InfluenzaMichelle Lin

Classic Flu SymptomsInfection

Incubation (1-2 days)

Symptoms (1-2 weeks)

Image: http://www.answers.com/topic/influenza

Betts, Robert, Stanley Chapman, and Robert Penn. A Practical Approach to Infectious Diseases. 5. Philadelphia: Lippincott Williams and Wilkins, 2003. 278-287. Print.

Who is at Risk?

Van-Tam, Jonathon, and Chloe Sellwood. Introduction to Pandemic Influenza. Oxfordshire, UK: CABI, 2010. 3-12. Print.

Image: http://breastfriendscafe.co.uk/2011/01/getting-baby-diagnosed-with-reflux/Image: http://lightitupecig.com/aboutus.aspx

Image: http://www.asklubo.com/en/health/what-to-do-if-i-have-a-terrible-cold-while-being-pregnantImage: http://oursicksociety.blogspot.com/2011/05/caring-for-elderly.html

Modes of Flu Transmission

3 Basic Modes:• Direct• Airborne• Indirect

Van-Tam, Jonathon, and Chloe Sellwood. Introduction to Pandemic Influenza. Oxfordshire, UK: CABI, 2010. 3-12. Print.Image: http://www.medicinenet.com/influenza/article.htm

The Taxonomy of Influenza Virus• Orthomyxoviridae

family• Genera (Types) – A, B, C– Antigenic differences

Image: http://www.aht.org.uk/cms-display/science_eqflu.htmlNicholson, Karl., Robert Webster, et al. Textbook of Influenza. Oxford: Blackwell Science Ltd, 1998. 29-38. Print

Structure of Influenza Virus

• Spherical• Enveloped• Matrix protein• Membrane

proteins• Nucleocapsid• 8 -ssRNAs

Image: http://micro.magnet.fsu.edu/cells/viruses/influenzavirus.htmlNicholson, Karl., Robert Webster, et al. Textbook of Influenza. Oxford: Blackwell Science Ltd, 1998. 29-38. Print

The viral genome is composed of segmented negative-sense RNA

Influenza A virus RNA segments and the proteins they encode

RNA segment (no. of nucleotides)

Gene product (no. of amino acids)

Molecules per virion

1 (2341) Polymerase PB2 (759)

30–60

2 (2341) Polymerase PB1 (757)

30–60

3 (2233) Polymerase PA (716)

30–60

4 (1778) Haemagglutinin (566)

500

5 (1565) Nucleoprotein (498) 1000

6 (1413) Neuraminidase (454)

100

7 (1027) Matrix protein M1 (252)

3000

Matrix protein M2 (97)

20–60

8 (890) Non-structural proteins

•NS1 (230) –

•NS2 (121) 130–200

Nicholson, Karl., Robert Webster, et al. Textbook of Influenza. Oxford: Blackwell Science Ltd, 1998. 29-38. Print

Image: http://www.rapidreferenceinfluenza.com/chapter/B978-0-7234-3433-7.50009-8/aim/influenza-virus-structureImage: http://www.annualreviews.org/doi/full/10.1146/annurev.micro.62.081307.162746

RNA-dependent RNA Polymerase synthesizes RNA from RNA

Image: http://www.pnas.org/content/107/25/11153/F1.expansion.html

3’

3’3’

3’

5’

5’5’

5’

Kawaoka, Yoshihiro. Influenza Virology: Current Topics. Norfolk: Caister Academic Press, 2006. 1-24. Print.

Li, Mei-Ling, Bertha Ramirez, and Robert Krug. "RNA-dependent activation of primer RNA production by influenza virus polymerase: different regions of the same protein subunit constitute the two required RNA-binding sites." EMBO Journal. 17 (1988): 5844-5852. Web. 6 Mar. 2012. <http://www.nature.com/emboj/journal/v17/n19/full/7591278a.html>.

Hemagglutinin (HA) assists in viral entry

Image: http://home.cc.umanitoba.ca/~hultin/chem2220/Support/CoolStuff/Influenza/Neuraminidase.htm

"Molecule of the Month: Hemagglutinin." RCSB PDB Molecule of the Month. 2012: n. page. Web. 6 Mar. 2012. <http://www.rcsb.org/pdb education_discussion/molecule_of_the_month/download/Hemagglutinin.pdf>.

Nicholson, Karl., Robert Webster, et al. Textbook of Influenza. Oxford: Blackwell Science Ltd, 1998. 29-38. Print

Image: http://www.rapidreferenceinfluenza.com/chapter/B978-0-7234-3433-7.50009-8/aim/influenza-virus-structure

M2 is a membrane ion channel protein

Nicholson, Karl., Robert Webster, et al. Textbook of Influenza. Oxford: Blackwell Science Ltd, 1998. 29-38. Print

M2 Membrane Channel

Image: http://wenliang.myweb.uga.edu/mystudy/virology/ScienceOfVirology/Entry(penetration).html

Neuraminidase (NA) assists in viral exit

Nicholson, Karl., Robert Webster, et al. Textbook of Influenza. Oxford: Blackwell Science Ltd, 1998. 29-38. Print

Image: http://www.interactions.org/sgtw/2006/0510/avianflu_more.htmlImage: http://www.virology.ws/2009/05/04/influenza-virus-attachment-to-cells/

Life Cycle of Influenza Virus

Van-Tam, Jonathon, and Chloe Sellwood. Introduction to Pandemic Influenza. Oxfordshire, UK: CABI, 2010. 18-21. PrintImage: http://www.ch.ic.ac.uk/local/projects/sanderson/immunology.htm

Anti-Influenza Drugs Block a Step in the Replication Cycle

Image: http://www.nature.com/nbt/journal/v28/n3/fig_tab/nbt0310-239_F1.htmlVan-Tam, Jonathon, and Chloe Sellwood. Introduction to Pandemic Influenza. Oxfordshire, UK: CABI, 2010. 23-24. Print

Betts, Robert, Stanley Chapman, and Robert Penn. A Practical Approach to Infectious Diseases. 5. Philadelphia: Lippincott Williams and Wilkins, 2003. 278-287. Print.

Antigenic Drift and Shift Contribute to the Genetic Variability of Influenza virus

Van-Tam, Jonathon, and Chloe Sellwood. Introduction to Pandemic Influenza. Oxfordshire, UK: CABI, 2010. 23-24. PrintImage: http://quizlet.com/2514798/micro-ch22c-flash-cards/

Annual Vaccines are Used to Prevent Influenza

• Inactivated vs. Live-attenuated• New each season

Nicholson, Karl., Robert Webster, et al. Textbook of Influenza. Oxford: Blackwell Science Ltd, 1998. 3-16. Print.

"Vaccine Selection for the 2011-2012 and 2012-2013 Influenza Seasons." Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 23 Feb 2012. Web. 6 Mar 2012. <http://www.cdc.gov/flu/about/qa/vaccine-selection.htm>.

Image: http://www.flushots2010.net/Image: http://topnews.us/content/226598-preparedness-flumist-program-season