Investigators say they don't expect to find the specific sources of fatal strains of E. coli that killed two children in the Pacific Northwest and left a Washington boy fighting for his life.
Dr. Paul Cieslak, medical director of the communicable disease section of the Oregon Health Authority, said Thursday they need at least twice as many cases to pin down a source, which might be tainted food, lake water, or contact with livestock.
Relatives have said 4-year-old Serena Profitt of Otis, Oregon, and 5-year-old Brad Sutton fell ill after a family gathering in Lincoln County on the Oregon Coast. Serena was declared brain dead Monday at a Portland, Oregon, hospital.
Brad was upgraded to serious condition at Mary Bridge Children's Hospital in Tacoma, Washington, spokeswoman Marce Edwards said.
Dr. Greg Stern, health officer of Whatcom County, Washington, said those cases are not related to that of 3-year-old Brooklyn Hoksbergen of Lynden in northwest Washington. She died a week ago in a Seattle hospital.
Stern and Cieslak said the families of the victims have been interviewed, and a variety of potential sources of E. coli were identified, but no specific sources have emerged. The bacteria can incubate for 10 days in a victim before they show symptoms, allowing for a wide range of sources, which can only be narrowed down through matches between multiple victims.
All three children had a potentially fatal strain of E. coli, Stern and Cieslak said.
Results have yet to come back on a kind of DNA fingerprinting test of the E. coli, which can then be compared to the Centers for Disease Control and Prevention's national database.
If the three strains match, or match other strains, that could provide clues in tracking down a cluster of cases and a source, Cieslak said.
Young children and the elderly are particularly at risk of dying from E. coli. Cieslak said Oregon has had 21 fatal cases of E. coli since 1992, of which seven were under the age of 5, and 10 were over the age of 70.
Victims can die from kidney failure or bleeding in the brain.