Search

Blog Archive

Some blind may say that the name H1N1 has originated from Mexico related to Swine flu. But influenza A virus subtype H1N1, also known as A(H1N1), is a subtype of influenza virus A and the most common cause of influenza (flu) in humans.
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 differs 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.
Some strains of H1N1 are endemic in humans, including the strain(s) responsible for the 1918 flu pandemic which killed 50–100 million people worldwide. Less virulent H1N1 strains still exist in the wild today, worldwide, causing a small fraction of all influenza-like illness and a large fraction of all seasonal influenza. H1N1 strains caused roughly half of all flu infections in 2006. Other strains of H1N1 are endemic in pigs and in birds.
Minor outbreaks of swine influenza occurred in humans in 1976 and 1988, and in pigs in 1998 and 2007. In the 2009 swine flu outbreak, the virus isolated from patients in the United States was found to be made up of genetic elements from four different flu viruses – North American Mexican influenza, North American avian influenza, human influenza, and swine influenza virus typically found in Asia and Europe – "an unusually mongrelised mix of genetic sequences."
This new strain appears to be a result of reassortment of human influenza and swine influenza viruses, in all four different strains of subtype H1N1.
However, as the virus has not yet been isolated in animals to date and also for historical naming reasons, the World Organisation for Animal Health (OIE) suggests it be called "North-American influenza". On April 30, 2009 the World Health Organization began referring to the outbreak as "Influenza A" instead of "swine flu"., and later began referring to it as "Influenza A(H1N1)". http://en.wikipedia.org/wiki/Influenza_A...

3 comments:

Chemist said...

The nomenclature 'H1N1' is best described as scientific jargon, unlike the media's usage of the appellation 'swine flu'... "Transmission of swine influenza virus from pigs to humans is not common and does not always cause human influenza, often only resulting in the production of antibodies in the blood."
"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 differs 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."

Penguin said...

Some strains of H1N1 are endemic in humans, including the strain(s) responsible for the 1918 flu pandemic which killed 50–100 million people worldwide. Less virulent H1N1 strains still exist in the wild today, worldwide, causing a small fraction of all influenza-like illness and a large fraction of all seasonal influenza. H1N1 strains caused roughly half of all flu infections in 2006. Other strains of H1N1 are endemic in pigs and in birds.

Shahana said...

H1N1: the H means hemagglutanin and the N is neurominadase, the 1 is the way these structure looks. Hemagglutanin and neurominadase are antigens. Hemagglutanin binds RBCs and receptors on the respiratory mucosa. Neurominadase hydrolyzes (deslimes) mucus coating of the respiratory tract and unglues viral bundles so that the particles can infect cells.

Post a Comment