Podcast Summary: MilliporeSigma – The Importance of E. coli and STEC Testing to Food Safety

Podcast: Food Safety Matters
Host: Food Safety Magazine
Guests: Sally Powell Price & Justice Jedlica, MilliporeSigma
Date: December 19, 2024

Overview

In this episode, the Food Safety Matters team dives into the persistent challenges posed by E. coli—especially Shiga toxin-producing E. coli (STEC)—within the food industry. Editorial director Adrienne Blum speaks with MilliporeSigma’s Sally Powell Price and Justice Jedlica, exploring the biology and epidemiology of these organisms, the evolving regulatory environment, economic consequences for manufacturers, best practices for detection, and technological innovations shaping the future of food safety testing.

Key Discussion Points & Insights

1. Why E. coli and STEC Remain Critical Food Safety Concerns

• Biology of the Organism

  • STECs are robust, ubiquitous in nature, especially in reservoirs like cows and ruminants, and very difficult to eradicate.

    “It’s going to be impossible to eradicate. It’s always going to be there in some form.”
    —Sally Powell Price [03:34]

  • Multiple pathotypes with different virulence genes exist (e.g., O157:H7, O26, O45, O103), impacting the severity of human illness.

• Public Health Impact

  • Estimated 100,000 illnesses/year (documented) in the US from STEC O157:H7 and non-O157; real numbers believed higher due to underreporting.

    “We’re looking at almost 200,000 illnesses a year, and that’s probably grossly underreported.”
    —Sally Powell Price [05:42]

• Economic Impact

  • Outbreaks and recalls can cost companies millions and damage brand trust.

    “A recall can run anywhere up to $10 million per recall or more...That can really take a company under.”
    —Justice Jedlica [08:48]

  • Food safety is both a supply-chain and consumer-level challenge, requiring shared responsibility from industry and households.

• Changing Epidemiology

  • Outbreaks not limited to traditional vehicles like beef and dairy; increasing incidents in produce (carrots, onions, leafy greens).

    “It’s cropping up in commodities that were not as prevalent years ago...not having a kill step, not having a sanitizing step...”
    —Sally Powell Price [10:38]

2. Food Safety Regulations Addressing E. coli and STEC ([12:46]–[17:49])

• Regulatory Landscape

  • USDA regulates meat and beef, FDA oversees ready-to-eat products and produce.
  • The system is risk-based rather than purely prescriptive, primarily resting on FSMA (Food Safety Modernization Act).
  • Regulation focuses on high-profile serotypes, e.g., E. coli O157:H7 as an adulterant in beef, with zero-tolerance and strict limits for other commodities.

• Need for Continuous Assessment

  • Regulations evolve with new risk evidence, e.g., the FDA’s Leafy Greens STEC Action Plan.
  • Risk-based frameworks allow producers to adapt controls as threats change.

    “Maybe always working isn’t always working...It allows you that opportunity to reassess what was going on.”
    —Justice Jedlica [15:43]

3. Testing Methods for E. coli and STEC ([18:18]–[21:27])

• Diverse Testing Approaches

  • Culture-based methods: selective agar, confirmation steps.
  • Rapid molecular (PCR) methods targeting virulence genes (stx, eae) for presence/absence and quantification.
  • Lateral flow "pregnancy-style" tests for toxins—simple and intuitive.
  • In situ hybridization (RNA probe) methods for fine-scale detection.

    “E. coli, luckily for us, is easy to culture...The two methods that I’d say are most familiar to folks are culture-based methods and rapid molecular PCR methods.”
    —Sally Powell Price [18:43]

• Choosing the Right Method

  • Depends on purpose: screening, compliance, periodic monitoring.
  • Validations and certifications are critical—reference FDA BAM, USDA MLG, Health Canada Compendium, AOAC, AFNOR, Microval.

    “Any method you do use, it’s really important to ensure that it’s validated, it’s robust, it’s fit for purpose.”
    —Sally Powell Price [20:38]

4. MilliporeSigma’s Product Suite for STEC Detection ([21:27]–[25:09])

• Range of Offerings

  • Sample/media prep: ReadyStream system.
  • Selective and chromogenic agar plates specifically for E. coli/STEC.
  • Certified reference strains (via Vetroids line).
  • Rapid tests (Single Path E. coli O157 kit) and in situ hybridization (HybridScan).
  • High-accuracy PCR platforms—GDS Assurance kits for both “top seven” and “big six” STEC strains.

    “No matter if you’re using them for screening or for confirmatory testing...we have a solution for you.”
    —Justice Jedlica [21:36]

• Emphasis on Validation

  • Full suite of certifications (AOAC, AFNOR, Microval, FDA BAM/USDA MLG compliant).

    “We have some really great certifications, validations for our products to help kind of take that onus off you...”
    —Sally Powell Price [24:30]

5. Industry Trends & The Future of Pathogen Detection ([25:37]–[29:09])

• Emerging STEC Pathotypes

  • With climate change, supply chain shifts, “other pathologies of E. coli” are expected to arise.

    “There are probably more [non-O157 STECs] out there that we haven’t properly sequenced or had our eyes on...”
    —Sally Powell Price [25:42]

• Technological Innovations

  • AI and digital data analytics for predictive testing, risk mapping (e.g., using satellite imagery for agricultural runoff).
  • Whole genome sequencing more accessible for finer differentiation of outbreak strains.
  • Novel detection approaches, including liquid crystal technologies and “electronic noses” adapted from perfumery to sniff out E. coli in meat.

    “They’re taking the electronic noses...and setting it up on the lines at meat companies and trying to see if they can smell E. coli.”
    —Justice Jedlica [27:57]

6. Recommended Resources for Practitioners ([30:29]–[32:20])

• Official Agency Resources

  • FDA’s E. coli webpage and the Leafy Greens STEC Action Plan.
  • FDA BAM Chapter 4A (E. coli).
  • USDA resources on verification activities for STEC in beef products.

• MilliporeSigma Resources

  • Dedicated web pages on food and beverage microbiology testing.

  • White papers, and brochures on STEC testing in beef, dairy, and vegetables.

    “FDA and USDA have done a tremendous amount of work pulling together very, very useful resources.”
    —Justice Jedlica [30:32]

Notable Quotes and Memorable Moments

• “It’s going to be impossible to eradicate [STEC]. It’s always going to be there in some form.”
  – Sally Powell Price [03:34]

• “A recall can run anywhere up to $10 million per recall or more...That can really take a company under.”
  – Justice Jedlica [08:48]

• “With all this recent outbreaks with the carrots, with the onions, having the McDonalds...I, you know, I love some holiday McDonalds. So, you know, just being careful and knowing what to eat and that you can eat it and feeling safe around your food, I think is really the true economic impact...”
  – Justice Jedlica [06:51]

• “They’re taking the electronic noses that perfumers and flavorists use...and trying to see if they can smell E. coli to find a more rapid way of detection.”
  – Justice Jedlica [27:57]

Important Timestamps

| Time | Segment/Topic | |-----------|-----------------------------------------------------------------------------| | 03:34 | Why E. coli/STEC are persistent food safety threats | | 05:42 | Underreporting and public health impact | | 08:48 | Economic impact of recalls | | 10:38 | Outbreaks shifting to produce commodities | | 12:46 | Regulatory structure and risk-based approach | | 18:18 | Overview of current testing methodologies | | 21:27 | MilliporeSigma’s suite of STEC testing products | | 25:37 | Future trends—emerging threats and new detection technologies | | 27:57 | "Electronic noses" for E. coli detection in meat | | 30:29 | Recommended resources for further information |

Conclusion

This episode underscores the complexity of controlling E. coli and STEC in the modern food system, highlighting the organism’s adaptability, economic and regulatory challenges, and the ongoing evolution of testing technology. MilliporeSigma’s representatives offer both technical insight and practical advice, demonstrating how industry, innovation, and regulatory vigilance must combine to safeguard public health.

For further reading, listeners are pointed toward federal regulatory resources and MilliporeSigma's technical content, with an encouragement to stay vigilant as the landscape—and the pathogens—continue to evolve.