H1N1 Pandemic virus

H1N1 PANDEMIC VIRUS

1.  What H1N1 Influenza A Means?
    All human influenza viruses belong to the Orthomyxoviridae virus family. This family includes Influenzas A, B, and C, Isavirus and Thogotovirus. Human influenza pandemics are usually caused by Influenza A.The influenza A virus is divided into subtypes, such as H1N1. The letters H and N refer to hemagglutinin and neuraminidase. Hemagglutinin and neuraminidase are antigens, proteins that provoke an immune response in the human body. The human body responds to antigens by producing antibodies. Antigens are categorized according to the antibodies that respond to them. There are 16 known hemagglutinin subtypes for influenza A (H1 to H16) and 9 known neuraminidase subtypes (N1 to N9). Each of these subtypes is vulnerable to a similar type of antibody.
    The influenza A virion is
   • a globular particle (about 100 nm in diameter)
   • sheathed in a lipid bilayer (derived from the plasma membrane of its host)
   • Studded in the lipid bilayer are two integral membrane proteins
   o some 500 molecules of hemagglutinin ("H") and
   o some 100 molecules of neuraminidase ("N")
   • Within the lipid bilayer are
   o some 3000 molecules of matrix protein
   o 8 pieces of RNA
   Each of the 8 RNA molecules is associated with
   • many copies of a nucleoprotein
   • several molecules of the three subunits of its RNA polymerase
   • some "non-structural" protein molecules of uncertain function 
2. How does H1N1 flu virus spread?
    Spread of the H1N1 flu virus is thought to be happening in the same way that seasonal flu spreads. Flu viruses are spread mainly from person to person through coughing or sneezing.. creating aerosols containing the virus, and from infected birds through their droppings. Influenza can also be transmitted by saliva, nasal secretions, feces and blood. Infections occur Sometimes people may become infected by touching contaminated objects or surfaces with flu viruses on it and then touching their mouth or nose.Flu viruses can remain infectious for about one week at human body temperature, over 30 days at 0 °C (32 °F), and indefinitely at very low temperatures (such as lakes in northeast Siberia). They can be inactivated easily by disinfectants and detergents.
    Infected people may be able to infect others beginning 1 day before symptoms develop and up to 7 or more days after becoming sick. That means that you may be able to pass on the flu to someone else before you know you are sick, as well as while you are sick. Children, especially younger children, might potentially be contagious for longer periods. This means that individuals who think they may symptoms should wash hands, cover cough/sneeze and contact their doctor
3. Mechanism of H1N1 Infections
    Flu strains are named for the H and N proteins, hemagglutinin and neuraminidase, which stick out from the surface of the virus like spikes. These protein spikes allow influenza to infect and damage cells and are what the immune system recognizes. The hemagglutinin spike allows the virus to bind to and enter cells. After co-opting the cells molecular machinery to produce more viruses, the neuraminidase spike is used to escape the cell, destroying it in the process. The 1918 influenza is an H1N1 strain and research on the reconstituted virus shows that it was particularly infective and had the unusual property of being able to infect mice, which typical human influenza strains cannot.