objective: monitoring of influenza virus shedding and optimization of multiplicities of infection (moi) is important in the investigation of a virus one step growth cycle and for obtaining a high yield of virus in vaccine development and conventional basic diagnostic methods. however, eluted infectious viruses may still be present immediately after virus inoculation and when cells are washed fo...

News WHO recommendations on the composition of the 2017/18 influenza virus vaccines in the northern hemisphere Eurosurveillance editorial team ¹ On 2 March 2017, the World Health Organization (WHO) published recommendations on the composition of the trivalent and quadrivalent vaccines for the 2017/18 northern hemisphere influenza season [1]. WHO recommends that trivalent vaccines for use in the...

While infection with influenza A viruses has been extensively investigated, infections with influenza B viruses which are commonly categorized into the highly homologous Victoria and Yamagata lineages, are less studied, despite their considerable virulence. Here we used RT-PCR assays, hemagglutination inhibition assays and antibody titers to determine the levels of influenza B infection. We rep...

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...

Archival serum samples from elderly individuals with underlying chronic obstructive pulmonary disease (COPD) who were enrolled in a double-blind case-control study of seasonal influenza vaccine efficacy were assayed for cross-neutralizing antibody formation to avian influenza A (H5N1) virus. Of 118 serum samples, 58 were collected from influenza vaccinees (mean age 68.5 y), and 60 from placebo ...

Background: The H9N2 subtype of the influenza virus, which is endemic in many regions of Iran, is considered as a candidate for future pandemics. In the present study, excretion time of the Iranian endemic influenza virus (H9N2 subtype) from the feces and pharyngeal secretions of laying chicken breeds was evaluated. Methods: This experimental study conducted at the Diagnostic Laboratory Scienc...

For influenza A and B viruses to be infectious, they require eight viral RNA (vRNA) genome segments to be packaged into virions. For efficient packaging, influenza A viruses utilize cis-acting vRNA sequences, containing both non-coding and protein coding regions of each segment. Whether influenza B viruses have similar packaging signals is unknown. Here we show that coding regions at the 3' and...

conclusions taken together, these data reveal that cellular protease of chicken liver cells allows the replication of high yields of h9n2 virus in the absence of trypsin and also cell death in the infected cells is due to necrosis. results the degree of viability was significantly reduced in infected hepatoma cells. observations of caspase activation and cell dna laddering in infected cells wer...

Background and Aims: Influenza virus is a major pathogen involved in respiratory illnesses during winter seasons. A variety of diagnostic methods have been developed to identify influenza viruses in clinical specimen. Methods: Nasal and pharyngeal samples taken from patients were inoculated into Madin-Darby canine kidney (MOCK) cells and embryonated chicken eggs (ECEs). The culture media was a...

This study sought to define the role of memory lymphocytes in the protection from homologous influenza A virus re-challenge in rhesus macaques. Depleting monoclonal antibodies (mAb) were administered to the animals prior to their second experimental inoculation with a human seasonal influenza A virus strain. Treatment with either anti-CD8α or anti-CD20 mAbs prior to re-challenge had minimal eff...