Tuesday, September 12, 2006



This results of this particular study have been a long time coming, and many researchers around the world will be stunned to learn that one of the most feared theories of how the current H5N1 avian influenza virus kills its human hosts has turned out to be true.

From the New York Times :

Avian flu kills in much the same way the global flu pandemic of 1918 did, by drowning victims in fluid produced in their own lungs, a new study has found. The study also suggests that immediate treatment with antiviral drugs is crucial, because the virus reproduces so quickly that, if not suppressed within the first 48 hours, it tends to push victims into a rapid decline to death.

“The paradigm ‘hit hard and hit early’ probably is very true for H5N1 influenza,” said Dr. Menno D. de Jong...

However, he added, because the body’s own immune response does part of the damage, doctors should consider giving anti-inflammatory drugs along with antivirals like Tamiflu.

This study, which appears in the October issue of Nature Medicine, was led by an Oxford research team in Ho Chi Minh City, Vietnam, and compared 18 people with the A(H5N1) avian flu in 2004 and 2005 to 8 people infected with seasonal human flus.

It found that the avian flu patients, and particularly the 13 who died from it, had unusually high levels of the virus in their bodies. Consequently, they also had high levels of the chemicals, known as cytokines and chemokines, that set off the immune system’s inflammatory response.

Those chemicals, some of which are produced in cells lining the narrowest passages in the lungs, draw in white blood cells to attack invaders. But doing so too vigorously can flood the lungs, causing deadly pneumonia.

The effect, known as the “cytokine storm” is the leading theory as to why so many young, previously healthy people died in the 1918-19 pandemic, known as the Spanish flu, which killed tens of millions of people.

Seasonal flus tend to kill the very old and very young, who usually die from bacterial infections that develop days after the milder flu virus has irritated their lung tissue.

The study also showed that some of the flu strains isolated in Vietnam had particular genetic changes that virologists have been watching for, fearing that these changes would make them more lethal.

Go here to read the whole story.

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