Influenza A Virus Subtype H1n1

Influenza A virus subtype H1N1 From Wikipedia, the free encyclopedia Jump to: navigation, search For the 1918 pandemic of Influenza A(H1N1), see 1918 flu pandemic. For the current pandemic of Influenza A(H1N1), see 2009 flu pandemic. Influenza

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Influenza Virus Avian influenza Swine influenza Flu season Research Vaccine Treatment A/H5N1 subtype A/H1N1 subtype

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Pandemic

Influenza A virus subtype H1N1, also known as A(H1N1), is a subtype of influenzavirus A and the most common cause of influenza (flu) in humans. Some strains of H1N1 are endemic in humans and cause a small fraction of all influenza-like illness and a large fraction of all seasonal influenza. H1N1 strains caused roughly half of all human flu infections in 2006.[1] Other strains of H1N1 are endemic in pigs (swine influenza) and in birds (avian influenza). In June 2009, WHO declared that flu due to a new strain of swine-origin H1N1 was responsible for the 2009 flu pandemic. This strain is commonly called "swine flu".

Nomenclature

The various types of influenza viruses in humans. Solid squares show the appearance of a new strain, causing recurring influenza pandemics. Broken lines indicate uncertain strain identifications.[2] Influenza A virus strains are categorized according to two proteins found on the surface of the virus: hemagglutinin (H) and neuraminidase (N). All influenza A viruses contain hemagglutinin and neuraminidase, but the structure of these proteins differ from strain to strain due to rapid genetic mutation in the viral genome. Influenza A virus strains are assigned an H number and an N number based on which forms of these two proteins the strain contains. There are 16 H and 9 N subtypes known in birds, but only H 1, 2 and 3, and N 1 and 2 are commonly found in humans.[3]

IN

HEA LTH 1. beaker - a liquid-measuring container 2. burette - measures volume of solution 3. clay triangle - a wire frame with porcelain used to support a crucible

4. wire gauze - used to spread heat of a burner flame 5. test tube - used as holder of small amount of solution 6. forceps - holds or pick up small objects 7. graduated cylinder - measures approximate volume of liquids 8. graduated pipette - measures solution volumes 9. condenser - used in distillation 10. crucible - used to heat a small amount of a solid substance at a very high temperature 11. funnel - used to transfer solids and liquids without spilling 12. thermometer - measures temperature 13. balance - measures mass of material 14. pH meter - measures acidity of solutions 15. centrifuge - separates materials of varying density