New approaches to the treatment of influenza have been designed based on the highly conserved antigenicity of the M2 envelope protein among influenza A virus strains. The present study examined the anti-viral activities of an anti-M2 ectodomain (M2e) monoclonal antibody (clone rM2ss23), which binds to the M2 proteins of the influenza A virus strains A/ Aichi/2/68 (H3N2) (Aichi) and A/PJR/8/34 (...

OBJECTIVE to analyze the circulation of respiratory viruses in people living in the metropolitan area of Belo Horizonte, Brazil, and hospitalized in Belo Horizonte from 2011 to 2013. METHODS this is a descriptive study of 5,158 patients with Severe Acute Respiratory Syndrome; a comparison was made between the characteristics of confirmed cases and those of discarded cases or cases without swa...

Influenza A virus infects various animal species and transmits among different hosts, especially between humans and swine. Swine may serve as a mixing vessel to create new reassortants that could infect humans. Thus, monitoring and characterizing influenza viruses in swine are important in preventing interspecies transmission. We report the emergence and characterization of a novel H3N1 subtype...

Swine influenza (SI) was first observed at the time of the pandemic in humans in 1918, and since that time, subtypes H1N1 and H3N2 have been widely reported in pigs, frequently associated with respiratory disease. These include classical swine H1N1, avian-like H1N1 and humanand avianlike H3N2 viruses. Swine husbandry practices influence directly the evolution of SI viruses through reduced immun...

Influenza A virus (subtype H3N2) causes seasonal human influenza and is included as a component of influenza vaccines. The majority of vaccine viruses are isolated and propagated in eggs, which commonly results in amino acid substitutions in the haemagglutinin (HA) glycoprotein. These substitutions can affect virus receptor-binding and alter virus antigenicity, thereby, obfuscating the choice o...

In the rainy season of 1989, 72 strains of influenza viruses were isolated in Thailand by using MDCK cell cultures, which included 36 samples belonging to H1N1, 24 samples belonging to H3N2 subtype of type A and 12 samples of type B1). The identified viruses were inoculated into developing hen's eggs of 10 days' age, and 22 (32.6%) of them were adapted to the egg after one passage, which includ...

Human cases of infection due to a novel swine-origin variant of influenza A virus subtype H3N2 (H3N2v) have recently been identified in the United States. Pre-existing humoral and cellular immunity has been recognized as one of the key factors in limiting the infection burden of an emerging influenza virus strain, contributing to restrict its circulation and to mitigate clinical presentation. A...

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,...

Understanding the evolution of influenza A viruses in humans is important for surveillance and vaccine strain selection. We performed a phylogenetic analysis of 156 complete genomes of human H3N2 influenza A viruses collected between 1999 and 2004 from New York State, United States, and observed multiple co-circulating clades with different population frequencies. Strikingly, phylogenies inferr...