Avian influenza viruses (AIVs) are single-stranded RNA viruses belonging to the Influenza virus A genus of the Orthomyxoviridae family. The segmented genome encodes ten or 11 proteins, depending on the strain. These proteins are the prominent outer surface glycoproteins HA and neuraminidase (NA), the matrix (M2) ion channels, the matrix (M1) protein, which is found lining the inner side of the ...

An experimental inactivated oil-emulsion H9N2 avian influenza vaccine was formulated with 3 parts ofinactivated avian influenza antigen A/Chicken/Iran/101/1998(H9N2) emulsified in 7 parts of oil adjuvant.Twelve week-old specific pathogen-free (SPF) chickens were divided into seven groups of 10 birds. Sixgroups were vaccinated with 1, 1/10th, 1/50th, 1/100th, 1/200th and 1/400th field dose of th...

BACKGROUND European starlings (Sturnus vulgaris) are common, widely distributed birds in North America that frequently come into contact with agricultural operations. However, starlings have been one of the neglected land-based wild bird species for influenza surveillance. OBJECTIVES To study the potential role of starlings in the ecology and epidemiology of influenza virus. METHODS We coll...

Seventeen avian species and two mammalian species were intranasally inoculated with the zoonotic A/chicken/Hong Kong/220/97 (chicken/HK) (H5N1) avian influenza (AI) virus in order to ascertain a relative range of susceptible hosts and the pathobiology of the resultant disease. A direct association was demonstrated between viral replication and the severity of disease, with four general gradatio...

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...

The current definitions of high-pathogenicity avian influenza (HPAI), formulated over 10 years ago, were aimed at including viruses that were overtly virulent in in vivo tests and those that had the potential to become virulent. At that time the only virus known to have mutated to virulence was the one responsible for the 1983-84 Pennsylvania epizootic. The mechanism involved has not been seen ...

in this study, the pathogenicity of a/ch/it/5093/1999 h7n1 which had been isolated from chicken during the outbreak in italy was assessed in chicken by experimental infection virus. ten spf chickens of four week-old were inoculated with this virus, and five chickens were inoculated with uninfected allantoic fluid. for determination of virus shedding, oropharyngeal and cloacal swabs were taken f...

influenza is one of the most important viral diseases that is common among the birds and the mammalsand is caused by specific viruses that belong to the orthomyxoviridae family. migratory aquatic birds arethe reservoir of the disease and there is a likelihood of the disease in any region. there are differentmethods for detecting the avian influenza, but by the point of detection rates, the elis...