Analysis of Aichi virus and Saffold virus association with pediatric acute gastroenteritis

•A study involving paired case-control to illustrate the prevalence of SAFV and AiV.•AiV and SAFV in stools from children were more prevalent in controls than cases.•Estimated the viral loads of AiV and SAFV in stool samples from pediatric cases with diarrhea and healthy controls.•Provided the evidence of no association of SAFV and AiV in acute gastroenteritis in children.•Reported the major genotype of AiV and SAFV in China.

BackgroundAichi virus (AiV) and Saffold virus (SAFV) have been reported in children with acute gastroenteritis and respiratory disease worldwide; however, their causative role in acute gastroenteritis remains ambiguous.ObjectivesTo assess the clinical association of AiV and SAFV with acute gastroenteritis in the pediatric population.Study designA case-control study involving 461 paired stool samples from pediatric cases with diarrhea and healthy controls was conducted in China. Quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) was used to screen AiV and SAFV.ResultsIn the 461 paired samples, AiV and SAFV were more prevalent among asymptomatic children than children with acute gastroenteritis (0.87% vs. 0.43% and 2.8% vs. 1.5%, respectively), with no significant differences between groups (p = 0.142 and p = 0.478, respectively). Cox regression model analysis revealed no correlation between AiV (odds ratio, OR = 2.24; 95% confidence interval, CI, 0.76-6.54) or SAFV infection (OR = 1.36; 95% CI, 0.86-2.15) and diarrhea. High viral loads were found in both AiV- and SAFV-positive groups, with no significant difference in viral load between the groups (p = 0.507 and p = 0.677, respectively). No other known enteric pathogens were found in the AiV-positive samples but common in SAFV-positive cases. Phylogenetic analysis revealed that all 6 AiV subjects clustered with genotype B. All 7 SAFV-positive cases and 8 of 13 SAFV-positive controls were genotyped successfully; the genotypes identified included SAFV-1, SAFV-2 SAFV-3, and SAFV-6.ConclusionOur study revealed no association of these viruses in acute gastroenteritis in children. These viruses may have the ability to replicate in humans; however, the infections are usually asymptomatic.