Abstract：
Torque teno virus (TTV) is considered to be an ubiquitous member of the commensal human blood virome commonly reported in mixed genotype co-infections. This study investigates the genomic diversity of TTV in blood samples from 816 febrile Tanzanian children. Metagenomic next-generation sequencing was used to screen for TTV in individual blood samples from a cohort of 816 febrile Tanzanian paediatric outpatients. For positive samples, the number of TTV species and genotypes present were evaluated. We investigate the linear relationship between individual TTV diversity and the patient age by linear regression. TTV was detected in 97.2% of sera. ORF1 analysis revealed the presence of 149 genotypes from 38 species, suggesting the presence of 13 new species. These genotypes were mostly present as co-infections with a median of 11 genotypes/subject (range: 1−71). In terms of species, we found a median of nine species/subject (range: 1−29). We further show a significant association between the diversity of co-detected TTV and the age of the subjects (p value < 0.0001). This study shows that significant TTV genomic diversity is acquired by the age of five and that this diversity tends to increase with age, which indicates a repetitive TTV acquisition during the first months/years of life.
摘要：
Torqueteno病毒（TTV）被认为是常见的人类血液病毒的普遍存在成员，通常在混合基因型共感染中报道。这项研究调查了来自816名发热坦桑尼亚儿童的血液样本中TTV的基因组多样性。宏基因组下一代测序用于筛选来自816名发热坦桑尼亚儿科门诊患者的个体血液样本中的TTV。对于阳性样本，评估了存在的TTV物种和基因型的数量。我们通过线性回归研究个体TTV多样性与患者年龄之间的线性关系。在97.2%的血清中检测到TTV。ORF1分析显示存在来自38个物种的149个基因型，表明存在13个新物种。这些基因型大多作为共感染存在,具有11个基因型/受试者的中值(范围:1-71)。就物种而言,我们发现中位数为9种/受试者(范围：1−29)。我们进一步显示了共同检测的TTV的多样性与受试者年龄之间的显著关联(p值<0.0001)。这项研究表明，显著的TTV基因组多样性是在五岁时获得的，并且这种多样性随着年龄的增长而增加。这表明在生命的头几个月/几年内重复获取TTV。
