Continuous circulation of influenza A(H5N1) virus among poultry in Egypt has created an epicenter in which the viruses evolve into newer subclades and continue to cause disease in humans. To detect influenza viruses in Egypt, since 2009 we have actively surveyed various regions and poultry production sectors. From August 2010 through January 2013, >11,000 swab samples were collected; 10% were p...

avian influenza is one of the most important diseases in avian industry, which also threats human population. thus, vaccination is necessary for controlling this viral disease. in this study, killed vaccine of avian influenza subtype h9n2 and formalin solution (for virus inactivation) were used. it is necessary to study the effect of different factors such as formalin concentration, as well as ...

background and aims: avian influenza (ai) h9n2 subtype was first reported to infect turkeys in the united states in 1966 and has been panzootic in eurasia. in iran, the h9n2 virus was first isolated from broiler chickens in 1998 in ghazvin province and it is the most prevalent subtype of influenza virus in poultry industry in iran at the present time. materials and methods: in this study, we se...

In China, H9N2 subtype avian influenza outbreak is firstly reported in Guangdong province in 1992. Subsequently, the disease spreads into vast majority regions nationwide and has currently become endemic there. Over vicennial genetic evolution, the viral pathogenicity and transmissibility have showed an increasing trend as year goes by, posing serious threat to poultry industry. In addition, H9...

A current view of the emergence of pandemic influenza viruses envisages a gene flow from the aquatic avian reservoir to humans via reassortment in pigs, the hypothetical "mixing vessel." Understanding arising from recent H5N1 influenza outbreaks in Hong Kong since 1997 and the isolation of avian H9N2 virus from humans raises alternative options for the emergence of a new pandemic virus. Here we...

In 2009, a novel H1N1 influenza (pH1N1) virus caused the first influenza pandemic in 40 y. The virus was identified as a triple reassortant between avian, swine, and human influenza viruses, highlighting the importance of reassortment in the generation of viruses with pandemic potential. Previously, we showed that a reassortant virus composed of wild-type avian H9N2 surface genes in a seasonal ...

To prevent H9N2 avian influenza virus infection in chickens, a long-term vaccination program using inactivated vaccines has been implemented in China. However, the protective efficacy of inactivated vaccines against antigenic drift variants is limited, and H9N2 influenza virus continues to circulate in vaccinated chicken flocks in China. Therefore, developing a cross-reactive vaccine to control...

backgrounds and objectives: classified as low pathogenic avian influenza (lpai) viruses, the h9n2 subtype causes severe respiratory disease in poultry farms and occasional respiratory disease in humans. in this study, the neuraminidase (na) gene of three avian influenza (ai) h9n2 strains isolated from poultry farms in iran during 2010-11, as well as other reported iranian h9n2 isolates, were ge...

H5N1 and H9N2 avian influenza virus subtypes top the World Health Organization's list for the greatest pandemic potential. Inactivated H5N1 vaccines induce limited immune responses and, in the case of live-attenuated influenza virus vaccines (LAIV), there are safety concerns regarding the possibility of reassortment between the H5 gene segment and circulating influenza viruses. In order to over...

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...