Kabue Jean Pierre, Meader Emma, Hunter Paul R, Potgieter Natasha
Department of Microbiology, School of Mathematical and Natural Sciences, University of Venda, Thohoyandou, RSA, South Africa.
School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, UK.
J Clin Virol. 2016 Nov;84:12-18. doi: 10.1016/j.jcv.2016.09.005. Epub 2016 Sep 13.
Human Norovirus (NoV) is recognized as a major etiological agent of sporadic acute gastroenteritis worldwide.
This study describes the clinical features associated with Human NoV occurrence in children and determines the prevalence and estimated viral burden of NoV in symptomatic and asymptomatic children in rural South Africa.
Between July 2014 and April 2015, outpatient children under 5 years of age from rural communities of Vhembe district, South Africa, were enrolled for the study. A total of 303 stool specimens were collected from those with diarrhea (n=253) and without (n=50) diarrhea. NoVs were identified using real-time one-step RT-PCR.
One hundred and four (41.1%) NoVs were detected (62[59.6%] GII, 16[15.4%] GI, and 26[25%] mixed GI/GII) in cases and 18 (36%) including 9(50%) GII, 2(11.1%) GI and 7(38.9%) mixed GI/GII in controls. NoV detection rates in symptomatic and asymptomatic children (OR=1.24; 95% CI 0.66⿿2.33) were not significantly different. Comparison of the median C values for NoV in symptomatic and asymptomatic children revealed significant statistical difference of estimated GII viral load from both groups, with a much higher viral burden in symptomatic children.
Though not proven predictive of diarrhea disease in this study, the high detection rate of NoV reflects the substantial exposure of children from rural communities to enteric pathogens possibly due to poor sanitation and hygiene practices. The results suggest that the difference between asymptomatic and symptomatic children with NoV may be at the level of the viral load of NoV genogroups involved.
人诺如病毒（NoV）被认为是全球散发性急性胃肠炎的主要病原体。
本研究描述了儿童感染人诺如病毒的临床特征，并确定了南非农村有症状和无症状儿童中诺如病毒的流行率及估计病毒载量。
2014年7月至2015年4月，来自南非万贝区农村社区的5岁以下门诊儿童被纳入研究。共收集了303份粪便标本，其中腹泻儿童（n = 253）和无腹泻儿童（n = 50）各151份。采用实时一步法逆转录聚合酶链反应（RT-PCR）鉴定诺如病毒。
病例组中检测到104例（41.1%）诺如病毒（62例[59.6%]为GII型，16例[15.4%]为GI型，26例[25%]为GI/GII混合型），对照组中检测到18例（36%），包括9例（50%）GII型，2例（11.1%）GI型和7例（38.9%）GI/GII混合型。有症状和无症状儿童的诺如病毒检出率（OR = 1.24；95%可信区间0.66⿿2.33）无显著差异。有症状和无症状儿童诺如病毒的C值中位数比较显示，两组估计的GII型病毒载量有显著统计学差异，有症状儿童的病毒载量更高。
尽管本研究未证实诺如病毒可预测腹泻病，但诺如病毒的高检出率反映了农村社区儿童可能因卫生条件差和卫生习惯不良而大量接触肠道病原体。结果表明，有症状和无症状诺如病毒感染儿童之间的差异可能在于所涉及的诺如病毒基因组的病毒载量水平。
