Incidence of human sapovirus outbreaks in Beijing, China, 2014–2021: predominance of genotypes GII.3 and GI.2

Figure 1.. The temporal distribution of the sapovirus outbreaks in Beijing, China between 2014 and 2021 The overall number of acute gastroenteritis outbreaks (total bars), sapovirus-associated outbreaks (blue segments), and the monthly proportion of sapovirus outbreaks (red dashed line) were shown. The x-axis indicates the surveillance timeline by month. The primary y-axis (left) represented the number of outbreaks and the secondary y-axis (right) showed the proportion of sapovirus outbreaks relative to the total outbreaks.

Figure 2.. Age distribution of cases in the sapovirus outbreak. Age distribution of cases in the sapovirus outbreak was shown, with the X-axis representing age (years) and the Y-axis representing the number of outbreaks.

Figure 3.. The genotype distribution of sapovirus outbreaks in Beijing, China between 2014 and 2021. The genotype distribution of sapovirus outbreaks in Beijing, China between 2014 and 2021 was shown, with the X-axis representing the year and the Y-axis representing the proportion of different sapovirus outbreaks.

Figure 4.. The phylogenetic tree of GI and GII sapoviruses in VP1 gene. (A) the phylogenetic tree of GI sapoviruses in the VP1 gene; (B) the phylogenetic tree of GII sapoviruses in the VP1 gene. The phylogenetic relationships were estimated by the Beast with the best model of HKY. The genotype, year, and strain sources were indicated with different colours of label. sapovirus strains detected in this study were marked with the label “BJ New” in the strain label.

Figure 5.. The diversity of GI.2 and GII.3 sapoviruses. The proportion and prevalence of different clades of GI.2 and GII.3 sapoviruses from 2014 to 2021 were shown, with the x-axis representing the year and the y-axis representing the proportion of different clades of sapoviruses in different years.

Figure 6.. Sequence homology among different clades of GI.2 and GII.3 sapovirus relative to their closest reference strains. (A) Sequence homology among sapovirus GI.2 clades 1 and 2 relative to their closest reference strains with Genbank accession number: MG515477.1. (B) Sequence homology among sapovirus GII.3 clades 1, 3, and 4 relative to their closest reference strains with Genbank accession number: LC790161.1. (C) Sequence homology among sapovirus GII.3 clades 1, 3, and 4 relative to their closest reference strains with Genbank accession number: MN102405.1. The X-axis represents the position of nucleotide sequence and the y-axis represents the sequence similarity in different years.