Jiang X, Matson D O, Velazquez F R, Calva J J, Zhong W M, Hu J, Ruiz-Palacios G M, Pickering L K
Center for Pediatric Research, Children's Hospital of The King's Daughters, Eastern Virginia Medical School, Norfolk 23510-1001, USA.
J Med Virol. 1995 Dec;47(4):309-16. doi: 10.1002/jmv.1890470404.
Two-hundred Mexican children monitored from birth to 2 years of age in a cohort study of diarrhea were tested for Norwalk virus (NV) and Norwalk-related virus infection. Blood was collected quarterly and tested by an enzyme immunoassay (EIA) using the recombinant NV (rNV) particles as antigen. Stool was collected weekly and tested by an EIA using hyperimmune anti-sera from animals immunized with rNV and a reverse transcription-polymerase chain reaction (RT-PCR) with primers in the RNA polymerase region of NV. A high prevalence of serum antibody to NV (85% at age 2 years) was found by the antibody EIA. In 54 stool specimens selected from children who developed a high titer of serum antibody to rNV, none was positive for NV by the antigen EIA, but 6 yielded products by the RT-PCR. One stool specimen (MX virus) yielded a 3.3 kb RT-PCR product from the 3' end of the viral genome. The MX virus cDNA has a genomic organization like other caliciviruses. Sequence comparison showed that MX virus shares 80% nucleic acid and 91% amino acid sequence identity with Snow Mountain agent (SMA), but only 62% and 60% identity, respectively, with NV in the RNA polymerase region, suggesting that MX virus is a SMA-like virus.
在一项针对腹泻的队列研究中，对200名从出生到2岁的墨西哥儿童进行了诺如病毒（NV）和诺如病毒相关病毒感染检测。每季度采集血液，使用重组NV（rNV）颗粒作为抗原，通过酶免疫测定（EIA）进行检测。每周采集粪便，使用用rNV免疫的动物的超免疫抗血清通过EIA进行检测，并使用位于NV RNA聚合酶区域的引物进行逆转录聚合酶链反应（RT-PCR）检测。通过抗体EIA发现，NV血清抗体的高流行率（2岁时为85%）。在从产生高滴度rNV血清抗体的儿童中选取的54份粪便标本中，通过抗原EIA检测，没有一份NV呈阳性，但有6份通过RT-PCR产生了产物。一份粪便标本（MX病毒）从病毒基因组的3'端产生了一个3.3 kb的RT-PCR产物。MX病毒cDNA具有与其他杯状病毒相似的基因组结构。序列比较表明MX病毒与雪山因子（SMA）的核酸序列同一性为80%，氨基酸序列同一性为91%，但在RNA聚合酶区域与NV的同一性分别仅为62%和60%，这表明MX病毒是一种类似SMA样的病毒。
