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I started this project about the flu, because I always wanted to know how does the flu attack you, why I got the flu the year when I did not take the shot, and I got the flu even the year I took the shot. Is there any medicine orally that would prevent the flu? ... Because the virus is so unusual, few if any people will have built-in immunity from past exposures. Even the vaccinated have no defense; flu shots shield against influenza variants that health experts have anticipated will be active in a given flu season, not against other, unforeseen kinds. Cases of flu are found worldwide were the worst epidemic, or pandemic, on record struck was in 1918 and killed more than 20 million people, sometimes within hours after the first symptoms appeared. This disaster, traced to the so-called Spanish influenza virus, was followed by epidemics of Asian flu in 1957, Hong Kong flu in 1968 and Russian flu in 1977. ... If a virus as deadly as that Hong Kong strain tore through the world’s crowded communities today, 30 percent of the earth’s population could conceivably be dead (from the virus itself or from secondary bacterial infections) before a vaccine became available to protect those who initially managed to escape infection.
There are two drugs being tested in large clinical trials that could be approved for sale as new missiles in the fight against the flu. ... these drugs have been designed to attack the influenza virus directly. ... Therefore, individuals treated in the first phases of an epidemic can spread a drug-resistant version of the virus to other people, who will then prove unresponsive to the medicines. ... When any virus causes disease, it does so by invading selected cell types, replicating within those cells and then pouring out of the cells to infect others symptoms arise both because viral proliferation disrupts the colonized cells and because the immune system attempts to contain the infection, in the process causing local inflammation and systemic
aches and fever. ... Historical descriptions based on symptoms indicate that flu epidemics have probably plagued human populations since well before the 5th century B. ... For a single copy of an influenza virus, or particle, to enter a human cell, hemagglutinin on the virus must link to a sugary molecule, sialic acid, on the surface of the cell
By the 1960s, investigators were well aware that a drug able to block any step in the replication process might prevent the virus from causing disease or might curtail an existing infection. ... Moreover, biologists realized that because influenza viruses grow inside cells and make use of the cells’ own protein-making machinery, most agents able to destroy the virus would also disturb healthy cells.
An influenza strain can produce a local or global epidemic only if the people exposed to the virus lack adequate immunity to it. For instance, when someone has the flu, the immune system produces molecules known as antibodies that recognize specific segments of hemagglutinin and neuraminidase on the viral surface. If the person is later reexposed to the same strain, these antibodies (primarily those directed at hemagglutinin) bind promptly to the virus and prevent it from causing a repeat infection.
Approximate Word count = 2636
Approximate Pages = 10.5
(250 words per page double spaced)
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