I. Characteristics of influenza A-turkey-Wisconsin-1966 virus. Cookies policy.
It is worth noting that interventions involving implementation of one or two rest days per month in the wholesale and retail LPMs could significantly reduce the H9N2 isolation rates [33]. By mid-February, all parts of the country were affected and the disease spread to layers and breeders farms, which showed very severe respiratory signs, mortality rates ranging from 2 to 15 %and drastic drop in egg production (up to 80 %) with no complete recovery after several weeks. In the RT-PCR, 95% of the birds were positive for one of the three viruses. The risk to UK residents travelling to China is very low. However, just such mild infection has made H9N2 easily be negligible in clinical, facilitating to adapt further in the body by reassortment with other human influenza viruses to yield potential variants with high reproductivity and even efficient interpersonal transmissibility. This video is unavailable. Cite this article. PubMed
In addition, the identified swine H9N2 isolates exhibited evident genetic and antigenic complexity with diversified genotypes [85]. Morocco just faced its first H9N2 influenza virus outbreaks early 2016 affecting different types of poultry production. However, those above mentioned AI viruses were all identified from apparently healthy birds, therefore insufficient to certify the actual existence of disease outbreaks. Limited shedding and lack of cage-mate transmission suggest that passerines are not significant reservoirs of LPAIV, although species differences apparently exist. This study suggests that the H5N1, H5N2, and H5N3 infections occurred at distinct sites in chicken and ducks, and that For this reason seroprevalence survey was carried out in two-hundred house, Waterfowl and shorebirds are well-recognized natural reservoirs of low-pathogenicity avian influenza viruses (LPAIV); however, little is known about the role of passerines in avian influenza virus ecology. Sci Rep 5:8262, Kamal RP, Kumar A, Davis CT, Tzeng WP, Nguyen T, Donis RO, Katz JM, York IA (2015) Emergence of highly pathogenic avian influenza A(H5N1) virus PB1-F2 variants and their virulence in BALB/c Mice. Poultry farms as a source of avian influenza A (H7N9) virus reassortment and human infection. A comparative study examining replication and disease pathogenesis associated with low-pathogenic H5N1, H5N2, or H5N3 avian Eleven samples from respiratory tissues collected from different cases and analysed by real time RT-PCR for the presence of Infectious bronchitis, Newcastle disease and virulent IBD viruses werenegative. PubMed Central All authors read and approved the final manuscript.
© 2020 BioMed Central Ltd unless otherwise stated. All content is available under the Open Government Licence v3.0, except where otherwise stated, National restrictions in England from 5 November, Risk Assessment of Avian Influenza A(H9N2), Avian influenza A (H7N9): Public Health England risk assessment, Avian influenza: epidemiological protocols, Avian influenza: guidance, data and analysis, Coronavirus (COVID-19): guidance and support, Transparency and freedom of information releases. 4, 10, 11, and 13: positive samples. However, most of the influenza B viruses were B/Beijing/184/93-like strain, but few of them were antigenically similar to B/Shandong/7/97 virus. Studies in experimentally infected birds suggest that clinical signs usually develop within a few days of virus shedding; however, some models and outbreak descriptions suggest that clinical signs may not become evident for a week or more in some H5 or H7 HPAI-infected flocks. The Study During 2004–2007, as part of a broader biodiversity survey and inventory program, we sampled birds from mostly forested sites in Guangxi and Guizhou Provinces in the southern part of the People’s Republic of China (Figure). Each color represents a specific virus subtype. 2000 Aug;19(2):493-508. doi: 10.20506/rst.19.2.1228. J Virol 77:3148–3156, Gou Y, Xie J, Wang M (2000) A strain of influenza A H9N2 virus repeatedly isolated from human population in China. Despite the fact that H9N2 is considered as low pathogenic virus, it has been reported that several microbial agents of the respiratory tract and some environmental factors exacerbate IAV H9N2 infections, leading to very severe respiratory disease and causing mortality up to 65 % in broiler chickens and up to 70 % drop in egg production in layers and breeders [12, 13]. Most cases showed very high decrease in feed consumption and very severe respiratory signs (sneezing, coughing, rales and gasping). None of the Moroccan isolates contained deletion at amino acid positions 80–84 in NS1. On the other hand, at present there is no evidence that geese and swans play a role in transmission of Newcastle disease, duck plague, West Nile virus, Vibrio, Yersinia, Clostridium, Chlamydophila, and Borrelia. Results of this study revealed that house sparrows showed ability to be infected with H9N2 avian influenza virus and play an important role in spreading of AIV as natural carriers. PCR products of the expected length were purified with the Nucleospin gel and PCR cleanup kit (Macherey Nagel) according to the manufacturer’s instructions. In this review, we mainly focused on the epidemiological dynamics, biological characteristics, molecular phylogeny and vaccine strategy of H9N2 subtype avian influenza virus in China to present an overview of the situation of H9N2 in China. The nucleotide sequences of Moroccan H9N2 viruses characterized in our study (with black circle shaped symbols) were compared with relevant virus sequences available in GenBank and GISAID databases. Infect Genet Evol 40:17–20, Octaviani CP, Goto H, Kawaoka Y (2011) Reassortment between seasonal H1N1 and pandemic (H1N1) 2009 influenza viruses is restricted by limited compatibility among polymerase subunits. Domestically, various H9N2 strains have been used for inactivated vaccine development, wherein the F strain and SS strain respectively belonging to genotype H and genotype A are the two typical representatives [63, 64]. 1), haemorrhagic lungs, pneumonia with fibrinous exudates and airsaculitis. to map the HA gene phylogeny through comparing more than 1000 HA sequences retrieved from GenBank, as referred to the nomenclature of the Asian H5N1 HPAIV defined by the WHO/OIE/FAO H5N1 working group [37, 38]. Le virus H9N2 est un sous-type faiblement pathogène de l’Influenza Aviaire. Seroconversion was detected as early as 3 days post inoculation (d.p.i.) As compared with genetic drift, gene reassortment poses a more radical effect on influenza virus by generating totally brand-new viruses with competitive advantage to spread widely such as those causing influenza pandemics in history [48,49,50,51]. Chickens usually seemed to be healthy after the infection but some of them do show depression and ruffled feathers. 2). Waterborne transmission from inoculated sparrows to contact Azizpour A, Goudarzi H, Charkhkar S, Momayez R, Hablolvarid MH. J.L.G. The virus spread in the early 2000s to several countries of the Middle East, including Israel, Saudi Arabia, United Arab Emirates and Sultanate of Oman [7–9]. Genotypic diversity of H9N2 subtype avian influenza viruses in China during 1996–2015. 2011;183:767–73. The Passeriformes are found in most parts of the world and cover a variety of habitats from rural to urban areas. Frequently used live virus vectors contain recombinant fowlpox virus, Newcastle disease virus, Marker’s disease virus, etc [74,75,76]. Arch Virol. 2005;340:70–83. The two antigenically and genetically distinguishable strains of influenza B virus were also still co-circulating in men in southern China. J Virol 86:11939, Zhong L, Wang X, Li Q, Liu D, Chen H, Zhao M, Gu X, He L, Liu X, Gu M, Peng D, Liu X (2014) Molecular mechanism of the airborne transmissibility of H9N2 avian influenza A viruses in chickens. A truncated 52 amino acids PB1-F2 protein was harbored by the 5 Moroccan isolates. 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Correspondence to Presently, H9N2 subtype AI virus has been widely spread in China, and has established stable lineages in commercial chicken flocks with endemicity [40]. titers from the oropharynx and cloaca, and infection was fatal. 2013;2:26. The HA of Moroccan H9N2 isolates analyzed in this study had a RSSR*GLF motif at the HA0 cleavage site, a characteristic of the LPAI viruses in poultry.
Privacy This study was carried out to find the role of house sparrows in the spread of low-pathogenicity avian influenza viruses as carrier birds.