Friday, March 24, 2006



Late last year, the World Health Organisation predicted a human pandemic of avian influenza could kill more than 140 million people. Two weeks back, an acclaimed virologist told ABC News in the US that a human pandemic could kill half the world's population, 2.5 billion people.

Another week, another estimate. This time....well, hardly any at all.

From The Sydney Morning Herald :

"Scientists have discovered why the H5N1 avian flu that is so lethal in birds has not spread easily among humans.

"Unlike flu viruses that are passed easily between people, H5N1 has a hard time attaching to cells in the nose, throat and upper airways. However, it readily attaches to cells deep in the lungs.

"This suggests that people need close and heavy exposure to the H5N1 virus for it to get into the lungs, where it can take hold. But once there, it causes extensive damage to the machinery of respiration - the cells and air spaces where oxygen is exchanged for carbon dioxide.

"'For the viruses to be transmitted efficiently, they have to multiply in the upper portion of the respiratory system so that they can be transmitted by coughing and sneezing,' said Yoshihiro Kawaoka, a virologist at the University of Wisconsin-Madison, who led the research team.

"People infected with the virus, which has spread from Asia to Europe, the Middle East and Africa, have had close contact with diseased birds. Scientists fear the virus could mutate into a pandemic strain that could become highly infectious and capable of killing many millions of people.

"'Our findings provide a rational explanation for why H5N1 viruses rarely infect and spread from human to human, although they can replicate efficiently in the lungs,' Dr Kawaoka and his team said in a report in the journal Nature.

"Dr Kawaoka and researchers in Japan infected human tissue with bird flu viruses. Their findings suggest that strains of H5N1 circulating in birds would have to undergo several key genetic changes to become easily transmissible in humans."

But those genetic changes haven't yet occurred, though there is still plenty of people who claim this could happen any day. The more we learn about the human form of avian influenza, the more it seems the panic may be completely unnecessary.

It's a dangerous virus, no doubt at all, but the rush to scare the living Christ out of people, and to spend billions of dollars on anti-virals, has become a shameful exercise and, more than likely, a terrible waste of money that could have been better spent trying to save the lives of people who are already dying from infectious diseases the world over. Millions and millions of people each year.

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