Insights from 30 years of Salmonella proficiency te…(EAP)

Performance trends from three decades of AXIO PT data

Insights from 30 years of Salmonella proficiency testing

Authors: Tracey Noblett and Joe Lackey

lgcstandards.com/AXIO

Insights from 30 years of Salmonella proficiency testing

This whitepaper examines long-term trends across this dataset, presents a detailed atypical-strain case study, and compares AXIO PT findings with other major international PT programmes. We highlight recurring challenges such as atypical phenotypes, matrix-linked recovery issues and low-level contamination. We also show how analyst-level review over multiple PT rounds using AXIO’s PORTAL platform supports root-cause investigation, corrective actions and ongoing competency. Together, these insights demonstrate the central role of Salmonella PT in benchmarking capability, supporting accreditation and strengthening laboratory performance. Testing has distributed more than 200,000 Salmonella proficiency testing (PT) samples to laboratories in more than 160 countries, creating one of the world’s most extensive datasets on laboratory performance. With non-typhoidal Salmonella (NTS) causing nearly 100 million illnesses and more than 150,000 deaths each year worldwide , reliable detection across diverse food matrices remains essential for public health. Over three decades, LGC AXIO Proficiency

Introduction

The World Health Organisation estimates that unsafe food causes 600 million illnesses and 420,000 deaths each year , with surveillance data from the United States (US) and European Union (EU) consistently placing Salmonella among the leading causes of hospitalisation and economic loss. These figures underscore the need for robust detection across different foods and testing environments. Salmonella is taxonomically diverse, comprising two species, S. enterica and S. bongori. S. enterica contains six subspecies, with S. enterica subsp. enterica alone accounting for more than 1,500 serovars . NTS is acquired primarily from contaminated foods such as eggs, dairy, meat products and other fresh produce. Illness usually presents as gastroenteritis , although invasive disease occurs in around 5% of cases, particularly in young children, older adults and immunocompromised people . Outbreak investigations increasingly show that illness can follow ingestion of very low numbers of cells – sometimes as few as 10–100 cells – especially in high-fat, low-moisture foods that protect cells against gastric acid. These findings emphasise the need to assess laboratory detection capability across diverse matrices and physiological states, including low-level and stressed cells. Reliable detection depends not only on robust analytical methods but also on regular, objective assessment of laboratory performance. PT provides this independent check, evaluating end-to-end workflow capability under controlled but realistic challenge conditions. Because PT samples may include atypical phenotypes, low inoculum levels and matrix-linked recovery challenges, they can reveal vulnerabilities not captured by routine quality control. This whitepaper examines performance trends from three decades of AXIO PT data, and places them in context with findings from other major PT programmes. We highlight recurring drivers of poor detection and outline practical steps laboratories can take to strengthen Salmonella workflows.

Matrix properties strongly influence Salmonella survival and recoverability , which in turn affects the performance of any detection method. Key factors include water activity, pH, fat and protein content, solute load (e.g. salts and sugars), and intrinsic antimicrobials found in certain matrices such as herbs and spices. Physiological factors such as strain characteristics, growth phase and stress adaptation also play a role, while storage conditions (time, temperature, humidity) can further modify outcomes. As a result, strains that are readily detected in high-moisture matrices may be far more difficult to recover from low- moisture, high-fat or acidic foods . These biological and matrix-driven effects have direct methodological consequences, including differences in enrichment efficiency and colony development on differential or chromogenic agars , particularly when cells are stressed or injured. Matrix-relevant PT therefore provides a realistic appraisal of end-to-end workflow performance – from sample preparation and enrichment through confirmation and reporting. To ensure this assessment is meaningful, PT items should reflect the laboratory’s accredited scope under ISO/IEC 17025:2017 . For Salmonella detection, this means selecting PT samples that match routinely tested food matrices, ensuring performance is evaluated under conditions that reflect real-world analytical challenges. Matrix-relevant proficiency testing for Salmonella

Notable outbreaks:

2015 Cucumbers (Mexico), 907 cases, 6 deaths ( S. Poona )

2009 Peanut butter (USA), 714 cases, 9 deaths ( S. Typhimurium ); >3600 products recalled

2023 Cantaloupes (Mexico), 407 cases, 158 hospitalisations, 6 deaths ( S. Sundsval )

2013 Tahini (Turkey), 16 cases, 1 death ( S. Montevideo, S. Mbandaka )

lgcstandards.com/AXIO

Insights from 30 years of Salmonella proficiency testing

Microbiological criteria for Salmonella testing

Regulatory requirements reflect the strong influence of matrix properties on Salmonella survival and recoverability. These regulations specify presence/absence requirements or allowable numbers per sampling unit, and vary according to the food category, processing steps and intended use (ready-to-eat vs intended to be cooked). In most foods, Salmonella must be absent in the portion tested. A notable exception is carcass sampling, where subsequent processing steps are expected to reduce risk.

Evolution of detection methods

Over the past three decades, Salmonella detection has shifted markedly as laboratories have increasingly moved to automation and rapid methods . More than 100 validated methods are now available through AOAC International , Association Française de Normalisation (AFNOR) and the MicroVal certification scheme , and participant choices increasingly reflect this breadth. In the AXIO PT Salmonella testing dataset (digital records from 2009 onwards), PCR use increased from 7% to 19%, while traditional culture workflows fell from 49% to 31%. Chromogenic agars have also become more common, helping simplify colony identification. Despite these changes, performance shortfalls in the AXIO dataset were more often linked to atypical phenotypes than to the method selected. This reflects the stringent, matrix-specific validation requirements of the ISO 16140 series, under which presumptive positives must be appropriately confirmed using validated procedures. Confirmatory techniques have also advanced : traditional biochemical and serological tests are now frequently supplemented – or replaced – by MALDI-TOF MS and, increasingly, next-generation sequencing.

Salmonella detection methods used in AXIO PT schemes

Enrichment/culture ISO 6579 PCR VIDAS Chromogenic agar 3M Molecular Detection System DuPont BAX ELISA Rapid Test (Various) Other

0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50%

Nov 24 Sep 09

Monitoring trends and investigating poor performance

While most Salmonella results recorded within Axio PT schemes are satisfactory, ISO/IEC 17025 requires laboratories to investigate any unsatisfactory outcome. A single result rarely explains the underlying issue ; meaningful diagnosis comes from examining performance over multiple rounds, where patterns such as persistent bias, analyst variation or matrix-linked difficulties become visible. To support this assessment, AXIO provides participating laboratories with PORTAL , a data- analysis platform that collates performance across rounds, schemes and analytes. By visualising outliers, comparing methods and assessing analyst-level trends, PORTAL helps distinguish isolated events from consistent process weaknesses. The multi-year performance data that follow illustrate how Salmonella detection varies with matrix, strain and inoculum level. PORTAL provides the tools to interpret these patterns and identify the drivers of improvement.

Using PORTAL to monitor trends and investigate root causes

lgcstandards.com/AXIO

Insights from 30 years of Salmonella proficiency testing

Four years of Salmonella PT under varied conditions

The table below shows example data from the AXIO QCS Chocolate scheme over a four-year period. Inoculum levels ranged from 5–100 colony forming units per gram (CFU/g), with satisfactory performance varying from 64% to 100% per round. Most strains were typical, with only occasional atypical strains included. Tracking inoculum level, strain type and performance together enables comparisons across rounds and highlights how matrix properties influence recovery. Periodic negative samples confirm the ability to report true negatives and guard against default positive reporting.

Year Sample Round Contents

No. of results Level of target organism % correct Result Atypical

Same strain, different matrix

229

100

Pos

2015 712

Salmonella Oranienburg

2015 714

229

Pos

Salmonella Thompson

2015 710

233

Pos

Salmonella Oranienburg

2015 711

233

100

Pos

Salmonella Nottingham

2015 716

233

Escherichia coli ; Enterococcus faecalis ; Saccharomyces 76

<10

Neg

2016 714

233

Pos

Salmonella Panama

2016 710

237

100

Pos

Salmonella Stanley

Same strain, different levels

2016 711

237

100

Pos

Salmonella Thompson

2016 712

237

<10

Neg

Kocuria kristinae

2016 714

237

100

Pos

Salmonella Oranienburg; Enterobacter aerogenes

2016 710

241

Pos

Salmonella Livingstone

2016 711

241

Pos

Salmonella Oranienburg; Enterobacter aerogenes

2016 712

241

Pos

Salmonella Thompson

2016 714

243

Pos

Salmonella Thompson

2016 710

245

Pos

Salmonella Indiana

2016 711

245

100

Pos

Salmonella Indiana

2017 710

249

100

Pos

Yes

Salmonella Bredeney

2017 712

249

Pos

Salmonella Nottingham

2017 710

251

<10

Neg

Escherichia coli

2017 714

249

100

Pos

Salmonella Montevideo

Atypical strain

2017 710

253

100

Pos

Salmonella Bovismorbificans

253

Pos

2017 714

Salmonella Bracknell

2017 711

253

Pos

Salmonella Panama; Enterobacter cloacae

2017 712

253

100

Pos

Salmonella Manchester

2017 714

253

<10

Neg

Enterobacter aerogenes

2017 710

257

Pos

Salmonella Stanley; Citrobacter diversus

2017 711

257

100

Pos

Salmonella Manchester

2017 712

257

<10

Neg

Staphylococcus epidermidis

261

100

Pos

2018 710

Salmonella Manchester; Citrobacter freundii

261

Pos

2018 711

Salmonella Panama

Negative sample

261

100

Pos

2018 712

Salmonella Bovismorbificans

261

Pos

2018 714

Salmonella Stanley

2018 710

265

Pos

Salmonella Salford; Enterobacter aerogenes

265

100

Pos

2018 711

Salmonella Senftenberg

265

500

Neg

2018 712

Escherichia coli

265

Pos

2018 714

Salmonella Thompson

273

<10

Neg

2019 710

Citrobacter freundii

Typical Salmonella PT performance

Lab ID

Method

Results

MC6163

MKTT/RV + XLD + BGA 37

Detected

A typical performance report from PORTAL, round MC 305. Results are colour-coded: green indicates satisfactory performance and red indicates unsatisfactory. This sample contained Salmonella Livingstone at 8 CFU/g, with 99.7% of participants reporting a correct result – which is a little higher than the expected performance for this matrix and level. The summary graph (below) shows performance scores across Salmonella PT rounds over a five-year period. On average, around 96% of results are satisfactory. This rate is unchanged for negative samples: even when no Salmonella is present, approximately 4% of participants still report a false positive.

MC6177

MKTT/RV + XLD + BGA 37

Detected

MC6177

Other

Detected

MC6187

Other

Detected

MC6198

Other

Detected

MC6250 Enrichment/culture

Detected

MC6253

MKTT/RV + XLD + BGA 37

Detected

MC6421

MKTT/RV + XLD + BGA 37

Detected

MC6436 PCR

Detected

MC6440 MKTT/RV + XLD + BGA 37

Detected

MC6446 VIDAS

Detected

MC6446 PCR

Detected

MC6446 MKTT/RV + XLD + BGA 37

Detected

MC6447

Chromogenic agar

Detected

MC6447

PCR

Detected

100

MC6447

MKTT/RV + XLD + BGA 37

Detected

MC6476 MKTT/RV + XLD + BGA 37

Detected

MC6496 PCR

Detected

MC6524 VIDAS

Detected

MC6526 MKTT/RV + XLD + BGA 37

Detected

MC6645 Rapid test (Various)

Detected

MC6645 VIDAS

Detected

MC6651

Enrichment/culture

Detected

MC6679 Other

Not Detected

MC6722

MKTT/RV + XLD + BGA 37

Detected

Jan-15 Jan-16 Jan-17 Jan-18 Jan-19 Jan-20

MC6745

MKTT/RV + XLD + BGA 37

Detected

MC6750 Other

Detected

Incorrect results 4%

MC6767

ELISA

Detected

MC6798 PCR

Detected

MC6838 PCR

Detected

MC6838 MKTT/RV + XLD + BGA 37

Detected

Correct results 96%

MC6838 Other

Detected

MC6900 Other

Detected

MC6934 Other

Detected

MC6946 MKTT/RV + XLD + BGA 37

Detected

MC6948 VIDAS

Detected

MC7099 MKTT/RV + XLD + BGA 37

Detected

MC7109 3M Molecular Detection System

Detected

MC7112

Chromogenic agar

Detected

MC7135

MKTT/RV + XLD + BGA 37

Detected

MC7173

VIDAS

Detected

MC7299 MKTT/RV + XLD + BGA 37

Detected

MC7438 3M Molecular Detection System

Detected

MC7490 VIDAS

Detected

MC7521

VIDAS

Detected

MC7729 Rapid test (Various)

Detected

MC7729 VIDAS

Detected

MC7729 MKTT/RV + XLD + BGA 37

Detected

MC7732

Enrichment/culture

Detected

MC7756 Other

Detected

MC7757

Other

Detected

lgcstandards.com/AXIO

Insights from 30 years of Salmonella proficiency testing

Case study: investigation of unsatisfactory performance

PT schemes occasionally include low-CFU samples and atypical strains, to challenge detection workflows under realistic conditions, as required by ISO 17043. These challenges can reveal weaknesses that may not be apparent in routine testing, and performance occasionally falls below expected levels. In the oatmeal matrix round MC 267 (July 2018), for example, only 86% of participants reported the correct result.

Round MC 267 – Food Microbiology QMS scheme: sample 06F report, analyte Salmonella species

Comments

Lab ID Method

Results

MC6838 Other

Not Detected

The sample contained Salmonella Bredeney at an approximate inoculum level of 10 CFU/g. The assigned value is therefore Salmonella species ‘detected’. This strain of Salmonella Bredeney is atypical of the genus on selective media and in confirmatory tests. It is H 2 S variable, lactose positive and shows poor growth in Simmons' citrate agar. The organism is typically motile and urease negative. It is a group B Salmonella according to the Kauffmann-White Scheme, with a full serological profile of ‘O’ antigen: 1, 4, 12, 27; ‘H’ phase 1 antigen: l, v and ‘H’ phase 2 antigen: 1, 7. Primary sources of Salmonellae are the gastrointestinal tract of animals; the organism can be transmitted via faeces into soil, water, feeds, foods and other animals, including humans.

MC6838 Broth 37/agar 37 (Various)

Not Detected

MC6954 Other

Detected

MC7139 PCR

Detected

MC7173 VIDAS

Detected

MC7213 Other

Detected

MC7233 PCR Detected MC7251 MKTT/RV + XLD + BGA 37 Detected MC7281 MKTT/RV + XLD + BGA 37 Detected MC7321 VIDAS Detected MC7415 MKTT/RV + XLD + BGA 37 Not Detected MC7458 Broth 37/agar 37 (Various) Detected MC7679 MKTT/RV + XLD + BGA 37 Detected MC7727 MKTT/RV + XLD + BGA 37 Detected MC7799 Other Detected MC7800 Other Detected MC7801 Other Detected MC7853 PCR Detected MC7926 Other Detected MC8152 MKTT/RV + XLD + BGA 37 Not Detected MC8174 VIDAS Detected MC8231 Other Detected MC9081 PCR Detected MC9208 PCR Detected MC9282 Chromogenic agar Not Detected MC9419 MKTT/RV + XLD + BGA 37 Detected MC9427 PCR Detected MC9474 Other Detected MC9502 PCR Detected MC9528 MKTT/RV + XLD + BGA 37 Not Detected

Methodology Summary

Method

% Satisfactory

77%

MKTT/RV + XLD + BGA 37

Broth 37/agar 37 (Various)

86%

VIDAS

94%

Rapid test (Various)

100%

Chromogenic agar

88%

PCR

100%

ELISA

100%

Other

90%

Data Statistics

Round

Detected

Assigned Value

Number of Results

154

Satisfactory

86%

When a round underperforms (<80% overall or <90% in specific cases), we verify sample integrity end-to-end: • Pre-dispatch QC (passed) – the batch met homogeneity and stability acceptance criteria prior to release with all 10 samples testing positive. • Retained-unit confirmation – batch records were rechecked and retained units re-tested; Salmonella was recovered from 100% of the 10 retained samples, confirming target content and viability. • Logistics assessment – we analyse time-to-receipt, transit distance and climate band for potential transport effects. No relationship was found. For lyophilised PT materials, organisms are effectively in suspended animation, so these variables are not typically associated with performance differences.

With stability and logistics excluded we continue to a full technical investigation, following a defined sequence.

1. Strain characterisation – each PT strain undergoes full culture analysis to understand behaviour across conditions: colony morphology on a range of agars, plus biochemical and serological profiling.

2. Method review – participant submissions are screened to identify any systematic differences between methods. In practice, pronounced method bias is rarely observed, as laboratories use validated Salmonella detection methods and performance is broadly comparable across methods.

CULTURE PROFILE – GROUP 6

LGC CODE

ORGANISM NAME

617 v2

Salmonella Bredeney

ORIGIN

SOURCE

Unknown

Wild strain

GROUP MORPHOLOGY

Enteric pathogens. Catalase positive and Oxidase negative. Salmonella - On Brilliant Green typical Salmonella growth Is pink colonies with pink agar. On MRSV Salmonella typically generates a central colony with a large pale halo of motility. On XLD Salmonella generates red colonies with black centres. Shigella sonnei - On SS agar produces no growth. On MC No.3 typical colonies are straw coloured. XLD typical growth is red colonies. COLONY MORPHOLOGY – GENERAL (from initial stocks) Incubation temp. and duration 24 hours @ 37 o C aerobic Blood Entire, slightly raised pale beige colonies ~2mm, α -haemolysis MacConkey Entire, flat pale pink colonies, irregular edges ~2mm, pale pink agar Nutrient Entire, flat shiny cream colonies ~2mm COLONY MORPHOLOGY - SALMONELLA Brilliant green Entire, flat pale green colonies, irregular edges ~2-3mm, green agar XLD Entire, slightly raised opaque yellow colonies ~1-2mm, yellow agar CASE 1-2mm entire shiny circular blue/green colonies BROTH GROWTH BU HQ +++ RV +++ BIOCHEMICAL TESTS Oxidase Negative Catalase Positive API 20 E profile 6704552 API 20 E identification Salmonella species 89.4% SEROLOGICAL TESTS

Method

% Satisfactory

77%

MKTT/RV + XLD + BGA 37 (various)

Broth 37 agar 37 (various)

86%

VIDAS

94%

Rapid test (various)

100%

Chromogenic agar

88%

PCR

100%

ELISA

100%

WKL scheme Serogroup

Positive

O:4 (B)

Salmonella latex

Other

90%

O antigens

1,4,12,27

H phase 1 antigens

I, v

H phase 2 antigens 1, 7

Prolab O antisera

Factor 4 Factor 12

Prolab phase 1 H antiosera

Prolab phase 2 H antiosera

Poly 1 complex +z6 7

3. Historical comparison – we examine prior PT rounds that used the same strain to detect recurring patterns. Where similar outcomes recur, this supports a strain- or matrix-linked effect; where prior performance was strong, the result is more likely round-specific. Subsequent rounds have gradually improved over time, suggesting participants have learned to recognise the characteristics of the strain.

MICROSCOPY

Motility

Motility observed

Gram stain

Short Gram negative rods in pairs and short chains GROWTH PROFILES

55°C (NA 48hrs) 44°C (NA 48hrs) 42°C (NA 48hrs) 37°C (NA 48hrs) Aerobic (NA 72 hrs)

30°C (NA 72hrs) 25°C (NA 3-5days) 22°C (NA 6 days) 6°C (NA 10 days) Anaerobic (NA 72 hrs)

+++ +++ +++

+++ +++ +++ +++

+++

GENERAL INFORMATION

Enumeration media Resuscitation media

NA SP/ PCA PP 24 hours @ 37 o C

Bead details Lot number

Sub x + 1 on 23/4/99

NA SP 24 hours @ 37 o C

Lactose positive and H 2 S variable Salmonella enterica subspecies enterica

Notes/Atypical reactions

All

Schemes suitable for

PROFILE APPROVAL

Date

7/8/25

Approved by

7/8/25

Progressive improvement in Salmonella Bredeney detection across PT rounds

Author: Andrew Cheetham Authorized by: Andrew Cheetham Year

Issue No.: 4 Issue date:6/8/25 Result

Round

Sample Contents

No. of results

Inoculum Level

% Correct

T:\Microbiology\Culture Collection\Culture Profiles\Group 6\617 S.Bredeney v2.docx

Page: 1 of 1

236

S. Bredeney

Positive

101

Dec-15

Jul-18

267

S. Bredeney

Positive

154

Sep-22

317

S. Bredeney

Positive

286

Sep-23

329

S. Bredeney

Positive

246

lgcstandards.com/AXIO

Insights from 30 years of Salmonella proficiency testing

Implications for participants

In this case, the same strain had been used in earlier PT rounds with similar outcomes, reinforcing that performance is best explained by the strain’s atypical phenotype (lactose-positive, H 2 S-negative) rather than method incompatibility. Targeted analyst training and closer adherence to Standard Operating Procedures (SOPs) should improve results.

Recommended actions:

• Use two selective or differential agars, where your SOP allows, to mitigate medium-specific inhibition. • Do not triage by appearance alone: at low-levels, confirm atypical colonies rather than discarding non-classic morphologies (e.g. lactose-positive, H 2 S- negative, small or pale). • Maintain strict pre-enrichment conditions (ratio, time, temperature); small deviations at low inoculum levels markedly reduce sensitivity. • Run parallel selective enrichments to avoid reliance on a single pathway; use dual enrichments where permitted. • Include a low-level positive control periodically to verify recovery under marginal conditions, and reinforce recognition of weak or atypical colony forms. • Review performance trends using PORTAL to confirm that SOP refinements deliver sustained gains.

Discussion

Our long-term dataset aligns closely with wider PT experience: laboratories perform strongly under routine conditions, but performance can decline when challenged with atypical phenotypes. This mirrors findings from major PT programmes in the US ( Edson et al .; Nemser et al.), where atypical colony morphology or biochemical behaviour is consistently associated with higher false-negative rates. For the S. Bredeney case study, correct detection increased from 83% in 2015 to 93% in 2023, indicating that repeated exposure improves recognition of atypical characteristics. Atypical strains pose specific interpretive challenges. Colonies that are lactose- positive, weakly H 2 S-negative or difficult to recognise on agar – for example small, pale or poorly developed colonies – can resemble background flora or fall outside analyst expectations. Such presentation issues remain a well-documented cause of false negatives across both our dataset and external PT studies . Together, these examples illustrate how biological variation interacts with analyst decision-making at the bench, and why performance tends to improve as laboratories become more familiar with these characteristics. A second, equally well-established driver of variability is inoculum level, particularly in matrices with low water activity, high fat content or intrinsic antimicrobial components . Very low inoculum levels often produce sublethally injured cells , making recovery highly sensitive to enrichment parameters, incubation conditions and analyst technique. PT experience consistently reflects these constraints, with low-level contamination samples generating more variable detection outcomes .

Not all unsatisfactory results, however, originate from biological complexity. A substantial proportion arise from routine process issues. Transcription errors, procedural drift (e.g. enrichment ratios, incubation times or temperatures) and occasional equipment problems were all highlighted by a recent AXIO survey and are well recognised across PT programmes . These represent correctable weaknesses that may not appear during routine QC, but become evident under PT challenge conditions. Although PT is sometimes criticised for not driving long-term improvement, later analyses show this often reflects staff turnover rather than limitations in PT design . Without mechanisms to retain learning between rounds, gains are often lost and performance can remain static. Taken together, these patterns emphasise the need for structured, end-to-end root-cause investigation supported by performance tracking over time. Trend review – particularly when viewed by matrix, strain and analyst within PORTAL – allows laboratories to distinguish isolated events from persistent issues, and to implement targeted actions including staff retraining, SOP refinement and instrument verification. PT therefore remains a central mechanism for benchmarking capability, developing analyst competency, and driving continuous improvement across a wide range of methods and matrices. Incorporating atypical strains and low-level challenges, as required under ISO 17043, ensures that PT exercises reflect the realities of foodborne-pathogen detection and support sustained strengthening of laboratory workflows.

AXIO Proficiency Testing – a trusted partner for microbiology testing

With over 40 years of experience, AXIO Proficiency Testing supports laboratory performance across food, water and environmental testing. The AXIO microbiology programme covers key quality control analytes, spanning routine pathogens and indicator organisms alongside less commonly assessed targets such as Shigella and psychrotrophic bacteria. Salmonella PT forms a core part of the portfolio, with well-characterised strains included across more than 30 food, feed and environmental matrices . These span commonly tested commodities as well as more challenging matrices, enabling laboratories to assess performance across different workflows and matrix types. easi - tab ™ complements PT through ISO 17034-certified quantitative microbiology tablets, including Salmonella -formats, supporting method verification, routine quality control and laboratory training. Visit lgcstandards.com/AXIO to get involved, or speak to one of our PT experts at axiopt@lgcstandards.com .

lgcstandards.com/AXIO

Authors

Tracey Noblett has worked as Head of Microbiology in the Proficiency Testing (PT) division at LGC for 19 years. She is responsible for the organisation of microbiology PT schemes and sample production, as well as developing new samples, providing technical support, and maintaining accreditation to ISO/IEC 17043. Tracey holds a 2:1 BSc in Microbiology from the University of Birmingham and has over 30 years’ experience in microbiological testing across clinical, water and food testing. She has been a member and secretariat of the Eurachem and/or EEE Proficiency Testing Working Groups since 2006. Dr Joe Lackey has worked as a Technical Manager at LGC Standards for eight years, collaborating with industry and academic partners to develop and apply reference standards across research and pharmaceutical workflows. His work spans drug discovery and pharmaceutical analysis, with further interests in microbiology and toxicology. He has authored 15 whitepapers and speaks regularly on these topics. Joe holds a PhD in Molecular Physiology from the University of Dundee, where he developed early drug-discovery approaches targeting growth-factor signalling in tumours.

This whitepaper was edited by Andy Blizzard , who joined LGC Standards as Content Writer in 2021. Andy previously studied for a BA in History from The University of Warwick and an MA in Public Communication from Westminster University. He is also an NCTJ-qualified journalist with more than 15 years’ experience of writing for print and online media.

lgcstandards.com/AXIO

Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12

Made with FlippingBook Online newsletter maker