Lab Matters Fall 2024 | Page 82

APHL 2024 POSTER ABSTRACTS

and quantification of these widespread viruses . Application of flexible techniques for elucidation of viral infectivity are essential for the effective monitoring of food and water supplies worldwide .

Presenter : Nathan Feirer , nathan . feirer @ promega . com

Emerging Insights on Postbiotics for the Prevention of Infectious Diseases

H . Hosseini , K . Hsieh , San Mateo Public Health Lab

Introduction : Ensuring the safety of food is essential to promoting overall health by preventing infectious diseases and providing essential nutrients . Postbiotics are included inactivated microbial cells ( dead cells ), cell fractions ( peptidoglycan-derived muropeptides , teichoic acids , endo- and exo-polysaccharides and cell surface proteins ), or cell metabolites ( short-chain fatty acids ( SCFAs ), enzymes , bacteriocins and organic acids ) that are made by live probiotic cells through the fermentation process , in response to gut conditions and / or released after lysis ( when exposed to physical and / or chemical cell inactivation conditions ) and confer various physiological health benefits to the host when administered in adequate amounts .

Method : A comprehensive review of English research articles published within the last 10 years was conducted using relevant terms in databases such as PubMed , Cochrane Library , Web of Science and CINAHL .

Discussion : Postbiotics can emulate the fundamental and clinical roles of probiotics which are living organisms . The capability of postbiotics to maintain the host ’ s health against serious infections induced by pathogens is fulfilled through various mechanisms such as suppression and elimination of foodborne pathogen colonies and biofilms , inhibition of pathogenic adhesion , invasion , biofilm formation and improvement of immune responses in the gut and promote the host ’ s immune system by activation innate immunity and stimulate secretion of IL-12 , at the meantime they exert antibacterial and anti-viral activities through reducing the invasion of pathogens and producing INF . In addition , specific chemical structure of some postbiotics derived from L . rhamnosus HN001 leads to an increase in the phagocytic activity of leucocytes , which in turn improves immune system function . Food is one of the most important ways of entering infectious pathogens to body , so presence of adequate postbiotics such as nisin in food can prevent foodborne infectious diseases reasonably . The effectiveness of postbiotics in food matrices depends on factors such as the parent probiotic strains from which the postbiotics are derived , the type of target pathogen microorganism , concentration and form of application ( liquid / powder ) and the features of the food matrix .

Conclusion : The prevention of infectious diseases through the utilization of postbiotics in food relies on non-living microbiome components . Postbiotics mediate their effects through active antimicrobial properties , metabolites and signaling molecules , which exhibit antiinflammatory and immunomodulatory properties . Additionally , they eliminate or reduce the growth of infectious microorganisms in food and the gut due to their antioxidative and antimicrobial activities .

Presenter : Hedayat Hosseini , hedayat . s . hosseini @ gmail . com

Enhancing Food Safety Laboratories : Best Practices from an APHL Fellowship Experience

O . Ijabadeniyi , Maryland Department of Health Laboratories Administration

This poster highlights key insights gained through an APHL fellowship at a US public health laboratory , focusing on best laboratory practices crucial for ensuring the generation of reliable food safety test results . Observations underscore the importance of placing a continuous emphasis on laboratory ethics and upholding data integrity as well as maintaining a robust Quality Management System ( QMS ) including quality control such as gram stain QC , media QC , pathogen environmental monitoring and fridge / freezer temperature monitoring .

These identified practices hold significant potential for enhancing the quality and credibility of food safety laboratories , particularly beneficial for those within academic institutions that may not undergo ISO / IEC 17025 audits . The recommendation is to integrate these practices to fortify the foundations of food safety laboratories , ensuring alignment with international quality standards and fostering a culture of excellence .

Acknowledging the practical constraints of auditing academic laboratories to ISO / IEC 17025 , the proposal suggests developing a tailored QMS standard for academic institutions . This tailored standard aims to guide compliance , thereby raising the overall standards of laboratories within academic settings .

Additionally , reflections from the APHL training underscore the importance of effective time management , prioritization and maintaining professional integrity for lab scientists managing substantial workloads . These reflections serve as valuable lessons for navigating the challenges of a demanding work environment , contributing to the continual improvement of laboratory practices and fostering professional growth .

Presenter : Oluwatosin Ijabadeniyi , tosynolu @ yahoo . com

Fifteen Years of CaliciNet : Norovirus Genotype in the United States , 2009-2024

L . Barclay , A . Montmayeur , J . Vinjé , Centers for Disease Control and Prevention

Background : Noroviruses are the leading cause of epidemic and endemic acute gastroenteritis ( AGE ) in the US . CaliciNet , launched in 2009 , is a national laboratory norovirus surveillance network of local and state public health and food regulatory agency laboratories coordinated by CDC to identify , genotype and compare norovirus sequences using standardized protocols . In 2024 , the network consisted of 37 laboratories across 30 states and DC . Since 2010 , five CaliciNet-Outbreak Support Centers perform norovirus outbreak typing from the remaining 20 states that do not participate in CaliciNet ; in 2019 , sequences from sporadic samples could be uploaded .

Methods : Epidemiologic and genotypic data from AGE outbreaks from September 1 , 2009 — December 31 , 2023 and from sporadic cases since 2019 , were downloaded from CaliciNet and analyzed in MS Excel . Next-generation sequencing data uploaded to CaliciNet were downloaded and analyzed using MEGA .