Influenza is a contagious viral disease that is seen in avian, human and other mammals, so its control is important. Vaccination against influenza virus subtype H9N2 is one of the ways in controlling program, for this reason several vaccines has been produced. Recently, application of inactivated oil-emulsion vaccines in poultry for controlling low pathogenic avian influenza is increasing. At p...

INTRODUCTION Given that influenza A(H9N2) is recognized as a pandemic threat, we evaluated the overall burden of influenza A(H9N2) infections among avian-exposed human populations. METHODS We performed a systematic search of PubMed, AGRICOLA, and CAB Abstracts databases for literature published during 1997-2013. Studies reporting serological evidence of human influenza A(H9N2) infection among...

Low pathogenic avian influenza (H9N2) is of major concern for the poultry industry especially in Iran, as the virus can spread rapidly in and between flocks, causing high mortality and severe economic losses. The aim of this study was to determine the pathogenicity of H9N2 avian influenza virus in thymus and bursa of Fabricius of commercial broiler chickens, so we studied the histologic lesions...

Avian influenza viruses are currently one of the main threats to human health in the world. Although there are some screening reports of antibodies against these viruses in humans from Western countries, most of these types of studies are conducted in poultry and market workers of Asian populations. The presence of antibodies against avian influenza viruses was evaluated in an elderly European ...

Since 1998, an epidemic of avian influenza occurred in the Iranian poultry industry. The identified agent was a low-pathogenicity H9N2 avian influenza virus that caused frequent episodes of high mortality in broiler chicken farms in Iran and some other Asian countries. This study was designed to investigate the prevalence of AIV H9N2 subtype in commercial chicken flocks in Dezful, southern Iran...

Sequence analysis and phylogenetic study of hemagglutinin (HA) gene of H9N2 subtype of avian influenza virus isolates (outbreaks of 1998-2002) in Tehran province (Iran) were studied. Two sets of forward and reverse primers in highly conserved regions, based on sequences of HA gene in Genbank, were designed. PCR products of a 430-bp fragment of 16 isolates were sequenced and then were aligned wi...

BACKGROUND Avian influenza viruses represent a growing threat of an influenza pandemic. The co-circulation of multiple H9N2 genotypes over the past decade has been replaced by one predominant genotype-G57 genotype, which displays a changed antigenicity and improved adaptability in chickens. Effective H9N2 subtype avian influenza virus vaccines for poultry are urgently needed. OBJECTIVE In thi...

the pb2 protein of influenza a viruses has been shown as host range determinant. in this study pb2gene of five h9n2 isolates from tehran province during the period of 1998-2001 were partially amplifiedand sequenced to do phylogenetic study. iranian isolates could be classified in eurasian lineage according totheir pb2 gene sequences. the pb2 genes of these isolates are different from those of m...

widespread occurrence of h9n2 low pathogenic avian influenza (lpai) viruses in many asian countriesduring the past decade has resulted in the need for evaluation of the pathogenesis of h9n2 virus infection. in this study, tissue tropism and dissemination of a/chicken/iran/772/1998(h9n2) virus throughout the body of broiler chickens were investigated. the clinical signs, gross lesions and antibo...

background: the h9n2 subtype of avian influenzaviruses (aivs) has been isolated in multiple avian species inmany european, asian, african and american countries. sincethe first outbreak of h9n2 virus in iran in 1998, this virus haswidely circulated throughout the country, resulting in majoreconomic losses in chicken flocks. several amino acids in thevirus ribonucleoprotein (rnp) complex includi...