Detection and molecular characterization of a pigeon variant of avian paramyxovirus type 1 virus (PPMV-1) from a blackbird (Turdus merula)

Cloacal and tracheal swabs taken from a dead blackbird (Turdus merula) were investigated as part of increased virological monitoring of wild birds during 2006, for the purpose of early detection of highly pathogenic avian influenza H5N1 virus. A pigeon variant of avian paramyxovirus type 1 virus (PPMV-1) was isolated by inoculation of the cloacal swab into the allantoic cavity of 10-day-old embryonated specific-pathogen-free chicken eggs. Molecular characterization of the isolate was performed by reverse transcription PCR and sequencing of the partial fusion (F) protein gene, including the region encoding the cleavage activation site of F protein. The PPMV-1 virus isolated from the blackbird shared the highest partial F gene nucleotide and amino acid sequence identity with PPMV-1 viruses isolated from the free-living and domestic pigeons in Slovenia between 2004 and 2006. The PPMV-1 strain isolated from the blackbird was classified, together with other PPMV-1 viruses associated with the ongoing panzootic in pigeons, into linage 4 sublineage 4b, group 4bii. The PPMV-1 virus isolated from the blackbird has a 112RRQKRF117 sequence, associated with virulent avian paramyxovirus type 1 viruses (Newcastle disease viruses), at the F protein cleavage site. To the best of our knowledge this is the first description of the detection of a PPMV-1 virus in a blackbird.