Influenza

Description of virus that causes the disease.

• Offshoot of Orthomyxoviruse subfamily
• 80-120nm in size
• Spherical shaped
• Segmented RNA strands
• Envelope protecting the nucleic acid with glycoprotein spikes attached

Influenza particle

Viral Specificity:

• Enters in the respiratory system of host to penetrate mucin layer in the respiratory tract
• Infects respiratory epithelial cells in the respiratory tract

Symptoms and progression of the disease:

• The disease can have an incubation period of 1-4 days
• Typical flu symptoms include headaches, chills, and coughing
• Other symptoms that may occur are nausea, vomiting and diarrhea
• Influenza symptoms may not appear in people who have been exposed to similar viruses or had a vaccine
• Usually the flu would only last 1-2 weeks, but can last 1 month in severe cases

Common Methods of Transmission:

• Most commonly transmitted by aerosols from sneezing and coughing
• Can be breathed in if airborne virus
• Also can be transmitted by touch in certain case

Transmission

Treatment and Prevention:

• When infected with disease most people are treated with the influenza vaccine
• Basic prevention can be just washing hands to avoiding infected people

Miscellaneous:

Historical Background of Influenza

History of influenza

• H1N1 virus has a higher fatality rate
• Three rapid pandemic waves of the H1N1 appeared in 1918-1919
• The 2009 swine flu is a mixture of swine, avian and human influenza viruses
• Later variations of each influenza type is less fatal as the original virus type.

Resources accessed:

Author: Patricia L Hibberd
http://www.influenzareport.com/ir/virol.htm

http://www.microbiologybytes.com/virology/Orthomyxoviruses.html#ortho

http://www.vaccineinformation.org/flu/qandadis.asp

http://www.uptodate.com/patients/content/topic.do?topicKey=~BH4EgxcnnYT6JYj

http://www.cdc.gov/ncidod/eid/vol12no01/05-0979.htm

http://www.historyofinfluenza.com/swine.aspx

http://www.ghi.com/topic.aspx?page=268