Luckily, the H1N1 ("Swine Flu") virus, while pandemic, does not appear to have some of the side effects of other possibly pandemic strains. Researchers are now showing that at least one strain of the H5N1 ("Bird Flu") avian influenza virus leaves survivors at a significantly increased risk for Parkinson’s disease and possibly other neurological problems later in life. This is according to new research from St. Jude Children’s Research Hospital.
In the August 10 online early edition of the Proceedings of the National Academy of Sciences, researchers reported that mice which survived infection with the avian flu strain were more likely than uninfected mice to develop brain changes associated with neurological disorders like Parkinson’s and Alzheimer’s diseases. Both Parkinson’s and Alzheimer’s involve a loss of brain cells crucial to a variety of tasks, including movement, memory and intellectual functioning. The study revealed the H5N1 flu strain caused a 17 percent loss of the same neurons lost in Parkinson’s as well as accumulation in certain brain cells of a protein implicated in both diseases.
“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 and 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.
Should the avian flu virus mutate to a pandemic variety including human-to-human transmission it could possibly leave a huge increase of Parkinson's and Alzheimer's cases in its wake.