Phylogenetic analysis based on the complete HN gene nucleotide sequence of the different HPIV-2 strains circulating globally. Tree was constructed using Megalign program of Lasergene software (DNASTAR) with 1000 bootstraps. HPIV-2 strains included in the analysis were grouped in four clusters (G1-4). Each of clusters G1 and G4 were split into two subclusters (a and b). Riyadh 105/2009 strain was indicated by a red frame, and was grouped with Oklahoma-94-2009 strain in cluster G3. Scale bar indicates number of nucleotide substitution per site.