Bates Matthew, Monze Mwaka, Bima Humphrey, Kapambwe Mirriam, Clark David, Kasolo Francis C, Gompels Ursula A
Pathogen Molecular Biology Unit, Department of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, University of London, London, United Kingdom.
J Med Virol. 2009 May;81(5):779-89. doi: 10.1002/jmv.21455.
Human herpesvirus 6, HHV-6, commonly infects children, causing febrile illness and can cause more severe pathology, especially in an immune compromised setting. There are virulence distinctions between variants HHV-6A and B, with evidence for increased severity and neurotropism for HHV-6A. While HHV-6B is the predominant infant infection in USA, Europe and Japan, HHV-6A appears rare. Here HHV-6 prevalence, loads and variant genotypes, in asymptomatic compared to symptomatic infants were investigated from an African region with endemic HIV-1/AIDS. DNA was extracted from blood or sera from asymptomatic infants at 6 and 18 months age in a population-based micronutrient study, and from symptomatic infants hospitalised for febrile disease. DNA was screened by qualitative and quantitative real-time PCR, then genotyped by sequencing at variable loci, U46 (gN) and U47 (gO). HIV-1 serostatus of infants and mothers were also determined. HHV-6 DNA prevalence rose from 15% to 22% (80/371) by 18 months. At 6 months, infants born to HIV-1 positive mothers had lower HHV-6 prevalence (11%, 6/53), but higher HCMV prevalence (25%, 17/67). HHV-6 positive febrile hospitalized infants had higher HIV-1, 57% (4/7), compared to asymptomatic infants, 3% (2/74). HHV-6A was detected exclusively in 86% (48/56) of asymptomatic HHV-6 positive samples genotyped. Co-infections with both strain variants were linked with higher viral loads and found in 13% (7/56) asymptomatic infants and 43% (3/7) HIV-1 positive febrile infants. Overall, the results show HHV-6A as the predominant variant significantly associated with viremic infant-infections in this African population, distinct from other global cohorts, suggesting emergent infections elsewhere.
人类疱疹病毒6型（HHV - 6）通常感染儿童，引发发热性疾病，并且在免疫功能低下的情况下可能导致更严重的病变。HHV - 6A和B变体之间存在毒力差异，有证据表明HHV - 6A的严重程度增加且具有嗜神经性。虽然HHV - 6B是美国、欧洲和日本婴儿感染的主要类型，但HHV - 6A似乎较为罕见。在此，我们对非洲一个HIV - 1/艾滋病流行地区无症状和有症状婴儿的HHV - 6患病率、病毒载量及变体基因型进行了调查。在一项基于人群的微量营养素研究中，从6个月和18个月大的无症状婴儿的血液或血清中提取DNA，以及从因发热性疾病住院的有症状婴儿中提取DNA。通过定性和定量实时PCR对DNA进行筛查，然后在可变位点U46（gN）和U47（gO）进行测序以确定基因型。还确定了婴儿及其母亲的HIV - 1血清学状态。到18个月时，HHV - 6 DNA患病率从15%升至22%（80/371）。6个月时，HIV - 1阳性母亲所生婴儿的HHV - 6患病率较低（11%，6/53），但HCMV患病率较高（25%，17/67）。与无症状婴儿（3%，2/74）相比，HHV - 6阳性的发热住院婴儿的HIV - 1感染率更高，为57%（4/7）。在进行基因分型的无症状HHV - 6阳性样本中，86%（48/56）仅检测到HHV - 6A。两种毒株变体的共同感染与更高的病毒载量相关，在13%（7/56）的无症状婴儿和43%（3/7）的HIV - 1阳性发热婴儿中发现。总体而言，结果表明HHV - 6A是该非洲人群中与病毒血症婴儿感染显著相关的主要变体，与其他全球队列不同，这表明在其他地方也出现了感染情况。
