STEC confirmation testing

ESR’s role in the meat export market is critical in assisting with the clearance of meat exported to the United States.

To retain New Zealand’s access to the United States’ multi-billion-dollar meat market, our meat has to be tested and cleared for a range of pathogens.

Most E. coli are harmless and are actually an important part of a healthy human intestinal tract. However some E. coli are harmful. The Shiga toxin-producing E. coli (STEC) cause disease by producing a toxin, the most common serotype being E. coli O157.

In 1994, E. coli O157 was classified as adulterant in beef products under US Federal Meat Inspection Act. This meant that countries wanting to export meat to the US had to put in place a screening programme for this pathogen. The Enteric Reference Laboratory (ERL) at ESR has been providing this service since 1998.

In June 2012, the US introduced a new set of regulations prohibiting the presence of six additional STEC serotypes in beef products referred to as the Top 6 (i.e. O26, O45, O103, O111, O121, and O145), creating a “Top 7” group of adulterants.

If found these can cause meat to be rejected and suspicion cast over the safety of the source in the future. Not all strains of these “Top 7” STEC carry the genes to produce the toxins, so it is up to ESR to carry out the confirmatory testing that categorically shows whether the meat is “safe” or not. Confirmatory and characterisation testing for the Top 7 is acknowledged world-wide to be scientifically complex, challenging, and is still in its infancy.

The ERL is uniquely (and solely) positioned in New Zealand to undertake the international reference level confirmation and characterisation for the Top 7 E. coli groups at standards that are demanded by the United States and other countries.

How to submit samples for O157, Super 6 & 7 Testing

Primary screening laboratories, please use the STEC confirmation sample submission form [PDF, 39 KB]

  • The following vials from Thermo Fisher Scientific are strongly recommended to avoid samples leaking and to ensure the safety of staff handling the samples: 30 ml PC (Poly-carbonate) flat base, Natural screw cap, cat# LBS3688.
  • Please make sure that the samples are clearly labelled and if necessary seal the lid with parafilm (not sellotape).
  • We require a minimum of 10 ml for Super 6/7 testing.
  • If leaking vials are delivered to ESR, we will NOT be able to process them, as this exposes our staff to an unacceptable health and safety risk.

During the Bobby calf season weekly testing reports for clients are published on this secure site (external link) .

Please email us for access or for any questions on STEC confirmation testing.