In a previous study, 10,617 veterans who underwent the procedure at four VA hospitals in Tennessee, Georgia and Florida were exposed to the risk of viral infection from improperly sterilized equipment, Duncan said.
Of the 96 percent who have responded, 13 tested positive for hepatitis B, 34 to hepatitis C -- both of which are liver diseases -- and six tested positive for HIV, the AIDS virus, he said.
It's not clear how they were infected, whether via the scopes or some other way. But Buyer urged that veterans not be forced to try to prove that that they got the virus from dirty equipment rather than from some other exposure.
"My opinion is that the benefit of the doubt will go to the veteran," he said.