This is a rather strange question as it asks the committee to lump parkinsonism (a.k.a. conditions with Parkinson's-like symptoms) in with idiopathic Parkinson disease. Not too surprisingly, "the committee noted that Parkinson's disease is a diagnosis of exclusion". In fact, various conditions with Parkinson's-like symptoms must be excluded when making a differential diagnosis of idiopathic Parkinson's disease! Oddly, rather than recommending that the VA create a new category called parkinsonism under which idiopathic Parkinson Disease and "various conditions with Parkinson's-like symptoms" would all have been logically covered, the committee instead concluded that "there is no rational basis for exclusion of individuals with Parkinson's-like symptoms from the service-related category denoted as Parkinson's disease. To exclude a claim for a condition with Parkinson's-like symptoms, the onus should be on the U.S. Department of Veterans Affairs (VA) on a case-by-case basis to definitively establish the role of a recognized factor other than the herbicides sprayed in Vietnam."
Keep in mind, that Progressive Supranuclear Palsy (PSP) is an idiopathic neurodegnerative disease with Parkinson's-like symptoms. Although it has recently been linked to environmental factors there is no evidence that exposure to any specific chemical causes PSP. Manganese exposure, which can occur among welders, is associated parkinsonism as well. So we have an example of an idiopathic neurodegenerative disease and a neurotoxic effect that both produce Parkinson's-like symptoms that must logically be excluded in the differential diagnosis of idiopathic Parkinson's disease and yet, these two conditions will now be "included" in the category denoted as Parkinson's disease.
So what doesa this all mean for Vets? In short, with respect to excluding persons with various conditions with Parkinson's-like symptoms the committee has recommended that for these claims the onus "should" be on the U.S. Department of Veterans Affairs to establish the role of a recognized factor other than the herbicides sprayed in Vietnam on a case by case basis. In other words, if you have Parkinson's-like symptoms and the government can show that you were exposed to manganese while working as a welder after you completed your tour of duty they may be able to deny your claim. On the other hand, if you develop Parkinson's-like symptoms and there are no identifiable recognized factors other than the herbicides sprayed in Vietnam in your personal exposure history your claim may be paid.
Link to original story in EurekAlert