South Korean medical doctors said Sunday that a South Korean patient in 2004 was treated for the same strain of stomach virus that has recently led to the deadly food poisoning outbreak in Europe. Professors Bae Yoo-kyun at Chonnam National University Hwasun Hospital and Jang Hee-chang at Chonnam National University Hospital said the 29-year-old woman was hospitalized after suffering stomach pains and internal bleeding. She was diagnosed with hemolytic-uremic syndrome (HUS), which is normally caused by enterohemorrhagic E. coli (EHEC) O157:H7. But doctors later found a different strain, E. coli O104:H4, in her stool sample, South Korea\'s (Yonhap) news agency. It is the same virus that has killed at least 18 people and sickened some 1,600 others across Europe. Doctors said the South Korean patient was released after four weeks of treatment. Bae has written a paper on the case and it was published in a medical journal in 2006. \"The patient had eaten a hamburger and first she was treated for diarrhea,\" Bae said. \"Her symptoms got worse, and they were more serious than usual symptoms for typical E. coli infection.\" Jang said this was the first paper in the world to claim that the EHEC O104 strain could also cause HUS. \"No major research on E. coli followed that paper,\" Jang said. \"And there\'\'s not been any outbreak before the recent one in Europe.\" Asked if this was a mutant virus, Jang said he would have to compare the Korean case with other E. coli cases. \"There are different kinds of O104:H4 and they seem to have particular genes that cause HUS,\" the professor said.