Avian Metapneumovirus Subgroup Research Articles

Sequence analysis of the large polymerase (L) protein of the US strain of avian metapneumovirus indicates a close resemblance to that of the human metapneumovirus

The complete nucleotide sequence of the large polymerase (L) protein of the avian metapneumovirus subgroup C strain Colorado was determined. The L protein gene of avian pneumovirus Colorado isolate (APV-C) was 6173 nucleotides in length from the gene-start to the gene-end and encoded a polypeptide of 2005 amino acids in length. The length of the L protein of APV-C was exactly the same as that of human metapneumovirus (hMPV) and one amino acid longer than the L protein of APV subgroup A. The L protein of APV-C showed 80% amino acid identity with the L protein of hMPV, but only 64% amino acid identity with the L protein of APV-A. The nucleotide and deduced amino acid sequences were compared with the corresponding sequences of eleven other paramyxoviruses. All six domains characteristic of paramyxovirus L proteins were also observed in the L protein of APV-C. All the polymerase core motifs in domain III were conserved to nearly 100% in the metapneumoviruses. Similarly, the putative ATP-binding motif in domain VI was completely conserved among the metapneumoviruses and differed in length, by one intermediate residue, from other paramyxoviruses. Phylogenetic analysis of the different L proteins also revealed a closer relationship between APV-C and hMPV.

Presence of the new human metapneumovirus in French children with bronchiolitis

We developed a polymerase chain reaction (PCR) to detect human metapneumovirus (hMPV) in French children hospitalized for acute respiratory tract disease during the winter of 2001 to 2002. This assay showed that 19 (6.6%) of 337 respiratory specimens that were negative for other respiratory viruses were positive for hMPV. Seven hMPV infections were also detected in the previous winter. The patients had the following clinical syndromes: bronchiolitis, 16; acute exacerbation of asthma, 4; bronchitis, 1; laryngitis, 1; high fever with diarrhea, 2; high fever with rhinopharyngitis, 1; rhinopharyngitis with conjunctivitis and otitis, 1. The sequences of the seven amplified products were similar for all cases and had 99% homology with the previously described N gene sequence.