background upper respiratory tract infections (urti) in children are the most frequent reasons for visiting a family doctor, commonly resulting in inappropriate prescription of antibiotics. in underdeveloped countries, a viral respiratory tract infection may be followed by serious complications. more than 200 viral species are associated with respiratory tract diseases in humans and this number...

background and aims: the contribution genetic and antigenic diversity of h9n2 influenza viruses in evading from immune responses, cytotoxic t lymphocytes (ctl) epitopes in hemagglutinin (ha) protein restricted by hla binding peptides was identified. materials and methods: phylogenetic analyses were carried out for all of full length ha and deduced amino acid sequences of h9n2 viruses available ...

Avian influenza viruses (AIV) affect a wide range of birds and mammals, cause severe economic damage to the poultry industry, and pose a serious threat to humans. Highly pathogenic avian influenza viruses (HPAI) H5N1 were first identified in Southeast Asia in 1996 and spread to four continents over the following years. The viruses have caused high mortality in chickens and various bird species ...

Background: The H9N2 subtype of influenza A viruses is considered to be widespread in poultry industry. Adamantane is a group of antiviral agents which is effective both in prevention and treatment of influenza A virus infections. These drugs inhibit M2 protein ion channel which has role on viral replication. OBJECTIVES: The main objective of this study is to evaluate M gene of avian influenza ...

background and aims: vaccination is the most effective method to prevent influenza infection. among the available vaccines, cold-adapted live-virus vaccines are suitable approach that have been produced and evaluated for recent years in few countries. the goal of this project was to derivate a cold adapted variant of the influenza a/new caledonia/20/1999(h1n1). materials and methods: influenza ...

objective: survey of molecular characterization of nucleoprotein gene of h9n2 avian influenza viruses and determination of the genetic relationship of iranian h9n2 viruses and other asian viruses. materials and methods: the nucleoprotein (np) genes from 4 isolates of h9n2 viruses isolated from commercial chickens in iran during 2008-2009 were amplified by rt-pcr method and sequenced. nucleotid...

Avian influenza H9N2 subtype viruses have had a great impact on Iranian industrial poultry production economy since introduction in the country. To approach Rapid and precise identification of this viruses as control measures in poultry industry, a real time probe base assay was developed to directly detect a specific influenza virus of H9N2 subtype -instead of general detection of Influenza A ...

sixteen avian influenza (ai) h9n2 viruses were isolated from disease outbreaks in different parts of iranduring (1998–2001). these ai isolates were used for pathogenicity, haemagglutinin (ha) gene variation andphylogenetic analysis. results in both pathogenicity tests and ha gene cleavage site sequence detectionrepresented a non-highly pathogenic feature for all iranian ai isolates studied. the...