Lab Matters Fall 2024 | Page 40

APHL 2024 POSTER ABSTRACTS

AGRICULTURAL , VETERINARY AND ENVIRONMENTAL TESTING TECHNOLOGIES AND PRACTICES

Automated Workflow for High-Throughput PFAS Sample Preparation for Solid Matrices Following EPA Method 1633

E . Walters , Biotage

Per- and polyfluoroalkyl substances ( PFAS ) are toxic compounds known for their persistence , potential health risks and their ability to accumulate in living organisms , including humans . As the concern about PFAS contamination grows , analytical methods become paramount in accurately detecting and quantifying these substances across different sample types . This work focuses on an automated workflow for the extraction of PFAS in solid samples . The study evaluates the extraction performance using US Environmental Protection Agency ( EPA ) Method 1633 criteria for method detection limits ( MDLs ), precision and accuracy for the determination of 40 target PFAS analytes . Sample homogenization , liquid extraction , solid phase extraction , solvent evaporation and concentration is performed in an efficient workflow utilizing the Biotage Lysera , TurboVap LV and Extrahera HV-5000 . Results demonstrate measured detection limits , precision and accuracy exceeding EPA method 1633 acceptance criteria for initial demonstration of capability . In addition , this work outlines a simple sample preparation technique that enables high throughput processing of samples while maintaining exceptional data quality . Advantages of this workflow include elimination of manual transfer steps , complete preparation of up to 24 samples in less than four hours and minimal cleaning required between sample batches . In conclusion , this automated workflow offers a highly efficient and reliable solution for PFAS analysis in non-drinking water samples , addressing key challenges and surpassing EPA Method 1633 performance criteria .

Presenter : Evan Walters , evan . walters @ biotage . com

Canine Tickborne Diseases in Montana - A Serology Study Using Indirect Fluorescence Antibody ( IFA ) Assays

G . Glover , S . Horak , B . Eilers , E . Schwarz-Collins , Montana Veterinary Diagnostic Laboratory

Changing climatological factors have resulted in the expansion of tickborne diseases throughout regions previously thought to be free of certain arachnid vectors and their associated infectious agents . Humans and dogs can be affected by many of the same tickborne infectious agents and can experience similar clinical symptoms and disease processes . Some tickborne diseases that are common to dogs and humans are Lyme disease ( Borrelia burgdorferi ), anaplasmosis ( Anaplasma phagocytophilum ), ehrlichiosis ( e . g ., E . chaffeensis , E . ewingii and E . muris ) and Rocky Mountain spotted fever ( Rickettsia rickettsii ). Transmission of these tickborne diseases to humans typically occurs in the upper Midwest , Northeastern and Southeastern parts of the US , especially during intense warm weather months ( June-August ). In Montana , the prevalence of endemic tickborne disease in both humans and dogs is thought to be virtually nonexistent , but there have been no studies to date that estimate seroprevalence in either dogs or humans . Up to 51 % of the human population in Montana owns one or more dogs in their home . With a population of approximately one million people living in the state and twice as many canids , dogs may serve as a potential sentinel species for understanding the risk of tickborne disease to people . In order to estimate whether tickborne diseases of public health importance are present in Montana , this study will utilize indirect fluorescence antibody ( IFA ) titer tests to determine whether canine serum samples submitted to the Montana Veterinary Diagnostic Laboratory have evidence of antibodies to the aforementioned four tickborne diseases ( B . burgdorferi , A . phagocytophilum , E . canis and R . rickettsii ). Results of this study will be used to help understand whether tickborne disease is present in the state , thus guiding medical and veterinary practitioners as well as animal health and public health officials in clinical , diagnostic and policy decision making .

Presenter : Geneka Glover , glover . geneka @ yahoo . com

Characterization of SARS-CoV-2 Lineages from Indoor Air Samples

H . Barbian 1 , S . Bobrovska 1 , D . Yuce 2 , S . Green 1 , V . McSorley 2 , A . Kittner 2 , M . Pacilli 2 , Rush University Medical Center 1 , Chicago Department of Public Health 2

Background : The SARS-CoV-2 pandemic has underscored the need for early detection and ongoing surveillance of viral pathogens . As individual testing behaviors change , environmental surveillance may be key to timely public health responses for newly emerging pathogens and infections that are largely unreported . Wastewater surveillance has been valuable for tracking SARS-CoV-2 levels and variants at population-level . Indoor air surveillance is emerging as a potential complement to existing wastewater and syndromic surveillance for pathogen detection and lineage characterization at both the room / institution-level and for citywide surveillance . However , it remains largely untested , especially in high-risk / outbreak settings . To address this need , the Chicago Department of Public Health ( CDPH ), in collaboration with the Regional Innovative Public Health Laboratory ( RIPHL ), a public health / academic partnership between CDPH and Rush University Medical Center for advanced molecular detection , deployed air samplers in healthcare and congregate settings throughout Chicago . This surveillance effort began in February 2023 and was conducted to assess the feasibility of monitoring locations of public health importance using air sampling to detect the genetic material of pathogens circulating in the air .

Methods : Indoor air samplers ( n = 10 ) were deployed by CDPH at three acute care hospitals , two skilled nursing facilities , a longterm acute care hospital , a specialty clinic , a transitional housing facility and a correctional facility . The placements represented three of the six Healthy Chicago Equity Zones . Air samples were collected via continuous sampling for one week using Thermo Fisher AerosolSense™ samplers and transported to RIPHL . Total nucleic acids ( TNA ) were extracted from weekly air samples and SARS-CoV-2 presence was assessed using quantitative PCR ( qPCR ). In addition , whole genome sequencing of SARS-CoV-2 viruses was performed on TNA extracts using a multiplexed amplicon library preparation protocol commonly used for clinical specimens . Percent reference coverage and relative SARS-CoV-2 lineage abundances were determined using Freyja .

Results : Air samples from 11 collection weeks and 10 sites were