APHL 2019 POSTER ABSTRACTS
Foodborne Botulism in Home Canned Vegetables: An
Evaluation of Botulinum Neurotoxin and Clostridium
botulinum Detection Methods
Partnership for Food Protection’s Human and Animal Food
Testing Laboratories Best Practices Manual
C-A. Da Costa-Carter , M. Perry , B. Zhao , A. Chiefari , M. D’Amico ,
M. Conlon 2 , D. Centurioni 2 , S. Hughes 1 , C. Egan 2 , J. Rakeman 1 ; 1 New
York City Public Health Laboratory, 2 New York State Department of
Health - Wadsworth Center
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In the summer of 2018, New York City Public Health Laboratory
(PHL) and New York State Wadsworth Center Laboratory (WC)
participated in a foodborne botulism investigation that involved 3
adult family members and home canned vegetables. To establish
a link between the clinical cases and a suspect food source it was
necessary to use several assays to identify botulinum neurotoxin
(BoNT) activity and the presence of culturable Clostridium
botulinum.
All three adults exhibited botulism symptoms and were treated with
botulism anti-toxin. Split specimens from the three patients were
sent to both PHL and WC for concurrent testing and included two
serum specimens collected before anti-toxin administration from
each of two patients and three stool specimens collected after
anti-toxin administration from each of the three patients. BoNT A
activity was detected in patient serum collected before treatment
and not in stool specimens collected after treatment with anti-
toxin. However, C. botulinum toxin A and B gene DNA was detected
in stool specimens from all three patients. Among all of the food
products initially tested, only residue from the salad bowl from
which the patients ate tested positive for C. botulinum toxin gene
DNA and BoNT A activity. The original food source of BoNT at the
patient home was eventually found in a relatively clean and empty
jar that was presumed to have contained peas used in the salad.
Eluate from the empty pea jar was used to detect BoNT A activity
and to culture C. botulinum. Clinical isolates were obtained from
two of the patients and using NGS SNP analysis these isolates were
definitively linked to isolates from the pea jar eluate. Results from
this investigation illustrate the utility of employing a variety of assays
to link patient cases of BoNT poisoning with a food source.
Presenter: Cherry-Ann Da Costa-Carter, New York City Public Health
Laboratory, New York, NY, [email protected]
Led by the FDA, the Partnership for Food Protection (PFP) is a
multi-agency organization dedicated to establishing a strong
and effective integrated food safety system in the United States.
PFP’s work is allocated across several workgroups, comprised of
strategic partners in federal, state, and local government charged
with advancing the PFP’s mission in a coordinated and efficient
manner. The PFP’s Laboratory Science Workgroup was charged with
documenting best practices for human and animal food laboratories
to build confidence among stakeholders in the integrity and
scientific validity of laboratory analytical data and to facilitate the
acceptance of laboratory analytical data by regulatory agencies.
The Human and Animal Food Testing Laboratories Best Practices
Manual is a consensus document, and the FDA Office of Regulatory
Affairs (ORA) has adopted the earlier revision of this document
(2013) as a crucial operational resource. The manual’s degree of
acceptance and integration in ORA laboratory work supports its
intended purpose to promote data sharing among federal, state,
local, territorial, and tribal human and animal food regulatory
agencies.
Documenting the quality of both sampling and analysis is essential
to ensure the defensibility of laboratory generated data. For that
reason, many agencies have been reluctant to accept and act
on data other than their own. To facilitate data acceptance, the
PFP Laboratory Science Workgroup identified essential elements
critical to the quality of regulatory data. The Human and Animal
Food Testing Laboratories Best Practices Manual provides a set
of tools, definitions, and references that laboratories can use to
improve their operations. The workgroup strongly recommends
that laboratories wishing to exchange data with regulatory partners
adopt these best practices.
As governmental regulatory partners increasingly embrace
prevention-based approaches to food safety, including widespread
surveillance efforts, the demand for laboratories that meet
recognized best practices of analytical competency will rise
dramatically. These best practices enable regulatory agencies to
more expeditiously utilize laboratory data to identify, prevent, and
remove unsafe food products from the marketplace. Considering
the rapid globalization of the U.S. food market, and the growing
pressure to ensure that imported food is safe for consumption, it
has never been more important for these agencies to leverage the
resources of the nation’s food laboratories and join forces to take a
prevention-based approach to food safety.
Presenter: Maria Ishida, New York State Department of Agriculture
& Markets, Albany, [email protected]
Evaluation and Feasibility of Two Modified Commercial PCR
Kits to Screen CIDT Stools for Shiga Toxins
K. Starr 1 , R. Gee 2 , G. Olson 2 , W. Glover 2 ; 1 University of Washington
Medical Center, 2 Washington State Public Health Laboratories
Background: Shiga toxin-producing Escherichia coli (STEC) are food-
borne pathogens of clinical and public health importance. Shiga
toxins (Stx1 and/or Stx2) have a prominent role in the pathogenesis
of STEC bacteria. The introduction of culture-independent diagnostic
54
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The mouse bioassay (MBA) is considered the gold standard assay
to identify BoNT activity, but it is a labor intensive assay, results can
take up to 2-5 days to report, requires large sample volume, can
result in non-specific test results, and its use does not establish a
definitive link between patient cases and the environmental source
of BoNT. As a result of the limitations associated with the MBA,
matrix-assisted laser desorption/ionization time-of-flight mass
spectrometry (MALDI-TOF MS) was also used to rapidly detect and
characterize BoNT activity. Furthermore, to identify and characterize
C. botulinum present in clinical specimens and food samples,
multiplex PCR was used for detection of C. botulinum toxin gene
DNA and next generation sequencing (NGS) single nucleotide
polymorphism (SNP) analysis was used to type C. botulinum isolates
cultured during the investigation. Because of the different assays
utilized, this investigation provides a unique opportunity to assess
and compare C. botulinum and BoNT detection methods in clinical
specimens and food samples.
C. Mangione 1 , Robyn Randolph 1 ; 1 New York State Department of
Agriculture & Markets, 2 Association of Public Health Laboratories