In virology, influenza A virus subtype H1N1 (A/H1N1) is the subtype of Influenza A virus that was the most common cause of human influenza (flu) in 2009, and is associated with the 1918 flu pandemic.It is an orthomyxovirus that contains the glycoproteins haemagglutinin and neuraminidase.For this reason, they are described as H1N1, H1N2 etc. Human influenza viruses belong to the Orthomyxoviridae family, which consists of the genera influenza A, B, and C virus, thogotovirus (carried by ticks, and infecting humans), and isavirus (infecting fish), as well as of a few other, newly described arboviruses. people working in pig farms, etc. Author information: (1)Department of Respiratory Medicine, Capital Medical University, NO. The emergence of a new and very different influenza A virus with the ability infect people and have sustained human to human transmission, can cause an influenza pandemic. Influenza A virus causes influenza in birds and some mammals, and is the only species of the genus Alphainfluenzavirus of the virus family Orthomyxoviridae. Some isolates of influenza A virus cause severe disease both in domestic poultry and, rarely, in humans. 10 You-an -men-wai Xi-tou-tiao, Fengtai District, Beijing 10069, China. Zoonotic or variant influenza Humans can also be infected with influenza viruses that are routinely circulating in animals, such as avian influenza virus subtypes A(H5N1) and A(H9N2) and swine influenza virus subtypes A(H1N1) and (H3N2). Here, learn about the differences between influenza A and B, including their symptoms and treatments.

Influenza A and B are the most common types of flu in humans. Strains of all subtypes of influenza A virus have been isolated from wild birds, although disease is uncommon. After entering someone's body—usually via the eyes, nose or mouth—the influenza virus begins hijacking human cells in the nose and throat to make copies of itself. Pandemic and Avian Influenza A Viruses in Humans: Epidemiology, Virology, Clinical Characteristics, and Treatment Strategy.

Central to these planning efforts in the health-care sector are strategies to minimise the transmission of influenza to health-care workers and patients. Influenza Virus . Classification. Influenza A viruses infect humans and many different animals. Influenza viruses A, B and C are the 3 genera of influenza viruses that can cause human flu. Influenza B viruses circulates among humans and cause seasonal epidemics. Influenza virus .

Researchers finally isolated the virus that causes flu from pigs in 1931, and from humans in 1933. These findings usually occurred in people with direct and indirect exposure to pigs i.e. Since 1958, a total of 17 cases of swine influenza in humans have been reported in Europe. Background Infection of poultry with influenza A subtype H7 viruses occurs worldwide, but the introduction of this subtype to humans in Asia has not been observed previously.

Li H(1), Cao B(2). Planning for the next influenza pandemic is occurring at many levels throughout the world, spurred on by the recent spread of H5N1 avian influenza in Asia, Europe, and Africa. Only influenza A and B viruses cause epidemics in human beings. Human infections with swine influenza have been sporadically detected (or at least published in the literature) since the late 1950s. Other species including horses and dogs also have their own varieties of influenza viruses. To clarify the threat posed by emergence of highly pathogenic influenza A(H7N9) virus infection among humans, we characterized the viral polymerase complex.