Incidence of viral hemorrhagic disease in wild rabbit populations in Spain

The current distribution and rate of spread of rabbit hemorrhagic disease (RHD) has been studied in Spain using interviews with hunters and conservationists and field surveys. The disease is currently present throughout Spain. A low rate of expansion (2-15 km per month), yet long distances between simultaneous outbreaks, suggests human-related transmission of RHD. The disease appears annually, mainly during spring (52.5 %) and winter (33.8 %). Most of the interviewees (63 %) indicated that the first outbreak of the disease caused greater mortalities than successive outbreaks. To investigate this, we estimated the mortality rate from RHD ot one locality, six years after the initial outbreak. The mortality rate was approximately 30 %, and lower than that estimated during the first outbreak of RHD (55-75 %). Few populations of rabbits (7.5 %) have returned to levels they held prior to the onset of the disease. Recovery was greater among dense populations. Most sites with low population of rabbits prior to the arrival of RHD have not recovered.