The deadly pattern of illnesses began to emerge in 2012 at hospitals in Seattle, Pittsburgh, Chicago. In each case, the culprit was a bacteria known as CRE, perhaps the most feared of superbugs, because it resists even “last defense” antibiotics and kills up to 40% of the people it infects.  And in each case, investigators identified the same source of transmission: a specialized endoscope (called a duodenoscope), threaded down the throat of a half-million patients a year to treat gallstones, cancers and other disorders of the digestive system.

Neither the scopes’ manufacturers, nor the FDA has issued any warnings regarding the device.  The FDA said  in a written statement to USA TODAY that it was “aware of and closely monitoring” the infection risks associated with the scopes. “Some parts of the scopes may be extremely difficult to access and clean thoroughly,” the agency adds, “and effective cleaning of all areas of the duodenoscope may not be possible.”

Lawrence Muscarella,  a biomedical engineer and independent consultant who advises hospitals on endoscope safety,  identified at least a half-dozen U.S. outbreaks of CRE and related superbugs since 2012 that were linked to contaminated duodenoscopes.

Several hospitals are not waiting for the FDA, and are instituting new safety procedures of their own.

Read more at the USA Today.