Department of ealth and man services centers for disease control and prevention. Strains of all subtypes of influenza a virus have been isolated from wild birds, although disease is uncommon. Chapitre 7 grippe infection par le virus influenza. Terapia fisica psicoterapia educacion y control del. Influenza is caused by viruses in the family orthomyxoviridae. Department of health and human services centers for disease control and.
Influenza porcina influenza h1n1 sintomas y causas mayo. Influenza diagnosis clinical and epidemiological characteristics increase of febrile respiratory illness lab isolation of influenza virus from clinical specimen e. Influenza a is the most dangerous for humans, influenza c is the least dangerous. We are primarily involved in teaching, research and service. Influenza a virus causes influenza in birds and some mammals, and is the only species of the genus alphainfluenzavirus of the virus family orthomyxoviridae. Sequencing has confirmed that these viruses share a common genetic ancestry. The influenza a, b, and c viruses, representing three of the five genera of the family orthomyxoviridae, are characterized by segmented, negativestrand rna genomes. Pathology, microbiology and immunology school of medicine.
Some isolates of influenza a virus cause severe disease both in domestic poultry and, rarely, in humans. The biology of influenza viruses pubmed central pmc. Wo2011031125a1 proteinas recombinantes expresables en. Learn more about the classification of influenza viruses, influenza outbreaks, and influenza symptoms and treatment. Birds, pigs, horses, ferrets, dogs, and cats can all be infected with various strains of the influenza virus. Influenza in humans is often referred to as the seasonal flu. There are two different kinds of spikes, each made of a different protein one is the hemagglutinin ha protein and the other is the neuraminidase na protein the ha protein allows the virus to stick to a cell, so that it can enter into a host cell and start. H3n2 ne sapplique pas a dautres soustype h1n1 ou b, et les reinfections peuvent survenir. Influenza a virus est virus biologicum acido ribonucleico arn et simul species unica alphainfluenzavirorum et genus orthomyxoviridarum, quod homines, porcos, aves, equos, chiroptera afficiat et symptomata influentiae excitet introrsus virus quaedam gena portat, circa quae amictus brevi ante quasi praeda ex cellula tabernaria demptus virum vestit. Influenza virus has a rounded shape although it can be elongated or irregularly shaped and has a layer of spikes on the outside.
Algunos son contagiados por contacto directo entre personas y otros pueden ser contagiados por insectos. Influenza, acute viral infection of the upper or lower respiratory tract, marked by fever, chills, and a generalized feeling of malaise. How any one virus acquires its identification letter depends on differences in the matrix protein, nucleoprotein and response of antibodies to a particular strain. Department of health and human services centers for disease control and prevention. Influenza virus isolation in tissue cell culture from respiratory specimens. Influenza in birds is often referred to as avian influenza, in pigs as swine influenza, in horses as equine influenza and so on.
This work is licensed under a creative commons attribution. Historia natural influenza ah1n1 by karla martinez castro on. Laboratory testing for influenza virus infection may be done on pre or postmortem clinical specimens, and include identification of influenza a or b virus infections by a positive result by at least one of the following. Our research is wellfunded by grant support from federal sources such as the national institutes of health and from private foundations.