Agapov Eugene, Sumino Kaharu C, Gaudreault-Keener Monique, Storch Gregory A, Holtzman Michael J
Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA.
J Infect Dis. 2006 Feb 1;193(3):396-403. doi: 10.1086/499310. Epub 2005 Dec 28.
Human metapneumovirus (hMPV) was identified in 2001 as a cause of acute respiratory illness, but its characteristics are still being defined. We analyzed 3740 nasopharyngeal-wash specimens obtained during 2002-2004, using assays for common respiratory viruses and real-time polymerase chain reaction for hMPV. We detected hMPV in 5% of all specimens, compared with 28% for other respiratory viruses. Nucleotide sequence analysis of hMPV isolates revealed the predominant circulation of hMPV genotype A in the 2003 season but a switch to predominantly genotype B in 2004. Sequence analysis also revealed major differences in the hMPV G and SH genes but relative conservation of the F and N genes within each genotype. Phylogenetic analysis indicated a seasonal switch within hMPV genotype A subtypes as well. Despite genetic variability, we found no difference in the severity of illness caused by various hMPV isolates. These findings suggest that hMPV may vary in genetic structure, to allow for a seasonal shift in predominant genotype and the maintenance of infection rates.
人偏肺病毒（hMPV）于2001年被确认为急性呼吸道疾病的一个病因，但其特征仍在明确之中。我们分析了2002年至2004年期间采集的3740份鼻咽冲洗液标本，采用了针对常见呼吸道病毒的检测方法以及针对hMPV的实时聚合酶链反应。我们在所有标本的5%中检测到了hMPV，而其他呼吸道病毒的检出率为28%。对hMPV分离株的核苷酸序列分析显示，2003年季节hMPV基因型A占主导地位，但在2004年转变为主要是基因型B。序列分析还揭示了hMPV的G基因和SH基因存在重大差异，但每个基因型内的F基因和N基因相对保守。系统发育分析也表明hMPV基因型A亚型内也存在季节性转变。尽管存在基因变异性，但我们发现不同hMPV分离株引起的疾病严重程度并无差异。这些发现表明，hMPV的基因结构可能会有所不同，以允许优势基因型出现季节性转变并维持感染率。
