background and aims: canine distemper (cd) is a deadly infectious disease of canidae family. cd is a multi-systemic viral disease and is specified by wide range of clinical symptoms. the manifestations are not always indicative of cd, therefore a laboratory confirmation is necessary for suspected cases. materials and methods: different clinical specimens of 19 cd suspected unvaccinated dogs wer...

Influenza viruses infect vertebrates, including mammals and birds. Influenza virus reverse-genetics systems facilitate the study of the structure and function of viral factors. In contrast, less is known about host factors involved in the replication process. Here, we developed a replication and transcription system of the negative-strand RNA genome of the influenza virus in Saccharomyces cerev...

Influenza A viruses occur worldwide in wild birds and are occasionally associated with outbreaks in commercial chickens and turkeys. However, avian influenza viruses have not been isolated from wild birds or poultry in South America. A recent outbreak in chickens of H7N3 low pathogenic avian influenza (LPAI) occurred in Chile. One month later, after a sudden increase in deaths, H7N3 highly path...

The 1918 influenza A H1N1 virus caused the worst pandemic of influenza ever recorded. To better understand the pathogenesis and immunity to the 1918 pandemic virus, we generated recombinant influenza viruses possessing two to five genes of the 1918 influenza virus. Recombinant influenza viruses possessing the hemagglutinin (HA), neuraminidase (NA), matrix (M), nonstructural (NS), and nucleoprot...

Currently licensed vaccines against the influenza A virus (IAV) need to be updated annually to match the constantly evolving antigenicity of the influenza virus glycoproteins, hemagglutinin (HA), and neuramidiase (NA). Attempts to develop universal vaccines that provide broad protection have resulted in some success. Herein, we have shown that a replication-deficient adenovirus expressing H5/M2...

In 2007, we isolated a natural recombinant H9N2 avian influenza virus (AIV) from the fecal droppings of a white-fronted goose (Anser albifrons) in South Korea. Phylogenetic analyses of the complete genome sequence showed that polymerase acidic (PA) and neuraminidase (NA) genes belonged to the Eurasian lineage AIV, but polymerase basic 2 (PB2), PB1, hemagglutinin (HA), nucleoprotein (NP), matrix...

The detection of an antibody against nucleoprotein (NP) of the avian influenza virus (AIV) was attempted by an electrochemical immunoassay by combining a secondary antibody-alkaline phosphatase conjugate and 4-aminophenylphosphate. Released 4-aminophenol was quantitated electrochemically, and the current derived from oxidation of the hydrolysis product increased linearly over a wide primary ant...

BACKGROUND Alternative influenza vaccines and vaccine production forms are needed as the conventional protein vaccines do not induce broad cross-reactivity against drifted strains. Furthermore, fast vaccine production is especially important in a pandemic situation, and broader vaccine reactivity would diminish the need for frequent change in the vaccine formulations. OBJECTIVE In this study,...

The influenza virus transcribes and replicates its genome inside the nucleus of infected cells. Both activities are performed by the viral RNA-dependent RNA polymerase that is composed of the three subunits PA, PB1, and PB2, and recent studies have shown that it requires host cell factors to transcribe and replicate the viral genome. To identify these cellular partners, we generated a comprehen...

Background and Aims: The emergence of drug-resistant influenza viruses has become a serious threat for human and animal populations. Glycyrrhiza glabra (Gg) is a traditional medicine clinically used for the treatment of viral respiratory infection symptoms in most countries. We evaluated the effects of the herb on influenza virus replication in human lung cultured cells (A549) following the det...