5. Evolution of hantaviruses
Numerically, the most common events in the genomic evolution of hantaviruses are single-nucleotide substitutions. Nucleotide insertions and deletions, including those leading to frameshift mutations, are important in the evolution of hantaviruses, particularly in the macroevolution (e.g., inter-species evolution) of hantaviruses.57
Like other viruses with multiple genomic segments, hantaviruses can utilize genomic recombination and reassortment to rapidly change their genomic sequences. Genomic reassortment and recombination events frequently occur in nature and have been demonstrated in in vitro experiments. These events have facilitated the adaptation of hantaviruses to multiple hosts and ecosystems.4,58
Recombination events in the S or M segment in OWHVs (e.g., HTNV, SEOV, ANDV, TULV, and PUUV) have been recorded.55,58 A recombinant HTNV strain A16 isolated from Shaanxi Province in China had a parent from a hantavirid species other than HTNV,55suggesting that recombinant events in hantaviruses can occur among different hantavirid species.