H5N1 Flu Poses Threat to Brain Health

As if the very high mortality rate of the H5N1 bird flu wasn’t enough cause for alarm, the August 18, 2009 issue of the Proceedings of the National Academy of Sciences of the United States of America (PNAS) carries a report that the H5N1 influenza virus may cause damage to the central nervous system. (Published online before print August 10, 2009, doi: 10.1073/pnas.0900096106 PNAS August 18, 2009 vol. 106 no. 33 14063-14068 http://www.pnas.org/content/106/33/14063)

H5N1 currently has a 61 percent mortality rate, that is, of the more than 400 confirmed cases, more than half proved fatal even with advanced medical treatment.

It is important to remember that this is NOT the same influenza stream as the current pandemic H1N1.

Testing in laboratory mice has shown that infection by A/Vietnam/1203/04 (H5N1) causes nerve damage which may trigger such diseases as Parkinson’s and Alzheimer’s in humans.

A report by St Jude’s Children’s Hospital researchers agree, “”This avian flu strain does not directly cause Parkinson’s disease, but it does make you more susceptible,” said Richard Smeyne, Ph.D., associate member in St. Jude Developmental Neurobiology. Smeyne is the paper’s senior author.

“Around age 40, people start to get a decline in brain cells. Most people die before they lose enough neurons to get Parkinson’s. But we believe this H5N1 infection changes the curve. It makes the brain more sensitive to another hit, possibly involving other environmental toxins,” Smeyne explained.”

The 1918 “Spanish Flu” (also an avian influenza strain) was related to some later development of Parkinson’s.

Fortunately, the same researchers say that the current pandemic threat, H1N1, poses LOW neurologic risk.

Scientists and researchers are highly concerned about the potential spread of H5N1 and are closely monitoring the virus for indications that it might mutate into a form which is easily spread between humans – so far there is only very limited evidence of this and it has not spread widely.

St. Jude Children’s Research Hospital

St. Jude Children’s Research Hospital is internationally recognized for its pioneering work in finding cures and saving children with cancer and other catastrophic diseases. Founded by late entertainer Danny Thomas and based in Memphis, Tenn., St. Jude freely shares its discoveries with scientific and medical communities around the world. No family ever pays for treatments not covered by insurance, and families without insurance are never asked to pay. St. Jude is financially supported by ALSAC, its fundraising organization.