Lab Matters Fall 2023 | Page 62

APHL 2023 POSTER ABSTRACTS

quantity of DNA extracted . Methods : For CLIA-regulated tests , DNA was extracted from 12 Streptococcus pneumoniae isolates and plated alternating with 12 no template control ( NTC ) wells to test for sample carryover . For nonregulated tests , we extracted DNA from 3-5 isolates of seven organisms ( Salmonella enterica , Shiga toxinproducing Escherichia coli , Enterobacter cloacae , Acinetobacter baumannii , Klebsiella species , Pseudomonas species , and Escherichia coli ) and 1 negative control ( NTC ) per run . Extracted DNA quantity was assessed using a Qubit spectrophotometer . DNA quality was assessed with a Nanodrop 2000 spectrophotometer by measuring absorption peaks at 260 and 280 nanometers and calculating peak ratios ; a ratio of 1.8 was considered pure DNA and ratios of 1.7 – 2.2 were considered acceptable . We sequenced DNA extracted from ≥1 isolate per organisms using the MP24 and compared resulting quality metrics to those of DNA sequences from the same organisms extracted by the MagNA Pure LC 2.0 . Results : DNA quantity was similar to DNA obtained with the MagNA Pure LC 2.0 ( mean 14.78 ng / ul Salmonella extracted with MagNA Pure LC 2.0 vs 20.66 ng / ul with MP24 ). DNA from all organisms extracted by the MP24 had sufficient quality for use in sequencing and all 260 over 280 ratios were within 1.7 – 2.2 . Sample carryover did not occur . DNA recovered from negative controls run with S . pneumoniae isolates was too low to detect . All assessed sequencing quality metrics indicated MP24-extracted DNA was suitable for use in downstream sequencing , including CLIA-regulated tests . Conclusion : This study validates MP24 use as a replacement for the MagNA Pure 2.0 instrument . Our validation plan and data might be useful for other public health laboratories to validate DNA extraction instruments used for CLIA-regulated and nonregulated sequencing analysis .

Presenter : Matthew Martin , tqe7 @ cdc . gov

Validation of the Roche COBAS ® 5800 for Detection of Hepatitis C Virus ( HCV )

N . Braun 1 , K . Margulieux 2 , B . Robeson 1 , D . Riner 1 ; 1 Michigan Department of Health and Human Services , 2 US Centers for Disease Control and Prevention

Background : The Michigan Department of Health and Human Services ( MDHHS ), Bureau of Laboratories ( BOL ) experienced a 30 % increase in specimens submitted for hepatitis C virus ( HCV ) antibody and nucleic acid testing in 2022 . BOL evaluated the Roche COBAS ® 5800 System , a compact molecular testing platform with increased testing volume capacity that performs an automated nucleic acid amplification test to detect and quantify HCV . Performance and workflow for the COBAS ® 5800 System were compared with the COBAS ® Ampliprep / COBAS ® TaqMan ® HCV Test currently in use at BOL . Methods : Roche provided an HCV validation panel . A linearity assessment was performed using 24 positive HCV samples with an expected analyte concentration range of 55 – 3 × 10 7 IU / ml . Precision and accuracy were determined by testing a total of 15 low ( 1000 IU / ml ) and 15 high ( 1 × 10 6 IU / ml ) analyte concentration samples over five days . The assay ’ s limit of detection ( LOD ) was tested using 20 low analyte concentration replicates . A method correlation study compared performance of the COBAS ® 5800 System HCV Test with the COBAS ® Ampliprep / COBAS ® TaqMan ® HCV Test using 44 deidentified clinical samples previously tested for HCV . Analyte specificity was determined by testing 22 serum samples antibody reactive for Treponema pallidum , HIV , hepatitis A virus , or hepatitis B virus . Workflow analysis measured average time per run and maintenance for both platforms . Results : Linear range for HCV samples tested on the COBAS ® 5800 System was successfully established with an R2 value of 0.99 . For precision , all sample results fell within two standard deviations from established means . Precision inter-run coefficient of variability (% CV ) for low and high concentration sample results were calculated at 6.17 and 4.72 , respectively . Accuracy was determined and all sample results fell within expected intra-assay variation of +/ - 0.5log10 . HCV was detected in all 20 LOD panel samples with an observed range of < 15 to 215 IU / ml . Platform comparison results using 38 HCV-positive and 6 HCV-negative samples had 100 % agreement . Linear regression analysis of platform comparison results returned an R2 value of 0.98 . Analyte specificity was 100 % in 21 / 22 samples with no HCV detected ; one sample returned an “ HCV Invalid ” result caused by sample aspiration error . Workflow analysis showed the COBAS ® 5800 System provided appreciable time savings at all stages of sample processing and maintenance , compared with the COBAS ® Ampliprep / COBAS ® TaqMan ® HCV Test . Conclusion : The COBAS ® 5800 System is an acceptable testing platform for HCV detection in clinical samples . Implementation of the COBAS ® 5800 System for HCV testing will increase laboratory testing capacity , reduce time required for hands-on sample manipulation , and decrease turnaround time to reportable results .

Presenter : Katie Margulieux , tqe6 @ cdc . gov

DIVERSITY , EQUITY AND INCLUSION

Creating an Inclusive Workplace : Initiating and Implementing a Diversity , Equity and Inclusion Work Group in a Public Health Lab

J . Laine , Minnesota Department of Health

Diversity , equity and inclusion is vital to all public health laboratories as we collectively work to entice a more diverse candidate pool , increase retention of current and future employees , and make our workplace more inclusive and welcoming . The Minnesota Public Health Laboratory ( MN PHL ) established a Diversity , Equity , and Inclusion ( DEI ) work group in April 2021 , with members representing each area of the PHL ; Environmental , Infectious Disease , and Newborn Screening . The goal of the MN PHL DEI work group is to embed Diversity , Equity , and Inclusion practices , principles , and language into everyday work . This poster will share how to implement a DEI work group , built from the ground up to include staff from all levels of the Public Health Laboratory . Items such as creating a charter , establishing goals , planning tools utilized in creating a work group , and defining a vision for the work group will be discussed . We will share initiatives completed in our first year , addressing recruitment and leadership initiatives . Summary questions and results of a division wide survey of employees and their perceptions of DEI in their workplace will be represented . In general , results of the survey indicated that while most respondents felt welcome in the workplace , there was a need for further education regarding definitions of DEI and what embedding DEI in their workplace meant for them as employees of a public health laboratory . Survey respondents felt that they wanted to feel more comfortable discussing DEI initiatives by learning more about these topics and working to ensure a welcoming , open work environment in which to have those conversations . Current work initiatives