Subtype B avian metapneumovirus was isolated from three unvaccinated commercial laying chicken flocks in Brazil, showing 100% nucleotide identity among themselves and 95.6% with the vaccine strain.
Observational (n=3)
The study confirms the circulation of wild-type subtype B avian metapneumovirus in Brazilian commercial chicken flocks.
Subtype B avian metapneumovirus (aMPV) was isolated and detected by reverse transcriptase-polymerase chain reaction (RT-PCR) in Brazilian commercial laying chicken flocks with no history of vaccination against aMPV and presenting respiratory signs and decreased egg production. RT-PCR results from samples from three affected flocks revealed that the three isolates were subtype B. Partial sequence analysis of the G glycoprotein gene confirmed that the samples belonged to subtype B and were not of the vaccine type. Comparison of nucleotide and amino acid sequences of the G gene of the three Brazilian aMPV samples with subtype B isolates from other countries revealed 95.1% to 96.1% identity. Nucleotide sequences showed 100% identity among the Brazilian subtype B samples and 95.6% identity with the subtype B vaccine strain used in Brazil. This work describes the circulation of subtype B aMPV in Brazil and discusses its importance in terms of disease epidemiology.
Chacón et al. (2007) conducted an observational in Avian metapneumovirus infection (n=3). Subtype B avian metapneumovirus (aMPV) infection was evaluated on Detection and molecular characterization of aMPV. Subtype B avian metapneumovirus was isolated from three unvaccinated commercial laying chicken flocks in Brazil, showing 100% nucleotide identity among themselves and 95.6% with the vaccine strain.