Genome of a husavirus from Southern Brazil

New viruses of the Picornavirales order have been discovered with the increase in the number of sequences obtained by high-throughput sequencing, as well as human stool-associated RNA virus (husavirus [HuV]), found in human stool samples. However, there is much to be clarified about HuV. Its cellular host, evolutionary history, and other biological characteristics are still unknown. Therefore, samples collected from human beings and environmental samples in a watershed in Southern Brazil were processed for the metagenomic library. Upon metagenomic analysis, we identified a HuV (husavirus LMM_67754 OP019707) genome with 8,846 bp, which was reported for the first time in Southern Brazil. The new genome presents only 37% of nucleotide identity with Brazilian strains and more than 90% with genomes from China, Vietnam, Venezuela, and the Netherlands. The HuV phylogeny presents significant differences among genomes, probably because multiple introductions of the virus may have occurred. Many questions still need to be answered about HuV. Therefore, more sequences and studies on this virus are necessary to improve the comprehension of the unknown origin of Picornavirales.

Automated summary

New viruses of the Picornavirales order, including the human stool-associated RNA virus (husavirus [HuV]), have been discovered through high-throughput sequencing. However, there is still much unknown about HuV, such as its cellular host and evolutionary history. In this study, a HuV genome with 8,846 bp was identified for the first time in Southern Brazil, showing significant differences from Brazilian strains but high similarity with genomes from China, Vietnam, Venezuela, and the Netherlands. Further research and sequencing are necessary to improve our understanding of HuV and its unknown origin within the Picornavirales order.