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BIRD FLU and YOU. Brookings Register , November 2005. INFLUENZA A. There are THREE known A subtypes of influenza viruses (H1N1, H1N2, and H3N2) currently circulating among humans. It is likely that some genetic parts of current human influenza A viruses came from birds originally.
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BIRD FLU and YOU Brookings Register, November 2005
INFLUENZA A • There are THREE known A subtypes of influenza viruses (H1N1, H1N2, and H3N2) currently circulating among humans. • It is likely that some genetic parts of current human influenza A viruses came from birds originally. • Influenza A viruses are constantly changing, and they can adapt over time to infect and spread among humans. Image from: http://www.msjanie.com/articles/sickness.jpg
AVIAN INFLUENZA(Bird Flu) • Infection caused by bird flu virus • Occurs naturally in wild birds • Wild birds carry virus in their intestines, but usually don’t get sick • Very contagious among birds • Can make domesticated birds (chickens, ducks, turkeys) very sick and kill them Image from: http://www.friedmanarchives.com/Nepal/images/Chicken%208x10%20300%20dpi.jpg
Why worry about Bird Flu if it is a bird disease? • Three strains of bird flu (H5N1, H9N2 and H7N7) have been transmitted to people • H5N1 is genetically similar to the H1N1 virus strain that caused the 1918 Flu pandemic. • Most cases have occurred in previously healthy children and young adults. • It has a high mortality rate (50% of the humans infected so far have died)
H5N1 http://fotservis.typepad.com/photos/egypt/chicken_smoke.html • H5N1 virus does not usually infect people, but more than 140 human cases have been reported by the World Health Organization since January 2004 • Most of these cases resulted from people having direct or close contact with infected poultry or contaminated surfaces
Why worry about H5N1? • So far, the spread of H5N1 virus from person to person has been rare and has not continued beyond one person. • Nonetheless, because all influenza viruses have the ability to change, scientists are concerned that H5N1 virus one day could be able to infect humans and spread easily from one person to another. • Because these viruses do not commonly infect humans, there is little or no immune protection against them in the human population.
WHY WORRY? • A few cases of human-to-human spread of H5N1 have occurred, but have not spread beyond this initial infection • If H5N1 virus were to gain the capacity to spread easily from person to person, a worldwide outbreak of disease could begin. • In the current outbreaks in Asia and Europe, more than half of those infected with the virus have died.
Where in the world is H5N1? Influenza A (H5N1), has caused infections in birds and HUMANS in Asia and Europe (Cambodia, Tibet, Mongolia, Indonesia, Malaysia, Thailand, Vietnam, Kazakhstan, Siberia, Ukraine, and recently Turkey. Image from: http://www.stanford.edu/group/virus/uda/
Flu pandemics • 1918 Spanish flu killed 50 million • 1957 Asian flu killed around 1million • 1968 Hong Kong flu killed 1million • 1976 Swine flu was a “dud” Image from: http://plainbookofmormon.com/images/graves.jpg
Influenza Pandemic of 1918 • Infected 1/5 of world’s population and killed somewhere between 20 and 40 million people • It has been cited as the most devastating epidemic in recorded world history. • More people died of influenza in a single year than in four-years of the Black Death Bubonic Plague from 1347 to 1351. • Known as "Spanish Flu" or "La Grippe" the influenza of 1918-1919 was a global disaster.
http://www.stanford.edu/group/virus/uda/fluresponse.html FLU PANDEMIC of 1918 • Infected 28% of all Americans • An estimated 675,000 Americans died (ten times as many as in the World War I) • An estimated 43,000 U.S. servicemen mobilized for WWI died of influenza (1/2 of casualties were from flu NOT the war itself)
http://www.sdhistory.org/arc/flunewspapers.htm EVEN IN SOUTH DAKOTA 28% of people who died in South Dakota in 1918 died from INFLUENZA
http://www.sdhistory.org/arc/flunewspapers.htm PRECAUTIONS
INFLUENZA A (FLU) COMMON SYMPTOMS • Fever • Cough • sore throat • and muscle aches OTHER POSSIBLE • other infections • pneumonia • severe respiratory diseases • severe and life-threatening complications Image from: http://www.jobpilot.co.uk/binary/images/channels/legal/sickness.jpg
PREVENTION This is NOT an airborne disease so there are ways that you can protect yourself, • Wash your hands • Use cough etiquette • Stay home if you're sick • Stay away from people who are sick http://www.askthebrain.com/pics/588/Cough.jpg
Will a Flu Shot now protect me from Bird Flu? • The viruses in flu vaccine change each year based on which strain is expected to be the problem • Current vaccine protects against 2 strains of A (H3N2 & H1N1) 1 strain of B NOT AGAINST H5N1 • It takes about 2 weeks after vaccination for flu antibodies to develop in your body Image from: http://www.omedon.co.uk/influenza/beans/influenza%20virus.jpg
Can we make a NEW VACCINE? • There currently is no commercially available vaccine to protect humans against H5N1 virus • Research studies to test a vaccine to protect humans against H5N1 virus began in April 2005, and a series of clinical trials is under way http://news.bbc.co.uk/2/hi/europe/3524824.stm
CAN OTHER MEDICINE HELP? • The H5N1 virus that has caused human illness and death in Asia is resistant to amantadine and rimantadine, two antiviral medications commonly used for influenza. • There currently is no commercially available vaccine to protect humans against H5N1 virus that is being seen in Asia and Europe. Image from: http://www.stanford.edu/group/virus/uda/fluscimed.html
Tamiflu Anti-viral medicine • Can be used for prevention OR once you have virus • One pill protects you for one day • Experts believe the first wave in a given area would last up to 100 days. • You would need to stockpile about 100 doses of Tamiflu and start taking them from the moment you hear the virus is circulating in your region. • Shortage right now! http://www.cbc.ca/news/background/avianflu/avian-faqs.html#q8
WHAT IS BEING DONE? • World Health Organization (WHO) is monitoring ALL REPORTED cases around world • EARLY detection and intervention of first human to human infection is VITAL to STOPPING the spread and preventing a world wide EPIDEMIC
WHAT IS BEING DONE? • Several countries are currently testing a vaccine against H5N1 • Production of anti-virals (Tamiflu) has been increased • Public education about prevention and early detection • Plans by Governments for action in case of epidemic