Federal health officials are laying out extra safety measures that hospitals can take to clean specialized medical scopes that have been linked to sometimes deadly bacterial outbreaks across the U.S. 

However, Food and Drug Administration officials acknowledge that not all hospitals have the staff, expertise and resources to take the steps, including sterilizing scopes with toxic gas to kill bacteria. Even after those steps "the risk of infection transmission cannot be completely eliminated."

Despite the risks, the FDA says devices should remain available because they benefit "appropriately selected patients."

Known as duodenoscopes, the scopes consist of a flexible tube that surgeons guide into the digestive tract to diagnose and treat blockages of the bile and pancreatic ducts. They are used in an estimated half-million procedures per year.