National Shiga Toxin-producing E. coli (STEC) Surveillance

National Shiga toxin-producing Escherichia coli (STEC) surveillance data are collected through passive surveillance of laboratory-confirmed human STEC isolates in the United States. Clinical diagnostic laboratories submit STEC O157 isolates and Shiga toxin-positive broths to state and territorial public health laboratories, where they are further characterized.

State and territorial public health laboratories send reports of these STEC isolates electronically to the Centers for Disease Control and Prevention (CDC) using a variety of mechanisms. Data are collected into the Laboratory-based Enteric Disease Surveillance (LEDS) system, which is maintained by the Division of Foodborne, Waterborne, and Environmental Diseases (DFWED) in the National Center for Emerging and Zoonotic Infectious Diseases.

Annual summaries of these data are the national source of serotype information for STEC. Unusual or untypable isolates or Shiga toxin-positive samples from which no STEC can be isolated by the state or territorial public health laboratory are forwarded to CDC’s National Escherichia and Shigella Reference Laboratory in the Enteric Diseases Laboratory Branch (EDLB) in DFWED; results are reported back to the referring public health laboratory.