Canine distemper outbreak in raccoons suggests pathogen interspecies transmission amongst alien and native carnivores in urban areas from Germany

- Large mortality outbreak amongst raccoons in Berlin, Germany.
- We confirm canine distemper virus (CDV) infection in 74 raccoons.
- We performed phylogenetic analyses of the CDV H-gene in raccoon-derived isolates.
- Our isolates clustered within the “Europe lineage” close to European foxes and dogs.
- Results indicate CDV transmission amongst raccoon and fox in urban areas.

From December 2012 to May 2013, an outbreak occurred among urban wild carnivores from Berlin. We collected 97 free-ranging raccoons from the city area. PCR assays, histopathology and immunohistochemistry confirmed canine distemper virus (CDV) infection in 74 raccoons. Phylogenetic analysis of haemagglutinin gene fragments (1767 nucleotides) of CDV isolated from four raccoons showed close relation to CDV isolates from foxes from Germany and a domestic dog from Hungary; all belonging to the “Europe” lineage of CDV. These study results suggest an inter-species transmission of CDV as the origin for the outbreak among the raccoon population. Implications for domestic pets and suggested interspecies transmission between urban wildlife and raccoons are discussed. This is the first major outbreak of CDV amongst free-ranging raccoons in Europe.