Phylogenetic relationships among sandfly fever group viruses (Phlebovirus: Bunyaviridae) based on the small genome segment.

The phleboviruses are more diverse in terms of arthropod vectors and antigenic relationships than most other genera of arthropod-borne viruses. In this study, 30 sandfly fever group viruses from the Naples, Sicilian, Punta Toro, Icoaraci and Frijoles serocomplexes were sequenced. Phylogenetic analyses were performed based on the sequence of the open reading frame for the nucleoprotein (N) and non-structural (NSs) protein genes of the small (S) segment. The five resultant genotypic lineages correlated with the serological grouping and were similar to analysis of M segment sequences. The sequence identity for N and NSs genes within the Sicilian, Naples, Punta Toro, Icoaraci and Frijoles serocomplexes was determined. The results indicated that genetic divergence for the S segment is lower than that for the M segment, suggesting that the S segment is more stable during evolution.