01716naa a2200169 a 450000100080000000500110000800800410001910000220006024500630008226000090014552012750015465000220142965000190145165000110147065300160148177300490149720127582015-04-06       2013    bl uuuu     u00u1 u    #d1 aZANELLA, J. R. C.  aInfluenza vírus infection in pigs.h[electronic resource]  c2013  aInfl uenza A virus is a zoonotic agent of great relevance to human and animal health. Swine is an important host to the dynamics and epidemiology of the infection due to its susceptibility to viruses of both the avian and mammalian virus lineages. Th e great genetic variability of infl uenza viruses is caused by two main genetic mechanisms: point mutations and gene reassortment. Th e latter, by letting the exchange of gene segments between two diff erent infl uenza viruses infecting the same cell, allows a rapid evolution of infl uenza viruses and the emergence of reassortant viruses against which there is no immunity in the host (human or animal). Infl uenza is endemic in pigs in many countries and the emergence of new viruses has been challenging its control and diagnostics. Although infections with infl uenza A virus (IAV) are endemic in most of the pork producing countries throughout the world, in Brazil this pathogen has not received much attention. Since the emergence of the 2009 pandemic H1N1 infl uenza virus in pigs (H1N1pdm09), many outbreaks of respiratory disease were observed in Brazilian swine populations. Currently, in Brazil, H1N1, H3N2 and 2009 pandemic H1N1 (A(H1N1)pdm09) infl uenza A viruses (IAVs) circulate in domestic swine herds.  aInfluenza A virus  aSwine diseases  aSuíno  aInfluenza A  tVirus Reviews & Researchgv.18, n. 1-2, 2013