Shiga Toxins, EIA with Reflex to E. coli O157, Culture - STEC causes foodborne and waterborne diarrheal disease worldwide which, if left undiagnosed, can progress to hemorrhagic colitis and/or hemolytic uremic syndrome (HUS). Since certain treatments and medications can increase the risk of HUS, prompt detection is necessary to prevent outbreaks and secondary transmission. STEC produces either one or both Shiga toxins (Stx1 and/or Stx2), both potent cytotoxins. By detecting the toxins, an EIA can detect STEC present in fecal samples or culture, regardless of the serotype or other virulence factors.