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Poliovirus. By Brittany Simpson November 6, 2012. Polio was a prevalent disease world-wide in the mid -1900’s. http:// www.polioeradication.org / Dataandmonitoring / Poliothisweek / Poliocasesworldwide.aspx. In contrast, in 2011 polio is close to eradication.
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Poliovirus By Brittany Simpson November 6, 2012
Polio was a prevalent disease world-wide in the mid-1900’s http://www.polioeradication.org/Dataandmonitoring/Poliothisweek/Poliocasesworldwide.aspx
In contrast, in 2011 polio is close to eradication http://www.polioeradication.org/Dataandmonitoring/Poliothisweek/Poliocasesworldwide.aspx
Polio is even closer to eradication this year http://www.polioeradication.org/Dataandmonitoring/Poliothisweek/Poliocasesworldwide.aspx
Notice complete eradication from India! http://www.polioeradication.org/Dataandmonitoring/Poliothisweek/Poliocasesworldwide.aspx
In the last six months, polio has come even closer to being completely erradicated. http://www.polioeradication.org/Dataandmonitoring/Poliothisweek/Poliocasesworldwide.aspx
Polio is transmitted through the fecal-oral route, so it can be prevented through proper hygiene. http://www.politedissent.com/images/dec09/polio.jpg
Polio symptoms generally consist of mild flu-like symptoms http://spcsites.com/livewellwyobraska/wp-content/uploads/2010/12/10377.jpg
However, in 1 in 200 people it may cause severe paralysis and death http://students.cis.uab.edu/sajayi11/poliopatient.jpg http://2.bp.blogspot.com/_ChxfFH9ehDU/SxUHUXQxL6I/AAAaA/V9ZnXP1Hn1g/s1600/polio.jpg
Poliovirus is a picornavirus– one of the smallest in existence- and more specifically is an enterovirus http://www.vetmed.ucdavis.edu/viruses/02-01_450.jpg
The virus is surrounded by a capsid with an icosahedral lattice structure for stability. http://www.cgl.ucsf.edu/chimera/experimental/hkcage/em_1f8v_small.png
Poliovirus is a positive single stranded RNA virus– this means once inside the cell it’s RNA can immediately be translated into proteins http://www.npspindia.org/images/Polio-Virus.jpg
Its genome consists of 7500 base pairs and codes for roughly 10 proteins http://education.expasy.org/images/Picornaviridae_genome.jpg
It codes for three major groups of proteins: Structural proteins, RNA Polymerase, and proteins of unknown function. http://www.nature.com/nm/journal/v4/n12/images/nm1298_1357.gif
The virus enters the cell by either active pinocytosis or penetration into the plasma membrane. http://www.nature.com/nrmicro/journal/v3/n10/thumbs/nrmicro1284-f1.gif
Once inside the cell, the capsid is removed and proteins are processed that shut down transcription of infected cell. http://www.nature.com/nrmicro/journal/v3/n10/thumbs/nrmicro1284-f1.gif
The positive stranded RNA replicates and makes a negative strand to make further copies from. http://www.dbc.uci.edu/~faculty/wagner/cycle03.jpg
The positive stranded RNA replicates and makes a negative strand to make further copies from. These copies are incorporated into newly created virions in the cell. http://www.dbc.uci.edu/~faculty/wagner/cycle03.jpg
Once the virions have been produced, the cell undergoes lysis to release the infectious virions to infect other cells in the body http://images.fineartamerica.com/images-medium-large/cell-lysis-kathryn-elliget.jpg http://www.sciencephoto.com/image/254451/530wm/M1320959-Cancer_cell_apoptosis,_SEM-SPL.jpg
Poliovirus often infects nerve cells which can lead to paralysis and eventually death http://www.polioaustralia.org.au/wp-content/uploads/2010/09/Degeneration-of-Nerve-cells-Neurons-during-Acute-Polio2-200x1024.jpg
Jonas Salk began working in the early 1950’s to create a vaccine for the virus that would be effective against all three strains http://www.achievement.org/achievers/sal0/large/sal0-012.jpg
Poliovirus is especially difficult to deactivate but it can be done by using extremely high temperatures, alkaline pHs, and certain chemical compounds
Poliovirus is especially difficult to deactivate but it can be done by using extremely high temperatures, alkaline pHs, and certain chemical compounds Salk used Formalin, a derivative of formaldehyde to deactivate the virus while leaving its basic structure intact. http://3.bp.blogspot.com/-iTBrI0M9a2k/UCqLIeMxpWI/AAAQw/U2g0diO7wlA/s1600/formalin-solution.jpg
A primitive form of the vaccine was created and then tested on monkeys and a small number of human subjects– no adverse effects were seen. http://imagecache6.allposters.com/LRG//37/3788/BE4IF00Z.jpg
Salk and his team moved on to full scale clinical trials, testing the vaccine on nearly 2 million children. http://schoolworkhelper.net/wp-content/uploads/2011/08/Jonas-Salk-2.jpg http://amhistory.si.edu/polio/virusvaccine/images/imgclinical_04.jpg
Salk and his team moved on to full scale clinical trials, testing the vaccine on nearly 2 million children. Vaccine is Released to the public April 15, 1955 http://schoolworkhelper.net/wp-content/uploads/2011/08/Jonas-Salk-2.jpg http://amhistory.si.edu/polio/virusvaccine/images/imgclinical_04.jpg
When the vaccine is introduced to the body, your immune system will create antibodies in response to the deactivated virus. http://madcatmedia.com/eureka/files/crystalStructure_Antibody.gif
When the vaccine is introduced to the body, your immune system will create antibodies in response to the deactivated virus. Now if you were to be infected, you would experience a secondary immune response and not fall ill with the disease! http://madcatmedia.com/eureka/files/crystalStructure_Antibody.gif
The number of cases dropped dramatically after the introduction of the vaccine! http://barlow.gresham.k12.or.us/Science/Anderson/Polio_Critical_Thinking_files/image002.jpg
A second form of the vaccine is later introduced by Albert Sabin which utilizes a weakened strain of the virus to be taken orally http://www.poliosurvivorsnetwork.org.uk/archive/lincolnshire/library/gawne/images/pandcmfig1.gif
This is more similar to the vaccines being used in modern times in developing countries. http://www.poliosurvivorsnetwork.org.uk/archive/lincolnshire/library/gawne/images/pandcmfig1.gif
Polio has been eradicated from almost every country in the world; it only remains in Nigeria, Afghanistan, and Pakistan. http://globalprosperity.files.wordpress.com/2012/01/polio-immunization-360-1-1.jpg http://vactruth.com/wp-content/uploads/2012/05/oral-polio-vaccine.jpg
The GPEI hopes to have the disease completely eradicated within the next two to three years, and is working to make IPV affordable in endemic countries. http://www.bt.cdc.gov/situationawareness/polio/images/GPEI.jpg