Co-circulating genetically divergent A2 human metapneumovirus strains among children in southern Taiwan.
An outbreak of human metapneumovirus (hMPV) among children in southern Taiwan in 2004 prompted the investigation of the molecular epidemiology of hMPV from September 2003 to August 2005. Respiratory specimens that were culture negative for a panel of respiratory viruses were examined for the presence of hMPV by RT-PCR. The results indicated that 59 out of 546 (10.8%) children were hMPV-positive. The majority of these hMPV-positive children were less than 2 years old (59.4%), females (61%), and inpatients (67.8%). Infections occurred throughout the year, but peaked during the spring and/or summer months. Sequence analysis of the fusion gene from the isolates revealed two phylogenetic groups with five possible lineages (A1, A2a/A2b, B1, and B2). Among these co-circulating strains, A2 strains were most frequently observed and demonstrated the greatest divergence. Deduced amino acid sequence analysis identified several variant amino acids specific to the A2 lineage. Lineage-specific amino acid substitutions were noted at aa233, aa286, aa312, aa348, and aa296. This study indicated that genetically divergent strains of hMPV which caused respiratory disease and hospitalization were circulating among children in Taiwan.
Wang
Hsuan-Chen
HC
Division of Clinical Research, National Health Research Institutes, No. 137, Shengli Rd., Tainan, Taiwan.
Huang
Sheng-Wen
SW
Wang
Shainn-Wei
SW
Tsai
Huey-Pin
HP
Kiang
David
D
Wang
Shih-Min
SM
Liu
Ching-Chuan
CC
Su
Ih-Jen
IJ
Wang
Jen-Ren
JR
D019943:Amino Acid Substitution / Q000235:genetics; D002675:Child, Preschool; D005260:Female; D014644:Genetic Variation; D006801:Humans; D007223:Infant; D008297:Male; D029121:Metapneumovirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D018184:Paramyxoviridae Infections / Q000453:epidemiology* / Q000821:virology; D010802:Phylogeny; D013624:Taiwan / Q000453:epidemiology