The second group, supported by a significant bootstrap value, contained the Greek EBHSV with the French EBHS viruses collected between 1999 and 2003 from regions of southern France. It constitutes a newly identified genogroup. Our results demonstrate strong differences in genetic evolution between EBHSV and rabbit haemorrhagic disease virus, with persistence of the earlier EBHS viruses and interaction between the geographical and temporal distributions.