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Truswell, A.

Publications and source records attributed to Truswell, A..

2 recordsLinked to original sources

Robotic Antimicrobial Susceptibility Platform (RASP): A Next Generation Approach to One-Health Surveillance of Antimicrobial Resistance.

BackgroundSurveillance of antimicrobial resistance (AMR) is critical to reducing its wide-reaching impact. Its reliance on sample size invites solutions to longstanding constraints regarding scalability. A robotic platform (RASP) was developed for high-throughput AMR surveillance in accordance with internationally recognised standards (CLSI and ISO 20776-1:2019) and validated through a series of experiments. MethodsExperiment A compared RASPs ability to achieve consistent MICs to that of a human technician across eight replicates for four E. coli isolates. Experiment B assessed RASPs agreement with human performed MICs across 91 E. coli isolates with a diverse range of AMR profiles. Additionally, to demonstrate its real-world applicability, the RASP workflow was then applied to five faecal samples where a minimum of 47 E. coli per animal (239 total) were evaluated using an AMR indexing framework. ResultsFor each drug-rater-isolate combination in experiment A, there was a clear consensus of the MIC and deviation from the consensus remained within one doubling-dilution (the exception being gentamicin at two dilutions). Experiment B revealed a concordance correlation coefficient of 0.9670 (95%CI: 0.9670 - 0.9670) between the robot and human performed MICs. RASPs application to the five faecal samples highlighted the intra-animal diversity of gut commensal E. coli, identifying between five and nine unique isolate AMR phenotypes per sample. ConclusionsWhile adhering to internationally accepted guidelines, RASP was superior in throughput, cost and data resolution when compared to an experienced human technician. Integration of robotics platforms in the microbiology laboratory is a necessary advancement for future One-Health AMR endeavours.

microbiology↗

Examination of Australian Streptococcus suis Isolates From Clinically Affected Pigs in a Global Context and the Genomic Characterisation of ST1 as a Predictor of Virulence

Streptococcus suis is a major zoonotic pathogen that causes severe disease in both humans and pigs. In this study, we investigated S. suis from 148 cases of clinical disease in pigs from 46 pig herds over a period of seven years. These isolates underwent whole genome sequencing, genome analysis and antimicrobial susceptibility testing. Genome sequence data of Australian isolates was compared at the core genome level to clinical isolates from overseas. Results demonstrated eight predominant multi-locus sequence types and two major cps gene types (cps2 and 3). At the core genome level Australian isolates clustered predominantly within one large clade consisting of isolates from the UK, Canada and North America. In particular, serotype 2 MLST25 strains were very closely associated with Canadian and North American strains. A very small proportion of Australian swine isolates (5%) were phylogenetically associated with south-east Asian and UK isolates, many of which were classified as causing systemic disease, and derived from cases of human and swine disease. In addition, we show that ST1 clones carry a constellation of putative virulence genes not present in other Australian STs, and that this is mirrored in overseas ST1 clones. Based on this dataset we provide a comprehensive outline of the current S. suis clones associated with disease in Australian pigs and their global context, and discuss the implications this has on antimicrobial therapy, potential vaccine candidates and public health.\n\nImportanceIn this study, we examine in detail, the genomic characteristics of 148 Streptococcus suis isolates from clinically diseased Australian pigs. We report the antimicrobial susceptibility profiles, virulence gene analysis and relationship to isolates from other regions of the world. We also demonstrate that ST1 clones, regardless of serotype, carry a large array of putative virulence genes while maintaining a small total gene content. This compilation of data has major ramifications for vaccine development, and refines the understanding of the distribution of various strains of this potentially-fatal zoonotic agent in the global pig industry

microbiology↗