APHL 2022 POSTER ABSTRACTS
Infectious Diseases
Presenter : Roxana Cintron-Moret , Centers for Disease Control and Prevention , vrw7 @ cdc . gov
Evaluation of Etest , Liofilchem and Neo-Sensitabs for Phenotypic Detection of Metallo-β-lactamases
S LaVoie 1 , P Bumpus-White 2 , A Bhatnagar 1 , A Brown 1 , M Karlsson 1 ;
1
Centers for Disease Control and Prevention , 2 Goldbelt C 6 , LLC
Background : Carbapenemase-producing organisms are an urgent public health threat . They limit antibiotic treatment options and can spread rapidly in healthcare settings . The rise of metallo-βlactamase ( MBL ) type carbapenemases are of particular concern since these enzymes confer resistance to almost all β-lactam antibiotics . Early detection of MBLs is critical for effective patient management , including infection prevention ( IP ) and treatment . Molecular detection requires either PCR , using a validated assay that can detect the targeted genes , or whole genome sequencing ( WGS ), which costs additional time and money . Our goal was to identify a phenotypic MBL screening test to enhance detection of MBL enzyme production through routine testing , thereby alerting for rapid IP responses .
Methods : We compared performance of three commercial phenotypic screening tests for MBL detection : the Rosco Neo- Sensitabs combined disk test ( imipenem / imipenem + EDTA ) and two agar gradient diffusion tests ( bioMérieux MBL Etest and Liofichem MBL MIC Test System ( MTS )). Gradient tests included both the high-range imipenem / imipenem + EDTA ( IP / IPI ) and lowrange meropenem / meropenem + EDTA ( MP / MPI ) strips . Sixty well-characterized carbapenemase-producing Acinetobacter ( n = 9 ), Enterobacterales ( n = 34 ) and Pseudomonas ( n = 17 ) isolates were selected for this study ; thirty produced an NDM- , VIM- , IMP- , SIM- , or SPM-type MBL . Testing was performed in accordance with the manufacturer ’ s instructions and repeated when results were discordant with WGS .
Results : The accuracy of Neo-Sensitabs , IP / IPI Etest and IP / IPI Liofilchem was 90 %, 82 % and 67 %, respectively . Adding low-range MP / MPI strips increased overall accuracy to 90 % for Etest and 73 % for Liofilchem . The lower accuracy for Liofilchem was due to 27 % off-scale indeterminate results . Sensitivity and specificity for the Neo-Sensitabs were 83 % and 97 %, respectively , with five falsenegatives ( 3 IMP , 1 NDM and 1 VIM ) and one false-positive ( OXA- 66 / 72 ) observed . Both sensitivity and specificity were 90 % for Etest and 83 % and 63 %, respectively , for Liofilchem . One IMP isolate gave a false-negative for both Etest and Liofilchem and one false-positive OXA-66 / 72 was observed for Etest .
Conclusions : The combination of IP / IPI and MP / MPI MBL Etest had the best sensitivity and specificity for detecting MBL carbapenemase production in this study . Although Neo-Sensitabs are less expensive than Etest , their lower sensitivity makes them less ideal for MBL detection . Phenotypic screening can enhance MBL detection , particularly for novel carbapenemase genes not targeted by routine PCR testing , without having to wait for WGS information . Early detection of MBLs through screening can inform infection control to help prevent their spread to other patients .
Presenter : Stephen LaVoie , Centers for Disease Control and Prevention , qea5 @ cdc . gov
Integrating Epidemiological and Laboratory Data into Informative Visualizations with MicrobeTrace
A Shankar , R Kelly , R Clinton-Moret , E Moscoso and W Switzer , Centers for Disease Control and Prevention
Challenge addressed : Laboratory data aids outbreak investigations , but few tools integrate laboratory and epidemiological data and fewer can be used on novel organisms ( e . g ., SARS-CoV-2 ) or can explore relationships with other data types . Many tools require specialized bioinformatics or coding skills , which hinders use . We describe MicrobeTrace , a pathogen-agnostic data integration and visualization tool , for outbreak investigations and response for emerging pathogens and a special-purpose version of MicrobeTrace for hantavirus classification and outbreak studies .
Methods : Although MicrobeTrace was originally developed for analysis of HIV data , the MicrobeTrace team rapidly responded to changing priorities and adapted the tool for other pathogens , including SARS-CoV-2 . We developed specific training documents and provided ad-hoc training for epidemiologists to use during active investigations . The team also developed bioinformatic methods for exporting phylogenetic trees and viral genetic distance matrices from the widely used viral tracking tool NextStrain and using the output for rich visualization in MicrobeTrace . We also developed a special-purpose MicrobeTrace version , HantaNet , to classify hantaviruses based on a set of reference sequences and to assist with outbreak investigations .
Results : Public health partners have adapted MicrobeTrace by itself or in combination with Nextstrain for analysis of SARS-CoV-2 and COVID-19 data . MicrobeTrace has provided public health support and guidance to state and local health labs working with various pathogens , including SARS-CoV-2 , HIV , TB and hantaviruses , helping them generate data visualization to inform targeted response and policy .
Conclusions and impact on public health : MicrobeTrace provides an intuitive , flexible and powerful tool with broad applicability . This tool can be used to integrate and visualize laboratory , epidemiological and / or contact-tracing data to understand disease transmission networks and dynamics .
Presenter : Anupama Shankar , Centers for Disease Control and Prevention , ikb6 @ cdc . gov
Laboratory Surveillance for Disseminated Gonococcal Infection - A Critical Role of SURRG-Center of Excellence Laboratories to Support Statewide Neisseria gonorrhoeae Antimicrobial Susceptibility Testing
S Budiono 1 , J Weiner 1 , M Khubbar 1 , Z Netterfield-Amezquita 1 , T Guzman 1 , N Balakrishnan 1 , H Hermus 1 , J Dalby 2 , D Shrestha 3 , J Pfister 3 , B Kufalk 3 , L Amsterdam 3 , S Bhattacharyya 1 ; 1 City of Milwaukee Health Department , 2 University of Wisconsin – Madison ,
3
Wisconsin Division of Public Health
Introduction : As one of eight SURRG project sites ( Strengthening the US Response to Resistant Gonorrhea ), the Milwaukee Health Department Laboratory ( MHDL ) has been performing GC-AST using the Etest method since 2017 . MHDL also participates in CDC ’ s Gonococcal Isolate Surveillance Project ( GISP ) for urethral GC- AST surveillance . In the second five-year funding cycle , expansion of Antibiotic-Resistant Gonorrhea ( ARGC ) surveillance in higher