National Reference Center (NRC) for Shiga-toxin producing E. coli (STEC)

Important message (from 01.01.2025 onwards)

Epidemiological typing of STEC by WGS

Given the increase in the number of STEC-positive samples, from 01.01.2025 the NRC will perform typing by WGS only on a selection of strains.

The following strains will still be typed by WGS:

  • STEC strains positive for stx2 (with the exception of stx2f)
  • STEC strains from HUS cases
  • STEC strains from outbreaks
  • STEC strains belonging to serogroups O26 and O157

Note: WGS can be performed on request for criteria other than those listed above. Please contact the NRC for this purpose.

Risk classification of STEC

Strains containing the stx2f gene appear to be less pathogenic. From 01.01.2025, stx2f-positive strains will be reported in the low-risk category. Please refer to the ‘Systematic typing & risk classification of STEC isolates’ section for more information.

General considerations on the diagnosis of STEC infections

Shiga toxin-producing E. coli (STEC) are a major cause of gastrointestinal infections worldwide. STEC infection usually results in mild to bloody diarrhoea, but can sometimes progress to the life-threatening haemolytic uraemic syndrome (HUS).

Diagnosis of STEC infections is especially important for timely detection of outbreaks.  The NIHDI provides reimbursement for the detection of the most common STEC serotype O157:H7/H- under certain conditions. However, the NRC’s activities are not limited to detecting this serotype alone.

To detect outbreaks early, it is important to send stool samples to the reference laboratory in every case of haemolytic uraemic syndrome (HUS), even if O157 is detected locally (mixed infections are also possible). These cases then function as the ‘tip of the iceberg’ in surveillance and early detection of outbreaks, which can lead to identification and elimination of a source of infection.

Note over de benaming van deze micro-organismen:
Gedurende jaren heeft het NRC de voorkeur gegeven aan de benaming “verocytotoxine” voor het toxine en “enterohemorrhagische E. coli” voor het micro-organisme. Hoewel deze benamingen aanvaard blijven, ziet men in de literatuur meer en meer een neiging om zich te beperken tot “Shiga toxine” en “Shiga toxine-producerende E. coli (STEC)”, die vanaf nu door het NRC uitsluitend zullen worden gehanteerd.

Helpful links:

At the bottom of this page, you can find the NRC reports.

You can consult the accompanying epidemiological surveillance reports at: Health topic Pathogenic E. coli

Responsible laboratories

Coordinator

QR code

QR code for this page URL