Population-based surveillance for Vero cytotoxin-producing Escherichia coli
(VTEC) O157 has been carried out in Wales since -1990. The annual incidenc
e has remained stable during the 9-year period (mean: 1.6 cases per 100,000
population); the rate is highest in children younger than 5 years of age.
Blood in the stool is reported in fewer than half the cases, indicating the
importance of screening all fecal specimens for VTEC O157.