Division of Molecular Virology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
PLoS One. 2013 Jul 19;8(7):e69557. doi: 10.1371/journal.pone.0069557. Print 2013.
Norovirus (NoV) constitutes the second most common viral pathogen causing pediatric diarrhea after rotavirus. In Africa, diarrhea is a major health problem in children, and yet few studies have been performed regarding NoV. The association of histo-blood group antigens (HBGA) and susceptibility to NoV infection is well established in Caucasian populations with non-secretors being resistant to many common NoV strains. No study regarding HBGA and NoV susceptibility has yet been performed in Africa. We collected 309 stool and 208 saliva samples from diarrheal children in Ouagadougou, Burkina Faso; May 2009 to March 2010. NoV was detected using real-time PCR, and genotyped by sequencing. Saliva samples were ABO, Lewis and secretor phenotyped using in house ELISA assays. NoV was detected in 12% (n = 37) of the samples. The genotype diversity was unusually large; overall the 37 positive samples belonged to 14 genotypes. Only children <2 years of age were NoV positive and the GII.4 NoVs were more frequent in the late dry season (Jan-May). NoV infections were observed less in children with the secretor-negative phenotype or blood group A (OR 0.18; p = 0.012 and OR 0.31; p = 0.054; respectively), with two non-secretors infected with genotypes GII.7 and GII.4 respectively. Lewis-negative (Le(a-b-)) children, representing 32% of the study population, were susceptible to GII, but were not infected with any NoV GI. GII.4 strains preferentially infected children with blood group B whereas secretor-positive children with blood group O were infected with the largest variety of genotypes. This is the first study identifying host genetic factors associated with susceptibility to NoV in an African population, and suggests that while the non-secretor phenotype provides protection; the Lewis b antigen is not necessary for GII infection.
诺如病毒（NoV）是继轮状病毒之后导致儿童腹泻的第二大常见病毒病原体。在非洲，腹泻是儿童的一个主要健康问题，但针对 NoV 的研究很少。组织血型抗原（HBGA）与 NoV 易感性之间的关联在白种人群中得到了很好的证实，非分泌者对许多常见的 NoV 株具有抗性。在非洲，尚未进行关于 HBGA 和 NoV 易感性的研究。我们从布基纳法索瓦加杜古的腹泻儿童中收集了 309 份粪便和 208 份唾液样本；2009 年 5 月至 2010 年 3 月。使用实时 PCR 检测 NoV，并通过测序进行基因分型。使用内部 ELISA 检测唾液样本的 ABO、Lewis 和分泌型表型。在 12%（n=37）的样本中检测到 NoV。基因型多样性异常大；总体而言，37 个阳性样本属于 14 种基因型。只有<2 岁的儿童 NoV 阳性，GII.4 NoV 在旱季后期（1 月至 5 月）更为常见。在分泌型阴性或血型 A 的儿童中（OR 0.18；p=0.012 和 OR 0.31；p=0.054；分别），以及分别感染 GII.7 和 GII.4 的两个非分泌者中，观察到 NoV 感染较少。Lewis 阴性（Le(a-b-))儿童占研究人群的 32%，易感染 GII，但未感染任何 NoV GI。GII.4 株优先感染血型为 B 的儿童，而分泌型阳性的血型为 O 的儿童感染了最多样的基因型。这是首次在非洲人群中确定与 NoV 易感性相关的宿主遗传因素的研究，表明虽然非分泌者表型提供保护；但 Lewis b 抗原对于 GII 感染并非必需。
