Influenza epidemics have been documented throughout history, with the first reliable report from the 12th century. The most memorable of modern major flu pandemics occurred in 1918,
spreading rapidly worldwide and eventually killing more than 20 million people. The pandemic was nicknamed the "Spanish flu," although it did not originate in Spain,
but in a military camp in Kansas. In 1918, a soldier experienced the typical symptoms of a cough, running nose, sore throat, and headache and mistook them for a cold.
Unbeknownst to all, it was actually a new strain of influenza. The disease spread quickly, as troop ships transported the disease to many parts of the world, including Germany, France,
and England. Eight million people throughout Spain became ill with a similar strain of influenza; hence, the name. The disease continued to spread across Africa, South America,
and Canada. Within a few months more people had died of Spanish flu than of the Black Death in the Middle Ages.
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The Influenza Virus
Causes of Influenza
Like the common cold, the flu is transmitted by viruses—specifically, influenza viruses—that attack about 10% of people during a normal winter. Because influenza viruses are much
more aggressive and destructive than cold viruses, they demand a more forceful reaction from the immune system, which can weaken the body.
There are three types of the flu virus: A, B, and C. Flu viruses mutate rapidly, which means the immune system can no longer recognize the pathogens. Therefore, it is difficult for researchers
to develop effective vaccines that provide lifelong immunity.
Protection Against Influenza
The flu can be life threatening, especially to the elderly. Children or those taking medication for a chronic condition are also vulnerable due to potentially weakened immune systems.
The single best way to protect against the flu is to get vaccinated each year.
1 Potter, CW, A history of influenza, Journal of Applied Microbiology, 2001; 91: 572-579.
