Canine distemper virus (CDV) is one of the most significant infectious disease threats to the health and conservation of free-ranging and captive wild carnivores. CDV vaccination using recombinant canarypox-based vaccines has been recommended for maned wolf (Chrysocyon brachyurus) after the failure of modified live vaccines that induced disease in vaccinated animals. Here, we report a CDV outbreak in a captive population of maned wolves that were previously vaccinated. Five juveniles and one adult from a group of seven maned wolves housed in an outdoor exhibit died in April–May 2013 in a zoo in the Metropolitan Region, Chile. Clinical signs ranged from lethargy to digestive and respiratory signs. Diagnosis of CDV was confirmed by histopathology, antibody assays, and viral molecular detection and characterization. The phylogenetic analyses of the nucleotide sequence of the H gene of the CDV genome identified in the two positive samples suggest a close relation with the lineage Europe 1, commonly found in South America and Chile. CDV infections in maned wolves have not been previously characterized. To the authors’ best knowledge, this is the first report of the clinical presentation of CDV in a canine species previously immunized with a recombinant vaccine.

Canine morbillivirus, also known as canine distemper virus (CDV) is one of the most important infectious diseases threat to the health and conservation of free ranging and captive wild carnivores. CDV vaccination using recombinant vaccines has been recommended for maned wolf (Chrisosyon brachyurus) after the failure of modified live vaccines that induced disease in vaccinated animals. However, there has been a lack of systematic evaluation about the response of this preventive protocol in zoo carnivores due to ethical reasons that do not approve vaccination trials with challenge in that species. Here we report a CDV outbreak in a captive population of maned wolf with an index case that was previously vaccinated with a recombinant vaccine. Five juveniles and one adult from a group of seven maned wolves housed in an outdoor exhibit died in April-May 2013 in a zoo in the Metropolitan Region, Chile. Clinical signs ranged from lethargy to digestive and respiratory signs. Diagnosis of CDV was confirmed by histopathology, antibody assays and viral molecular detection and characterization. The phylogenetic analyses of the nucleotide sequence of H gene of the CDV genome identified in the two positive samples suggest a close relation with the lineage Europe 1, commonly found South America and Chile. CDV infections in maned wolf have not been previously characterized. To the authors best knowledge is the first report of the clinical presentation of CDV in a canine species previously inmmunized with a recombinant vaccine. Further research will be necessary to understand the impact of CDV in wild maned wolf populations and new protocols (with boosters) that could improve the effectiveness of the recombinant vaccine against CDV in wild carnivores. Transboundary and Emerging DiseasesCanine distemper outbreak by natural infection in a group of vaccinated maned wolves in captivity