most highly pathogenic avian influenza viruses (aiv) emerge after field passage of non-pathogenic aivs in birds. the outbreak of low-pathogenic h7n1 avian influenza virus in italy during 1999-2000 followed by outbreak of highly pathogenic h7n1 avian influenza virus is one example in this regard. this experiment has been designed to investigate the effect of pre-infection of birds with lpai on s...

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...

BACKGROUND The pandemic influenza A (H1N1) pdm09 virus, avian influenza A (H5N1) virus, and influenza A (H7N9) virus induced severe morbidity and mortality throughout the world. Previous studies suggested a close association between the interferon-induced transmembrane protein-3 (IFITM3) genetic variant rs12252 and influenza. Here, we explored the correlation between the rs12252 and influenza s...

We conducted clinic-based surveillance for influenza virus among cases with acute febrile illness at 9 medical clinics in south-central Cambodia during 2006-2009. Patients greater than or equal to 24 months old presenting with acute fever (> 38 degrees C) were enrolled. In late July 2009, the study identified its first case of pandemic H1N1 (pH1N1) influenza virus infection. The prevalence of p...

The circulation of influenza C viruses in Rio de Janeiro, Brazil, was studied when significant levels of antibodies were detected (56. 7%) with hemagglutination inhibition test, used as a standard methodology for influenza virus studies.

Influenza viruses are classified into three types: A, B, and C. The genomes of A- and B-type influenza viruses consist of eight RNA segments, whereas influenza C viruses only have seven RNAs. Both A and B influenza viruses contain two major surface glycoproteins: the hemagglutinin (HA) and the neuraminidase (NA). Influenza C viruses have only one major surface glycoprotein, HEF (hemagglutinin-e...

  Introduction: The preparation of seasonal influenza virus vaccines and especially its large-scale production requirement after the emergence or reemergence of a pandemic will need an alternative host cell system due to current suboptimal methods and the insufficiency of embryonated chicken eggs needed for producing them. In response to the vital and increasing demand for alternative means for ...

OBJECTIVES Rapid diagnosis of influenza in hospitalised patients is important to prevent the transmission of the infection in the hospital. This prospective observational cohort study was designed to determine the relationship between the clinical diagnosis of influenza made by the physician at admission and the presence of influenza virus in patients with respiratory tract infections. METHOD...

The influenza virus genes that confer efficient transmission of epidemic and pandemic strains in humans have not been identified. The rapid spread and severe disease caused by the 1918 influenza pandemic virus makes it an ideal virus to study the transmissibility of potentially pandemic influenza strains. Here, we used a series of human 1918-avian H1N1 influenza reassortant viruses to identify ...