SEROEPIDEMIOLOGY OF RABBIT HEMORRHAGIC-DISEASE (RHD) IN WILD RABBITS (ORYCTOLAGUS-CUNICULUS) IN THE UNITED-KINGDOM

An extensive collection of blood samples from adult wild rabbits. from areas where Rabbit Haemorrhagic Disease (RHD) had not been recorded, was obtained from sites across the U.K, and parts of fire over the win ter of 1994/95. Sera from 946 animals were examined for antibodies to RHD. Antibody was found in all populations, varying between 20 and 100 % depending on locality, and overall 64% of rabbits were seropositive in midwinter. supporting the view that non-pathogenic RHD or RHD-like caliciviruses. which are not producing clinical disease, circulate wit hin rabbit populations. The serological response to these agents appea rs to confer significant immunity on rabbits subsequently exposed to t he virulent RHD virus, so the disease a will not be as devastating as myxomatosis was in the early 1950s (99% mortality) but at least one-th ird of the c. 40 million rabbits in the U.K. are susceptible.