270 likes | 685 Vues
The Study of Viruses. Virology. What is Virology?. It’s a branch of the sciences which focuses on the study of viruses and organism’s. Viruses can be classified according to: Structure How they relate to each other How they work Host cells they infect Viral diseases they cause
E N D
The Study of Viruses Virology
What is Virology? • It’s a branch of the sciences which focuses on the study of viruses and organism’s. • Viruses can be classified according to: • Structure • How they relate to each other • How they work • Host cells they infect • Viral diseases they cause • Viruses range in size from 30nm to about 450nm, most of the viruses cannot be seen with light microscopes.
History • 3700 BC • First record of virus is portrayed through hieroglyphs in Egypt • 1000 BC • Smallpox in China • Viriolation is developed • 710 AD • Smallpox comes to Americas • 3,500,000 Aztecs die in 2 years time span • 1796 • Edward Jenner injects a boy with the cowpox and creates the cure for smallpox
History (cont’d) • 1885 • Louis Pasteur creates Rabies vaccine • Names the injections VACCINES in honor of Edward Jenner who used the Latin word Virus which means poison • 1886 • Smallpox seen under a microscope • 1898 • Modern idea of viruses • Not accepted by many as a human cause of sickness • 1900 • Yellow Fever kills many Americans in the Spanish-American war • Yellow Fever heads for the U.S. • Walter Reed discovers Yellow Fever is spread by mosquitoes1908 • Proof that viruses can infect human and animals alike • 1915 • Virus can infect bacteria is discovered by Fredrick Twort
History(cont’d) • 1937 • Vaccine for Yellow Fever • 1940 • First picture of virus using a microscope • 1952 • Polio Vaccine • 1963 • Measles Vaccine • First HBV Vaccine • 1976 • Ebola Virus Breakout • 1983 • HIV discovered • 1985 • WHO starts the “ Expanded Program on Immunizations” • Outline for vaccines needed in childhood • 1999 • Largest virus genome is completed of the Paramecium bursaria Chlorella virus 1
Who Discovered Virology? • D. Ivanoski first observed a virus that was the causative agent of the tobacco mosaic disease • Modern Virology began in the early 1900’s • The visualization of viruses becomes transparent • The first crystallized virus
Bioterrorism and Agroterrorism • Bioterrorism • Use of bacteria and/or viruses to cause harm to a mass population • Anthrax, Ebola, Smallpox, Tularemia, Botulinum toxin, Bubonic plague, Lassa Fever • Agroterrorism • Use of bacteria and/or viruses to infect livestock and crops • Wheat Rust, Rice Blast, Disorder Virus, Haize Streak Virus, Tomato Yellow Leaf Curl Virus
What Does the Future Bring? • Mutate quickly so no way to make vaccine • Possibility of superflu • Larger population=less area • Farmers are sleeping with animals • Animal to human spread • Viruses are becoming drug resistant • More people are treated with antibiotics which gives way to the resistance • HIV vaccine trial • Researchers are using this success as a guideline for future vaccines for all viruses
Treatments • There are a few antibiotics that relieve some symptoms • Researchers still looking for a vaccine to mold to current and new forms
Organisms included in Virology • Ebola HPV Yellow Fever Influenza Hepatitis
Ebola • Viral Hemorrhagic Fever • Victims bleed out • 70-90% fatality rate • Unknown how humans contracted • Suspected animal or insect from Africa • Human to human spread • In contact with bodily fluids or infected needles • Symptoms • Fever • Headache • Joint and muscle aches • Sore throat • Weakness • Diarrhea • Vomiting • Stomach pain • After onset patient starts bleeding from eyes, nose, mouth, ears and pores.
HPV • Human Papilloma Viruses • Controversial • Too new • Shouldn’t effect at young age bracket • Too young means that another vaccine is needed • Not certain on side effects caused • Could lead to genital warts and cervical cancer • Men are carriers • Sexually active women are at risk • Side effects to the vaccine
Yellow Fever • Other names of yellow fever; Yellow Jack, black vomit, yellow death, or American Plague • An acute viral disease • It has been a source of several epidemics • Symptoms include fever, chills, bleeding into the skin, N & V, rapid heart beat, etc… • So far there are not any treatments, but vaccination is important
Yellow Fever Continued…… • Signs of yellow fever • blood • black vomit • yellowish skin color (jaundice) • headache • fever
Hepatitis • Transmission • Hepatitis A is transmitted through fecal matter on skin, in water and in food • Hepatitis B is transmitted through bodily fluids • Symptoms • Fever • Fatigue • Loss of appetite • N&V • Abdominal pain • Light-colored stools • Dark urine • Jaundice • Muscle or joint pain
Influenza • Also called ( Flu) it’s acute, highly contagious disease caused by a virus. • Responsible for the “Spanish” flu in 1918 killing 675,000 people in the U.S. and an estimated 20-50 million people worldwide. • Three Types: A, B, C • Named after where the illness started. • A: Asia, B: Brazil, C: Not named. • Type A: most common and most dangerous. It infects a wide variety of birds, animals, and people. Responsible for regular out breaks. • Type B: only infects humans, produces milder illness. Seen more in residential communities like nursing homes • Type C: only infects humans, very mild. Common but seldom causes disease symptoms.
Influenza Continuation • Transmitted easily from person to person via droplets and small particles produced when infected people cough or sneeze. • Spreads rapidly in seasonal epidemics. • Most recover within one to two weeks • Affects all age groups, the highest incidence occurs in school children. • Greatest severity is in young children, elderly people, immunosuppressed people, and those with chronic diseases.
Influenza Symptoms and Treatments • Weaknesses, fatigue, muscle aches, headaches, fever (101 to 102 degrees), sneezing, and maybe a runny nose. • Bed rest, drink extra fluid- at least one full glass of water or juice every hour. • Acetaminophen (Tylenol), or Ibuprofen can relieve head and muscle aches. • Aspirin should be void for children. • Two newer medications: Relenza and Tamiflu • Relenza: inhaled powder- patients with lung problems should not use. • Tamiflu: oral medication.
When to call a doctor • After three days of fever over 102 F • If cough brings up heavy mucus • Difficult in breathing • If you get better, then you get worse again • If flu-like symptoms occur 10 days to three weeks after a tick bite because of possibility of Lyme’s Disease.
Prevention of Influenza • Immunization (Reaction) inflammation at the injection site to a mild flu symptoms. Flu shot non-life virus • Approved new mist vaccine (FluMist) for patients between the age of 5 and 65. cannot be given to patients that are pregnant or weak immune systems because it includes a life virus. • Vaccinate Every Year around the month of September or as soon vaccine is available. • If resistance is down, avoid markets, shopping malls, theaters, or crowded places. • Avoid from becoming overly tired or rundown. • Keep your distance from people who cough or sneeze. • Clean Hygiene: Wash hands regularly
References • Virology. ( 2010). In Encyclopedia Britannica. Retrieved from Encyclopedia Britannica Online • Newsweek. Kate Dailey. May 4, 2009 August 2, 2010 www.newsweek.com/2009/05/03/the-next-pandemic.print.html • The Scientist. Victoria Stern. November 30, 2009 www.the-scientist.com/blog/print/56189/
References (cont’d) • Help Prevent Hepatitis A and Hepatitis B. Web. 18 Aug. 2010. http://www.helppreventhepatitis.com/index.html • "Ebola Hemorrhagic Fever | CDC Special Pathogens Branch." Centers for Disease Control and Prevention. 17 July 2009. Web. 18 Aug. 2010. http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/ebola/qa.htm • N2h, By. "Agroterrorism Agents and Their Methods of Dissemination (Part 4) « Agriculture Business Week." Agriculture Business Week. 17 Jan. 2009. Web. 18 Aug. 2010. http://www.agribusinessweek.com/agroterrorism-agents-and-their-methods-of-dissemination-part-4/
References (cont’d) • Then, By. "Bioterrorism." The Virtual Museum of Bacteria. 06 Mar. 2009. Web. 18 Aug. 2010. http://www.bacteriamuseum.org/cms/Special-features/bioterrorism.html