1. The word “influenza” comes from the Italian influentia because people used to believe that the influence of the planets, stars, and moon caused the flu—for only such universal influence could explain such sudden and widespread sickness.^b
2. The English adopted the word “influenza” in the mid-eighteenth century, while the French called it la grippe from gripper, meaning “to grasp or hook.” There is also a similar-sounding phrase in Arabic, anf-al-anza, which means “nose of the goat,” used because goats were thought to be carriers of the disease.^b
3. Annual flu viruses (not including flu pandemics) infect up to 20% of Americans, put 200,000 in the hospital with flu-related complications, and kill about 36,000 people.^c
4. The cost of treating annual flu epidemics, including lost wages and productivity of workers, is billions of dollars each year in just the United States alone.^d
5. The World Health Organization (WHO) estimates that between three and five million people worldwide get a serious case of the regular flu each year; tens of millions get milder cases. Between 250,000 and 500,000 people globally die of the flu every year.^h
6. There have been four major global flu pandemics since 1900. The most recent pandemic is the current swine flu (officially named “Novel H1N1 Influenza A”). The last global pandemic was the Hong Kong flu (1968-1969) which killed approximately one million people. The Asian flu pandemic (1957-1958) originated in China and is estimated to have killed between one and four million people. The Spanish flu pandemic (1918-1919) killed between 50-100 million people worldwide.^j
7. Scientists believe that flu pandemics occur two or three times each century.^f

The Spanish flu was the single deadliest plaque of the twentieth century

8. The single deadliest flu pandemic in history was the Spanish flu pandemic during 1918-1919. Occurring in the three waves of increasing lethality, the Spanish flu killed more people in 24 weeks than AIDS did in 24 years. It also killed more people in one year than smallpox or the Black Plague did in 50 years.^e
9. The Spanish flu killed more Americans in one year than the combined total who died in battle during WWI, WWII, the Korean War, and the Vietnam War.^e
10. At the University of Michigan at Ann Arbor, any student caught without a mask during the Spanish flu was automatically suspended, and a town in Arizona passed a law forbidding people to shake hands.^e
11. The Spanish flu was sometimes called “the purple death” because the worst symptom, signally certain death, was known as “heliotrope cyanosis,” when the lungs were starved of oxygen and the patient would turn purple, black, or blue.^e
12. “Cures” for the Spanish flu included drinking whiskey, smoking cigars, eating milk toast, gargling with salt water, getting fresh air, and partaking of interesting concoctions like “Grippura.” Some doctors doused their patients with icy water while others “bled” their patients. Yet other doctors tried surgery by slicing open a patient’s chest, spreading his ribs, and extracting pus and blood from the pleural cavity (the cavity surrounding the lungs), which was almost always fatal in flu victims.^e
13. Native Americans died at a rate four times the national average from the Spanish flu.^e
14. Novel Influenza A H1N1 (swine flu) first caused widespread illness in Mexico and the United States in March and April 2009, though Mexico may have been in the midst of the epidemic some months before. The first case in the United States was confirmed by the CDC on April 15, 2009.^f
15. As of 2009, scientists have identified two strains of the swine influenza: the influenza C virus and subtypes of the influenza A virus, specifically H1N1, H1N2, H3N1, and H2N3. Currently, a new strain of the H1N1 subtype, known as “Novel H1N1 Influenza A” has reached pandemic proportions.^f
16. The H1N1 form of swine flu is one of the descendants of the complex strain that caused the 1918 flu pandemic. It is called the “swine flu” because the overall structure of the virus is of the type that affects pigs, though other components besides swine are in the virus structrue.^a The “H” and “N” in H1N1 stand for Hemagglutinin and Neuraminidase, which are key molecular components of the virus.^b

Concern over pork sales have led U.S. officials to rename the “swine flu“ the “2009 H1N1 flu“

17. The Center for Disease Control (CDC) has begun to call the swine flu the “Novel Influenza A (H1N1)”.^g The World Health Organization (WHO) has renamed the swine flu the “Influenza A (H1N1).”^f The name changes were implemented in an effort to protect the pork industry, though the changes have caused some political debate.
18. Historically, the swine flu hasn’t spread person to people and rarely infects people who had direct contact with pigs. The current strain of swine flu is different and more dangerous because the swine flu virus has mutated so it can spread easily and possible further mutations are hard to predict. Additionally, because it is a new virus, few people have immunity.^f
19. The symptoms of the swine flu include fever, cough, sore throat, runny nose, body aches, headache, chills, nausea, and fatigue. It may also include diarrhea and vomiting. Diagnosing the swine flu just from symptoms is difficult as these are also symptoms of other illnesses.^a
20. A negative swine flu test doesn’t mean you don’t have the H1N1 virus.^a
21. The new strain of swine flu spreads like the regular flu: breathing the tiny droplets from a cough or sneeze, or touching an object an infected person just touched and then touching your own face. Infected people can spread the flu a day before they know they are sick and can be infectious for up to seven days after getting sick.^f
22. When fitted properly, respirators such as N95 (or higher) may slow the spread of viruses in combination with other precautions such as hand washing and avoiding crowds. Respirators are more difficult to breathe through than face masks and may be unsuitable for children or those with facial hair. A respirator should be worn only once and then discarded. The CDC does not know if respirators are effective barriers from the novel H1N1.^g
23. In contrast to respirators, face masks (surgical, dental, isolation, or laser masks) do not form a tight seal around the face and block only large droplets, not small viruses, from coming into contact with the wearer’s mouth and nose.^g
24. There is some immunity to Novel H1N1 in people born before 1957. Their immunity may be a result of a previous exposure to a related virus or to a seasonal flu vaccine.^f

Because they are more susceptible to the H1N1 flu, pregnant women will be among the first to receive the vaccine

25. The Department of Homeland Security has released 25% of its stores of the flu medications Roche Holding AG’s Tamiflu (oseltamivir phosphate) and GlaxoSmithKline Plc’s Relenza (Zanamivir) and it has asked people not to stockpile them. There is currently no vaccine for the swine flu, but it is extremely optimistic that there will be one available for winter 2009.^e
26. Swine flu vaccines may involve an astounding 600 million doses, far eclipsing the 115 million doses of season flu vaccines. Additionally, because the swine flu and seasonal flu may circulate together, analyzing possible side effects of the H1N1 vaccine may be difficult.ⁱ
27. Flu viruses can live up to 48 hours on hard, nonporous surfaces such as stainless steel and up to 12 hours on cloth and tissues. They can remain infectious for about one week at human body temperature, over 30 days at freezing temperatures, and indefinitely at temperatures below freezing.^c
28. The United States government suggests citizens should have a two-week supply of water and food, a supply of necessary prescription drugs, and a supply of nonprescription drugs in case of flu quarantines or other emergencies.^g
29. The current H1N1 virus contains genetic elements from North American swine flu, North American avian flu (bird flu), and human and swine flus typically found in Asia and Europe. The CDC says it is “an unusually mongrelized mix of genetic sequences.”^g
30. Like the Spanish flu pandemics of 1918-1919, the 2009 Novel H1N1 flu appears to be more serious in younger, healthy people, perhaps due to what scientists call a “cytokine storm,” or when the immune system overreacts and damages the body.^f
31. In 1976, an Army recruit at Fort Dix, New Jersey, died of a variant of the swine flu, known as A/New Jersey/1976 (H1N1). When another strain began circulating in the U.S. (A/Victoria/75 H3N2) simultaneously, public health officials persuaded President Gerald Ford to vaccinate 40 million Americans. The vaccinations were called off when people became concerned the vaccine was worse than the virus, especially when over 500 Americans contracted Guillain-Barre syndrome. Intensive litigation followed.^k
32. In 1988, a swine flu virus killed pregnant 32-year-old Barbara Ann Wieners after she visited a hog barn at a country fair in Wisconsin. Doctors were able to induce labor and deliver a healthy daughter before she died. Though those working with pigs and those she came into contact with tested positive for swine flu, there was no community outbreak.^k
33. Pigs are unusual because they can become infected with influenza strains that can infect three different species: pigs, birds, and humans. This makes pigs a perfect breeding ground for new and dangerous strains of influenza.^k
34. Virologists are not certain about the origins of the viruses, though they have three theories: (1) they started as living cells and devolved into simpler organisms, (2) they originated as primitive particles capable of replicating themselves, and (3) they were once parts of cells that broke away to evolve separately.^c
35. Viruses are between 20 and 100 times smaller than bacteria and can be seen only through a microscope.^c
36. Viruses (from the Latin virus meaning “poison, slimy liquid”) are much simpler than bacteria. Viruses are just inert bundles of genetic material encased in a shell called a capsid or a fatty membrane called an envelope. The flu, for example, is caused by an RNA virus of the family Orthomyxoviridae (from the Greek orthos meaing “straight” and myxa meaning “mucous”).^d

Researchers are concerned that the quickly mutating H1N1 flu virus will change into a more dangerous and virulent form

37. Viruses mutate more in one day than humans did in several million years. They mutate so quickly due to their rapid rate of reproduction, their inability to fix their mutations, and their ability to exchange genes with one another.^d
38. In contrast to the swine flu (H1N1) which reached a Phase 6 alert on June 11, 2009, the avian or bird flu (H5N1) remained at a Phase 3 alert. There have been 262 reported deaths out of 433 cases of the avian flu since it emerged six years ago. The worst affected country has been Indonesia, with 115 dead out of 141 cases. The avian flu mortality rate was 61%.^k
39. SARS (severe acute respiratory syndrome) killed 774 people out of 8,000 people who have been infected in 20 countries in Asia, Europe, and the Americas. The mortality rate of SARS was 9.6%.^k
40. As of June 26, 2009, there are 59,814 cases of the H1N1 flu virus with 263 deaths. The mortality rate of of the swine flu is .44% so far.^k
41. While the swine flu has been relatively mild, the last three influenza pandemics of the century started with a similar mild wave, only to be followed by much more severe and serious waves of cases.^j
42. Air travel has significantly increased the speed with which diseases can spread. Most of the world’s great cities are now within a few hours of each other. As SARS showed, a virus that is in Hong Kong one day can be carried to any point in Southeast Asia within three or four hours, to Europe in 12 hours, and to North America in 18 hours. Nearly 1.5 billion passengers travel by air every year.^f
43. Today’s medical historians have traced the likely beginning of the Spanish flu not to Spain, but to Haskell County, Kansas, where people lived close to their pigs and poultry. When three Haskell County boys were shipped off to Fort Riley, Kansas in late 1917, they carried the virus with them, which spread from U.S. military bases to cities across the country. The virus then spread throughout Europe, brought over with the U.S. troops of WWI, and it returned to the United States in a much deadlier form. Astonished at the rapid and high mortality rate, Americans feared the Germans had put “flu bacteria” in Bayer aspirin or had sneaked the flu through Boston harbor.^e
44. Some historians blame President Woodrow Wilson’s (1856-1924) lingering case of the Spanish flu as the reason he unexpectedly caved into stringent French demands for the harsh peace terms that decimated Germany which, in turn, led to the rise of Adolf Hitler and WWII (1939-1945).^e
45. Even with today’s powerful antibiotics, bacterial pneumonia is the most common complication of the flu, and most flu-related deaths are due to it.^c
46. In 1933, British researchers Wilson Smith, Christopher Andrews, and Patrick P. Laidlaw were the first to identify the human flu virus by experimenting with ferrets.^b
47. Thomas Francis and Jonas Salk (who later developed the polio vaccine) developed the first flu vaccine in 1944. These early vaccines often contained impurities that produced fever, headaches, and other side effects. The flu vaccine in its various forms has been used for over 60 years and over 90 million Americans get a flu shot each year.^b

Those who have a severe allergy to eggs may have a reaction when given a flu vaccine

48. The source of flu vaccines are chickens and, consequently, vaccines can be dangerous to people who are allergic to eggs. Those people should never receive the injectable or nasal spray vaccine without doctor’s approval.^d
49. Reyes syndrome is a rare and potentially fatal disorder linked to taking aspirin during viral illnesses such as the flu. Symptoms include persistent vomiting, fever, and confusion. Liver and brain damage occur within a few days. Many doctors advise against giving aspirin to children and young people for treating the symptoms of influenza-like symptoms. Dozens of cold and flu remedies contain aspirin.^d
50. The first possible influenza epidemic may have occurred in Europe as early as 1173.^b
51. Some historians believe that the Native Americans on the island of Hispaniola were hit by a swine flu epidemic in 1493 carried by pigs aboard Columbus’ ships.^b
52. In 1878, a “fowl pest” disease causing high mortality rates in poultry was first identified in Italy.^b
53. The first well documented human pandemic occurred in 1889-90 and was called the Russian flu (H2N2) and killed approximately one million people.^b
54. In the mid 1930s, scientists developed a new electron microscope that enabled them to see and photograph influenza virus (the flu was once thought to be caused by bacteria). In the following years, influenza types A, B, and C were isolated and identified. Type A influenza causes most human sickness and the major pandemics. Exposure to one strain appears to provide no protection or immunity to another.^f
55. For reasons that are still puzzling, there was far less panic during many other great plagues of the past than there is about today's flus, even though they killed so many. Scholars speculate that the Spanish flu may have been overshadowed by WWI.^b

-- Posted July 19, 2009

References

^a DeNoon, Daniel. “Swine Flu Symptoms.” Webmd.com. June 28, 2009. Accessed: June 28, 2009.

^b Dobson, Mary. 2007. Disease: The Extraordinary Stories behind History’s Deadliest Killers. London, UK: Quercus.

^c Friedlander, Mark P., Jr. 2009. Outbreak: Disease Detectives at Work. Minneapolis, MN: Twenty-First Century Books.

^d Goldsmith, Connie. 2007. Influenza: The Next Pandemic? Minneapolis, MN: Twenty-First Century Books.

^e Iezzoni, Lynette. 1999. Influenza 1918: The Worst Epidemic in American History. New York, NY: TV Books, L.L.C.

^f “Influenza A (H1N1).” WHO.int. June 2009. Accessed: June 28, 2009.

^g “Interim Recommendations for Facemask and Respirator Use to Reduce Novel Influenza A (H1N1) Virus Transmission.” CDC.gov. May 27, 2009. Accessed: June 27, 2009.

^h Silverstein Alvin and Virginia and Laura Silverstein Nunn. 2006. The Flu and Pneumonia Update. Berkeley Heights, NJ: Enslow Publishers, Inc.

ⁱ Stobbe, Mike. “Swine Flu Shot Campaign Could Involve 600M Doses.” KSL.com. June 16, 2009. Accessed: June 28, 2009.

^j Walsh, Byran. “A Brief History of: Flu Pandemics.” Time.com. April 30, 2009. Accessed: June 28, 2009.