Water is a suspect for five E. coli O157:H7 cases in Livingston County, New York that are related, but tests so far have turned out to be negative. That leaves health officials in western New York State with a bit of a mystery. As first reported on Aug. 20, 7 people in Livingston County were stricken with E. coli infections; 4 required hospitalization. The onset of confirmed illnesses was recorded between Aug. 6 and 24 with those infected being from age 22 to 67. Health officials were able to identify a common outbreak strain for 5 of the 7 cases. Water in the geographic area where victims live has tested negative for E. coli contamination. While all 7 cases are geographically clustered, health officials said they do not all share the same source of public water. That includes the 5 cases linked with the common strain. Livingston County Public Health Director Joan Ellison says the investigation is only at its halfway point and the possibility of water being a common source has not yet been ruled out. Ellison Monday renewed a public health warning for Livingston County. The alert reminds the public that severe and persistent diarrhea, some bloody, are among the classic symptoms for E. coli infection. The warning also makes it clear that while E. coli is a pathogen that is is harbored in the intestines of animals and normally transmitted through feces, it can also be spread by other means including by washing fruits and vegetables.