Phylogenetic analysis of avian paramyxovirus 1 strains isolated in Finland

Eight strains of avian paramyxovirus type 1 (PMV-1) isolated in Finland dur ing the last 3 decades were studied with reverse transcriptase polymerase c hain reaction (RT-PCR) and subsequent sequence analysis of the region of 20 8 nucleotides covering the fusion (F) protein cleavage site. Both genetic a nd antigenic heterogeneity of the strains was significant. Direct epidemiol ogical links between strains isolated during successive outbreaks, and also between strains isolated from wild fauna and from poultry or captive birds , were seen in this study. These results also support the previously publis hed view that wild waterfowl serve as a reservoir for the apathogenic or lo w-pathogenic strains, allowing them to evolve further into pathogenic strai ns.