A systematic review on wild animal infectious disease outbreaks following conservation translocation

Abstract

La translocación de animales silvestres se utiliza como estrategia para la conservación de poblaciones en declive. Sin embargo, las enfermedades emergentes son un riesgo durante la translocación que podrían afectar ecosistemas, el bienestar animal e intereses socioeconómicos. La vigilancia y el manejo de las enfermedades durante las translocaciones son importantes para maximizar la salud de los individuos y minimizar el riesgo de brotes de enfermedades. Se realizó una revisión sistemática de artículos científicos de investigación primaria sobre enfermedades infecciosas en tetrápodos salvajes durante o después de una translocación. La literatura revisada sugirió que Norteamérica es la región geográfica con más publicaciones sobre este tema. También reveló que los mamíferos recibieron más atención que otros taxones, por consecuente, el mayor número de brotes de enfermedades se dio en esta clase taxonómica. Los brotes de enfermedad fueron causados principalmente por agentes virales y parásitos de hospedadores múltiples. Además, más de la mitad de los brotes de enfermedades fueron causados por una enfermedad de peligro poblacional. Durante el análisis de riesgo de enfermedad se deben enfocar los esfuerzos en estas características de los parásitos, sin embargo, es necesario analizar caso por caso debido a la heterogeneidad de nuestros hallazgos.

During the last century, human population growth has impoverished biodiversity and wild animal populations are declining. This has pushed conservationist to translocate wild animals as a mitigation strategy and this trend will increase in the future. Translocations carry several risks that could affect ecosystems, animal welfare, and socioeconomic interests. One of these risks is the outbreak of diseases both in translocated animals and animals in the destination site, which compromises the translocation objectives. To maximize the health of organisms and to minimize the risk of disease outbreaks, the management and surveillance of diseases during translocations are important. Wild animal disease risk analysis tools had been proposed, however, they are a slow and uncertain process. Thus, this study aimed to better understand the origin of wild animal disease outbreaks following conservation translocations to focus efforts during the disease risk analysis and mitigation strategies. A systematic review was carried on covering primary research papers on infectious disease in wild tetrapods during or after conservation translocation. The literature reviewed suggested North America as the geographical region with more publications on this subject. The literature search also revealed that mammals received more attention than other taxa, therefore, the bigger number of disease outbreaks were also in this taxonomic class. The disease outbreaks across taxa were caused mainly by viral agents and multi-host parasites. Furthermore, more than half of the disease outbreaks found in this review were caused by a population hazard. Hence, the efforts during the disease risk analysis should be focused on parasites with these characteristics, nevertheless, it is necessary to analyze each translocation due to the heterogeneity of our findings. Information from future translocations should be standardized and uploaded into a common database to better understand the success and failures.