Factors influecing antibody prevalence against myxomatosis

Abstract

Myxomatosis is a viral disease that drastically decimated wild rabbit (Oryctolagus cuniculus) populations in Spain during the 50’s. This disease still affects the Spanish rabbit populations, although its incidence at large scale is poorly understood. The main goal of this study was to characterize myxomatosis in relation to the immunological status of rabbit populations distributed throughout Spain. Antibodies against the myxoma virus were determined using an immunoassay (ELISA) to a total of 753 rabbits sampled between 2003 and 2009 in 45 different locations. The effect of several variables, including animal age, rabbit abundance, and genetic differentiation of rabbit population (there are two different subspecies of rabbits in Spain), on the antibody prevalence against myxomatosis was tested using a GLM. Over half (52%) of the samples presented protective antibodies. Moreover, the proportion of juveniles and population abundance were identified to be the most important factors influencing the antibody prevalence against myxomatosis (negative and positive effect, respectively). GLM analysis did not found a genetic effect on the prevalence of antibodies. These results reinforce the observation that myxomatosis is an endemic disease in Spain, and call for the need of a higher number of epidemiological studies that identify the different types of immunoglobulins to confirm whether the loss of maternal antibodies found in this study is real or not. Finally, these finding suggests that prevalence of antibodies of hunted rabbits and a simple analysis of abundance, may be a useful surveillance protocol to predict the effect of myxomatosis in Spain.