Metagenomic detection and genetic characterization of human sapovirus among children in Nigeria
Using a metagenomic sequencing approach on stool samples from children with Acute Flaccid Paralysis (AFP), we describe the genetic diversity of Sapoviruses (SaVs) in children in Nigeria. We identified six near-complete genome sequences and two partial genome sequences. Multiple SaV genogroups and genotypes were detected, including GII (GII.4 and GII.8), GIV (GIV.1) and GI (GI.2 and GI.7). Sequence identity and phylogenetic analysis showed that the Nigerian SaVs were related to previously documented gastroenteritis outbreaks associated strains from China and Japan. Minor variations in the functional motifs of the nonstructural proteins NS3 and NS5 were confirmed in the Nigerian strains. To adequately understand the effect of such amino acid changes, a better understanding of the biological function of these proteins is vital. The identification of distinct SaVs reinforces the need for robust surveillance in acute gastroenteritis (AGE) and non-AGE cohorts to better understand SaVs genotype diversity, evolution, and its role in disease burden in Nigeria.