About our cover.
Subject: Swine influenza
Pub Date: 11/01/2009
Publication: Name: The American Biology Teacher Publisher: National Association of Biology Teachers Audience: Academic; Professional Format: Magazine/Journal Subject: Biological sciences; Education Copyright: COPYRIGHT 2009 National Association of Biology Teachers ISSN: 0002-7685
Issue: Date: Nov-Dec, 2009 Source Volume: 71 Source Issue: 9
Accession Number: 246348908
Full Text: [ILLUSTRATION OMITTED]

On the cover are electron micrograph images of the Influenza A Type H1N1 virus. The actual diameter of this virus is approximately 0.1 micrometer. This is a variant of the common influenza found to infect humans and is referred to by the media as swine flu because the virus can cross between swine and humans, in June 2009, the World Health Organization declared that flu due to this new strain of swine-origin H1N1 was responsible for the 2009 flu pandemic, marking the first global pandemic since the 1968 Hong Kong flu.

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 R flu infections in 2006. Other strains of H1N1 are endemic in pigs and in birds.

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 structures of these proteins differ from strain to strain, due to rapid genetic mutation in the viral genome. This issue of the ABT focuses on Health and Medicine. Image: [c] Axelkock | Dreamstime.com
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