Tuesday, April 28, 2009

Wards Ap Biology Lab 2

Should we fear the flu virus spread?


Throughout the twentieth century there have been three major flu epidemics.

Between 1918-1920, the so-called English flu . It is the first time that a mutation appears influenza A (H1 N1). Infected 20% of the population. He could have killed fifty million people, between 2.5 - 5% of the population of Earth. Probably originated in China or the United States.

In 1957, the so-called Asian flu . Caused by another subtype, the A (H2N2). It originated in China. Caused about a million dead, mostly from secondary bacterial pneumonia. Mainly affected the elderly.

In 1968-1970, other flu originated in China, Hong Kong. Was caused by a new subtype, the A (H3N2), probably a genetic recombination with other viruses of avian origin.


World War I ended in 1918 with 10 million dead. English flu that year killed 40 to 50 million people when it had been difficult to pinpoint, some have raised the figure to 100 million -. It was the worst of the three global flu epidemics of the twentieth century, and in fact the worst pandemic of any kind in history. The virus that caused no came from pigs, but the birds, but it was H1N1, like the present. The H1N1 virus was a bird until 1918, and was the English flu who became a typical human strain.

As the English press was not subject to the restrictions of the war and reported on the flu, the Allies began to call the English flu pandemic. The first case occurred at Camp Funston (Kansas) on March 4, 1918. Only caused a mild respiratory disease, though highly contagious, like any flu. In April and had spread throughout North America and, aided by American troops throughout Europe. The second wave

mortal began Aug. 22 in Brest, France, port of entry for U.S. soldiers. It was the same virus, but sometime in the summer, became mortal. Those affected by the first wave were immunized. Causing pneumonia and died two days after the first symptoms. The flu may have killed 25 million people in the first 25 weeks, for comparison, AIDS killed 25 million in the first 25 years.

The 1918 virus had no gene for human type : it was a bird flu virus, but with 25 mutations that distinguished it from an avian influenza virus common. The virus of English flu multiplied 50 times more than the flu after a day of infection, and 39,000 times more after four days. In laboratory tests kill all mice in less than a week.

The rapid spread of the disease might be due to the massive movements of troops and modern transportation systems, as well as weakening by the stress of combat and chemical attacks. The remedies used to be home. For example, in the village of Pinar de Rabanera Burgos, it was with so-called O pills, syrup, homemade medicine, mallow flower, chamomile or tea.


The World Health Organization (WHO) urges "prepare for a pandemic." To occur would be mild , but warned that the so-called English flu of 1918, which killed millions of people, also began hesitantly.
"I think we must be aware and respectful of the fact that influenza moves in ways that we can not predict ."
Perhaps the biggest problem with which we are now is that of the exaggeration.

This quote from a doctor who fought with the English flu in 1918 can reassure
"Facts have shown that mortality from this disease is primarily a question of medical and financial resources. In villages where the epidemic was raging ... sufficed the arrival of new medical ... (Y) a few thousand pesetas ... to immediately changed the appearance of the disease, has revived confidence and reduced the proportion of severe and fatal cases.
Ángel Sánchez de Val, influenza Sepsis (Cartagena, 1919).