Swine flu Deaths-Viral Pneumonia | Arthritis Information

http://www.nytimes.com/2009/05/09/health/09flu.html?ref=health

Some of the serious cases involve healthy young people, and the reasons for that are still unexplained. Many of the patients went into rapid decline and died of viral pneumonia, not bacterial pneumonia, said Dr. Sylvie Briand, a W.H.O. flu expert. Viral pneumonia may be a result of the “cytokine storm,” in which the body’s own immune reaction to a new virus floods the lungs with fluid. It can progress faster and be harder to treat than bacterial pneumonia.

Interesting! Although this is one of those hotly debated press releases (additionally it is several days older than the article above, it too indicates "A cytokine storm occurs when the body's immune system over-reacts to an intruder, such as a virus, by producing high levels of cytokines, which are signaling chemicals that help mobilize immune cells capable of removing infectious agents from the body. When too many cytokines are produced, they can stimulate an inflammatory response in which the accumulation of immune cells and fluid at the site of infection may prevent affected tissues and organs such as the lungs from functioning properly and may even cause death.

Some influenza viruses can cause an unusually high proportion of deaths among healthy young adults with well-functioning immune systems who become infected, possibly due to this cytokine storm phenomenon. This phenomenon may also explain why the Spanish influenza pandemic of 1918, for example, was also particularly deadly for young healthy adults.

David L. Woodland, PhD, Editor-in Chief of Viral Immunology, and President and Director of the Trudeau Institute, Inc. (Saranac Lake, NY), emphasizes that much is still not known about the current influenza outbreak and the human/avian combination virus causing it. "We do not know how long ago this virus emerged, how deadly it is, whether it has pandemic potential, how the severity of infection relates to patient age, and why some infected patients die—whether a cytokine storm is responsible for these deaths," says Woodland."