APHL 2023 POSTER ABSTRACTS from locations near the genitals had the highest positivity rate (~ 41 %), followed by hands (~ 38 %), face (~ 33 %), mouth (~ 32 %), chest / abdomen (~ 23 %), and feet (~ 20 %). Specimens from all other sources , including those that were unspecified , had a positivity rate of ~ 24 %. When 2 or more lesions from the same individual were tested , 97 % of individuals had consistent results for all collections , either detecting ( 33 %) or not detecting ( 67 %) NVO DNA . Discrepant results with multiple collections , some having NVO DNA and others not having NVO DNA were seen in 3 % of individuals . These individuals were considered to be positive for mpox virus . From May through December of 2022 , the NCSLPH tested 841 dry swab specimens derived from 450 patients to detect NVO DNA in 142 individuals ( 32 % positivity rate ). Forty-two duplicate specimens derived from infected individuals were sent to the CDC for further characterization and all 42 were confirmed to be the West African clade ( Clade II ) of mpox virus . Overall , specimens collected from locations near the genitals were more likely to be NVO positive , while specimens from the feet were least likely to be positive . These data suggest that collection from near genital sites would increase the likelihood of mpox virus detection . In addition , our data supports that collection from two anatomical sites , with one being located near the genitals would have detected all cases that were submitted for testing .
Presenter : Brandon Skinner , brandon . skinner @ dhhs . nc . gov
Machine Learning-based Typing of Staphylococcus species by the Fourier-Transform Infrared ( FT-IR ) Spectroscopy with IR Biotyper for Clinical Surveillance
T . Stephens , B . Adams , H . Naikare ; Tifton Veterinary Diagnostic & Investigational Laboratory
Staphylococci are a group of microorganisms occurring widely in nature and commonly found on the skin , mouth , nose , and gastrointestinal tract of dogs . The Staphylococcus genus includes over 30 species correlated with both animal and human pathogens . Typing of these bacterial pathogens in clinical hospitals relies on traditional methods that are expensive , time-consuming , and often limited to referral laboratories . IR Biotyper ( Bruker Daltonik , Germany ) is a new alternative physico-chemical method based on measurement of vibration of a molecule excited by IR radiation at a specific wavelength range . The IR Biotyper utilizes FTIR spectroscopy to discriminate bacterial isolates at different taxonomic levels ( genus , species , serogroup / type , and strain level ) by analyzing their total composition ( proteins , fatty acids , carbohydrates , nucleic acids and lipopolysaccharides ) on the cellular surface of the microbial cells . In this study , we evaluated the ability of the FTIR spectroscopy to discriminate amongst Staphylococci isolates derived from canine skin samples . With the IR Biotyper , strain typing and data analyses could be accomplished in less than three hours , The use of this technique by clinical microbiology laboratories could help to assist in rapid source tracking , clinical surveillance and microbial surveillance tracking .
Presenter : Taylor Stephens , taylorstep098 @ gmail . com
Maximizing Efficiency in Arboviral Mosquito Surveillance Through Multiplex Polymerase Chain Reaction and Sample Pooling
D . Bolton , R . Lovell ; New Hampshire Public Health Laboratories
Introduction : Jamestown Canyon virus ( JCV ) is spread to people through the bite of an infected mosquito , and is an emerging disease in New Hampshire ( NH ). Nineteen human cases have been detected in NH since 2013 . The New Hampshire Public Health Laboratories ( NH PHL ) recognized the importance of adding JCV to the existing mosquito surveillance program , but needed to work within the constraints of limited funding for reagents and personnel . One of the biggest challenges presented by the COVID-19 pandemic has been allocating resources for testing other than SARS-CoV-2 . Historically , the mosquito surveillance program in NH included testing mosquito batches for Eastern Equine Encephalitis virus ( EEE ) and West Nile virus ( WNV ) by duplex PCR . The NH PHL sought to optimize a multiplex PCR to include all three targets : EEE , JCV , and WNV . Additionally , a pooling strategy was utilized to maximize efficiency in testing for the extraction and PCR steps of the process . Method ( s ): The NH PHL performs real-time reverse transcriptase polymerase chain reaction ( rRT-PCR ) for mosquito surveillance using the CDC developed TaqMan method . Mosquito batches are processed using a Retsch Mixer Mill ; nucleic acid is extracted using the KingFisher Flex instrument ; and PCR testing is performed using the QuantaBio qScript™ XLT One-Step RT-qPCR ToughMix ®, Low ROX™ enzyme kit on the ABI 7500 Fast ( or Fast DX ) instruments . PCR primer / probe concentrations were optimized for the three targets in the multiplex . Next , verification testing was performed to determine accuracy and precision , using a panel of RNA samples . Once the verification work was complete , the NH PHL established a pooling strategy that allowed for an increase in testing capacity from 93 mosquito batches to 372 batches per PCR plate . Results : The NH PHL ’ s verification demonstrated 100 % accuracy for the multiplex PCR . Accuracy was determined by whether the expected results ( detected or not detected ) were obtained with all targets . Evaluation of precision data showed the average absolute difference in cycle threshold ( Ct ) values for each target was less than one when comparing the multiplex with previous methods . Pooling did not significantly affect sensitivity in detecting EEE , JCV , and WNV . Discussion : Verification of a multiplex PCR and pooling maximized efficiency and enabled the NH PHL to enhance mosquito surveillance with limited resources . The results of this work helped to establish routine testing for JCV without significant additional cost or time .
Presenter : Rebecca Lovell , rebecca . a . lovell @ dhhs . nh . gov
Method Optimization and Validation of Per- and Polyfluoroalkyl Substances in Human Serum Using On-line Solid Phase Extraction Ultra Pressure Liquid Chromatograph Tandem Mass Spectroscopy
Z . Li , C . Xu , D . Mathes , C . Lestician , A . Lin , S . O ’ Leary , T . Fan , L . Zhong ; New Jersey Department of Health Public Health and Environmental Laboratories
Per- and polyfluoroalkyl Substances ( PFAS ) are a large group of manufactured chemicals that are persistent and potentially hazardous . PFAS is tested in human serum with high performance liquid chromatography tandem mass spectrometry ( HPLC-MS / MS ), typically after solid phase extraction ( SPE ). Although it can
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