A DESCRIPTIVE STUDY OF VEROCYTOTOXIGENIC ESCHERICHIA-COLI (VTEC) CASES REPORTED IN ONTARIO, 1990-1994

Characteristics of VTEC cases identified through routine surveillance in Ontario between 1990 and 1994 are described. Information was extrac ted from Reportable Disease Information system (RDIS) of Ontario and w as evaluated for its completeness and internal validity. A total of 2, 441 VTEC cases were identified for the five-year study period correspo nding to an average annual rate of 4.8 cases per 100,000. Sixteen deat hs were recorded. Bloody diarrhea was reported for 546 patients (40%) and was the most frequently reported symptom. For most cases, the home was recorded as the likely risk setting (36%). Food was incriminated as the source of infection for more than 36% of cases. Nine (69%) of t he thirteen data fields compulsory for transmission to the Ontario Min istry of Health had less than 10% of combined missing and unspecified values. Fields describing risk factors had greater than 56% of entries missing or unspecified.