bacteria , '' said Skylar McElhaney , a spokeswoman for the Oklahoma Department of Environmental Quality . The Oklahoma Department of Health will analyze them and compare them with samples taken from victims , she said . `` We ca n't say for sure that it is tied to the water in any way , but we also can not rule it out , '' she said . Symptoms of infection with the bacteria can include severe diarrhea , bloody diarrhea , vomiting and severe abdominal cramping , said Larry Weatherford of the Oklahoma State Department of Health . Management at the restaurant , which has closed during the investigation , was working closely with health officials , he added . Meanwhile , the outbreak appears to be abating . `` While we believe we are seeing a downward curve in the number of people who have become ill , we still have many challenges with some patients who remain hospitalized , '' said State Epidemiologist Dr. Kristy Bradley . `` We continue to ask the public to be extra diligent in their hand washing and food preparation to minimize the possibility of additional persons becoming ill . '' The
-LRB- CNN -RRB- -- Oklahoma health officials said Friday they are searching for the source of a rare form of E. coli that has killed one person and sickened 116 others in the northeastern part of the state . The subtype of bacteria -- called E. coli 0111 -- is `` not normally found in this form of outbreak , '' said Leslea Bennett-Webb , director of communication for the Oklahoma State Department of Health . More than 50 people have been hospitalized and nine people -- six of them children -- have been placed on dialysis , she said . She said the federal Centers for Disease Control and Prevention in Atlanta , Georgia , helped state officials determine the subtype , but said the cause of the outbreak remains unknown . `` The focus has been narrowed to the Country Cottage Restaurant located in Locust Grove , '' she said , noting that most of the people who became ill ate there between August 15 and August 23 . Tests carried out on water from a well on restaurant property indicate the presence of bacteria , but `` we have not been able to confirm what kind of