Another four cases of E coli O157 have been reported in connection to events on Jan. 17-19 at the SSE Hydro arena in Glasgow, bringing the total case count up to 15. Health officials believe the illnesses may be linked to contaminated burgers and are asking that anyone who attended the Hydro between Jan. 17 and 25, and has experienced stomach cramps, diarrhea, nausea and fever to contact their healthcare provider. “Investigations are ongoing and while there is no conclusive evidence our investigations have indicated that there may be a link to the consumption of burgers at the SSE Hydro,” said NHS Greater Glasgow and Clyde‘s Dr. Eleanor Anderson. “Glasgow City Council Environmental Health Officers are working closely with the vendors to ensure all appropriate food hygiene standards are being met.” All 15 cases are recovering at home. News of the outbreak was first reported on Jan. 31 when there were seven cases. An update on Feb. 3 reported that 11 people had been infected.