Infecting Influenza Virus
By: Kat Conley
What is the Flu?
How it Spreads:
The flu spreads through both direct and indirect contact with infected people. Droplets produced while talking, coughing or sneezing can be carried up to 6 feet away to infect another person; and even touching infected surfaces, followed by touching ones face, especially eyes and mouth can lead to 'self' contamination.
Cover your mouth!
Particles can travel in air and infect people up to 6 feet away.
Wash Your Hands:
Often, thoroughly wash and rinse hands under warm water.
Avoid touching common surfaces during cold and flu season as virus germs can be on most common surfaces.
These surfaces include:
• Sore throat
• Runny/ stuffy nose
• Muscle/ body aches
· Pneumonia: Due to fluid build up (mucus) in lungs
· Sinus/ Ear infections
· Increased asthma attacks
· Worsening of chronic conditions: heart failure
As the flu is a viral infection and normal Anti-bacterial drugs have no effect on viruses, it is treated with Anti-viral drugs. These drugs are not sold over-the-counter and are strictly by prescription. Currently, the U.S. FDA has approved and recommends 3 anti-viral drugs which include: Tamiflu®, Relenza®, and Rapivab®. Typically, these drugs are most helpful after no more than 1-3 days of flu-like symptoms, and help to, lessen severity, shorten duration, and prevent further complications. While they still lessen severity after the initial 3 days, they are no longer guaranteed to shorten the illness. Therefore, for older people (50+) or those with weak immune systems, it is important to catch thee symptoms early to prevent andy further complications.
Why do Flu shots change yearly?
· Antiviral Resistance
· As the virus replicates, the genetic sequence may change leading to viral resistance to one or more of the antiviral drugs used to treat or prevent influenza.
· Flu viruses can change spontaneously or emerge during the course of treatment
· The vaccine protects against an influenza A (H1N1) virus, an influenza A (H3N2) virus, and one or two influenza B viruses (depending on the vaccine)
What are the sources of new viral strains?
· Antigenic shift- Changes in structures of the influenza A virus two primary surface proteins: neuraminidase (NA) and hemagglutinin (HA)
- Usually emerges from an animal population, such as N1H1
· Antigenic drift- Small, continuously changing changes in the DNA as the virus replicates
- Usually produce viruses that are pretty closely related to one another
· Type A can undergo both types of shifts, but B only changes through antigenic shift
Assessing the Severity of the Flu each year
This group of pandemic researchers from the CDC has developed method by which they assess the yearly risk of the flu outbreak each year. They initially breakdown the analysis into two subcategories
-Emergence: Risk of a novel- new viral strain
-Public Health Impact: Potential severity of human disease as well as burden on society (i.e. sick days), due to virus
After assessing the virus in the initial two categories, researchers then evaluate the 'novel' virus based on ten criteria. Each of the criteria is then weighted statistically based on the significance of each to the two initial scenarios. These ten criteria can be separated into three distinct groups:
-Properties of the Virus
-Attributes of the Population
-Ecology and Epidemiology of the Virus
After completion of the statistical analysis of one flu season, it is then compared against records of past seasons to then determine overall severity.
Sunday, Sep. 1st 1918 at 9pm to Thursday, May 1st 1919 at 11pm
Monday, Sep. 1st 1969 at 9-11pm
Hong Kong Flu
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Influenza Risk Assessment Tool (IRAT) | Pandemic Influenza (Flu) | CDC. (n.d.). Retrieved from http://www.cdc.gov/flu/pandemic-resources/tools/risk-assessment.htm
What You Should Know About Flu Antiviral Drugs| Seasonal Influenza (Flu) | CDC. (n.d.). Retrieved from http://www.cdc.gov/flu/antivirals/whatyoushould.htm
"Home | Flu.gov." Home | Flu.gov. N.p., n.d. Web. 20 Oct. 2015.
Influenza (flu) - Mayo Clinic. (n.d.). Retrieved from http://www.mayoclinic.org/diseases-conditions/flu/basics/definition/con-20035101