Lab Matters Summer 2019 - Page 56

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 1 2 1 2 2 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, hcdacosta@health.nyc.gov 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, maria.ishida@agriculture.ny.gov 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 LAB MATTERS Summer 2019 PublicHealthLabs @APHL APHL.org 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