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ABSTRACT: Budgerigar fledgling disease (BFD) and psittacine beak and feather disease (PBFD) are caused by avian polyomavirus (APV) and psittacine beak and feather disease virus (PBFDV), respectively. These diseases frequently infect psittacine birds and result in similar clinical manifestations. In this study, we observed the prevalence of PBFDV infection and a dual infection of APV and PBFDV in a budgerigar (Melopsittacus undulatus) in Mainland China for the first time. One PBFDV isolate and two APV isolates were harvested using chicken embryos. Genetic characterization and phylogenetic analysis of the complete genome of the two APV isolates revealed nucleotide similarity ranging from 99.0% to 99.6% to other sequences in GenBank, and a 14-bp insertion was observed in the genome of one APV isolate. The results of complete genome analysis of the PBFDV isolate showed nucleotide similarity ranging from 83.0% to 95.0% with other PBFDV sequences in GenBank. Genetic characterization and phylogenetic analysis of the APV and PBFDV strains isolated in this study indicated that the isolates from China were closely related to their Japanese counterparts. The results of this study will help to identify molecular determinants and will aid further research on the prevention and control of APV and PBFD infection.
Archives of Virology 01/2012; 157(1):53-61. · 2.11 Impact Factor
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ABSTRACT: H9 subtype avian influenza viruses (AIVs) are of significance in poultry and public health, but epidemiological studies about the viruses are scarce. In this study, phylogenetic relationships of the viruses were analyzed based on 1233 previously reported sequences and 745 novel sequences of the viral hemagglutinin gene. The novel sequences were obtained through large-scale surveys conducted in 2008-2011 in China. The results revealed distinct distributions of H9 subtype AIVs in different hosts, sites and regions in China and in the world: (1) the dominant lineage of H9 subtype AIVs in China in recent years is lineage h9.4.2.5 represented by A/chicken/Guangxi/55/2005; (2) the newly emerging lineage h9.4.2.6, represented by A/chicken/Guangdong/FZH/2011, has also become prevalent in China; (3) lineages h9.3.3, h9.4.1 and h9.4.2, represented by A/duck/Hokkaido/26/99, A/quail/Hong Kong/G1/97 and A/chicken/Hong Kong/G9/97, respectively, have become globally dominant in recent years; (4) lineages h9.4.1 and h9.4.2 are likely of more risk to public health than others; (5) different lineages have different transmission features and host tropisms. This study also provided novel experimental data which indicated that the Leu-234 (H9 numbering) motif in the viral hemagglutinin gene is an important but not unique determinant in receptor-binding preference. This report provides a detailed and updated panoramic view of the epidemiological distributions of H9 subtype AIVs globally and in China, and sheds new insights for the prevention of infection in poultry and preparedness for a potential pandemic caused by the viruses.
PLoS ONE 01/2012; 7(12):e52671. · 4.09 Impact Factor
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ABSTRACT: The novel influenza A(H1N1) virus that emerged recently in Mexico has spread rapidly to many countries and initiated a human pandemic. It would be interesting to determine whether the virus has existed in, or will spread to, the swine population. However, it is difficult to differentiate the virus from some swine influenza viruses. In this study, a SYBR Green I real-time RT-PCR assay was designed for detection and differentiation of influenza A(H1N1) virus from some swine influenza viruses, by comparing the amplification of two pairs of primers corresponding to influenza A(H1N1) virus and some swine influenza viruses, respectively. The assay was evaluated using online analysis, identified influenza viruses and clinical samples. The results indicated that the assay has high sensitivity and specificity to detect influenza A(H1N1) virus, and is able to differentiate it from some swine influenza viruses. This, in turn, could provide essential epidemiological information for risk analysis and decision making in combating the disease, and stimulate research to differentiate pathogens similar to each other using the same method.
Journal of virological methods 09/2009; 162(1-2):184-7. · 2.13 Impact Factor
