BACKGROUND. The world is facing a novel H1N1 influenza pandemic. A pandemic scare with a similar influenza virus in 1976 resulted in the vaccination of nearly 45 million persons. We hypothesized that prior receipt of the 1976 "swine flu" vaccine would enhance immune responses to the 2009 novel H1N1 influenza strain. METHODS. A prospective, volunteer sample of employees aged > or = 55 years at a...

background: a new pandemic influenza a (h1n1) emerged in april 2009, causing considerable morbidity and mortality. since mutations in the haemagglutinin (ha) may influence the antigenicity and pathogenicity of the virus, continued epidemiological and molecular characterization for the effective control of pandemic flu and developing of more appropriate vaccine is crucial. objective: to monitor ...

BACKGROUND The population-based impact of infection with swine origin influenza A (H1N1) virus infection was not clear in the early days of the epidemic towards the end of May 2009. Australia had seven confirmed cases by 22 May 2009. We aimed to compare available data on swine origin influenza A (H1N1) virus infection overseas with seasonal influenza A (H1N1) virus infection in Australia to ass...

BACKGROUND A novel 2009 swine-origin influenza A H1N1 virus (S-OIV H1N1) has been transmitted among humans worldwide. However, the pathogenesis of this virus in human airway epithelial cells and mammals is not well understood. METHODOLOGY/PRINCIPAL FINDING In this study, we showed that a 2009 A (H1N1) influenza virus strain, A/Beijing/501/2009, isolated from a human patient, caused typical in...

To estimate effectiveness of seasonal trivalent and monovalent influenza vaccines against pandemic influenza A (H1N1) 2009 virus, we conducted a test-negative case-control study in Victoria, Australia, in 2010. Patients seen for influenza-like illness by general practitioners in a sentinel surveillance network during 2010 were tested for influenza; vaccination status was recorded. Case-patients...

results: of 655 samples, 69 (10.53%) had positive results for human influenza a virus, and 5 (0.7%) samples had positive results for influenza b. of those 69 samples with positive results for influenza a viruses, 45 (6.8%) were h3n2, and 24 (3.6%) were h1n1 subtypes. in this study most cases with positive results were less than 20 years. the sample positive included 49% males and 51% females. t...

The emergence of the pandemic 2009 H1N1 influenza A virus in humans and subsequent discovery that it was of swine influenza virus lineages raised concern over the safety of pork. Pigs experimentally infected with pandemic 2009 H1N1 influenza A virus developed respiratory disease; however, there was no evidence for systemic disease to suggest that pork from pigs infected with H1N1 influenza woul...

Influenza A (H1N1) viruses of swine origin were introduced into the human population in 2009 and caused a pandemic. The disease burden in the elderly was relatively low, which was attributed to the presence of cross-reacting serum antibodies in this age group, which were raised against seasonal influenza A (H1N1) viruses that circulated before 1957. It has also been described how infection with...

background and aims: influenza a viruses are important pathogens for humans especially in pandemic episodes. two adamantane derivates, amantadine and rimantadine, are used for prophylaxis and treatment of influenza a virus infections. however, single amino acid substitutions in the m2 transmembrane domain which lead to amantadine resistance of these viruses occur at residues 26, 27, 30, 31 or 3...