Publications by authors named "Maria Hoffmann"

Article Synopsis
  • * This study tested the effectiveness of Oxford Nanopore Technologies (ONT) for rapid and cost-efficient identification of foodborne pathogens, comparing various DNA extraction and sequencing methods.
  • * Results showed that ONT could accurately identify pathogens and their characteristics, but some variations in genome assembly were noted, indicating the need for further refinement of the process.
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As antimicrobial resistance (AMR) surveillance shifts to genomics, ensuring the quality of whole-genome sequencing (WGS) data produced across laboratories is critical. Participation in genomic proficiency tests (GPTs) not only increases individual laboratories' WGS capacity but also provides a unique opportunity to improve species-specific thresholds for WGS quality control (QC) by repeated resequencing of distinct isolates. Here, we present the results of the EU Reference Laboratory for Antimicrobial Resistance (EURL-AR) network GPTs of 2021 and 2022, which included 25 EU national reference laboratories (NLRs).

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Background: Oxford Nanopore provides high throughput sequencing platforms able to reconstruct complete bacterial genomes with 99.95% accuracy. However, even small levels of error can obscure the phylogenetic relationships between closely related isolates.

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Unlabelled: Wastewater surveillance has emerged as a crucial public health tool for population-level pathogen surveillance. Supported by funding from the American Rescue Plan Act of 2021, the FDA's genomic epidemiology program, GenomeTrakr, was leveraged to sequence SARS-CoV-2 from wastewater sites across the United States. This initiative required the evaluation, optimization, development, and publication of new methods and analytical tools spanning sample collection through variant analyses.

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Article Synopsis
  • - Foodborne outbreaks from Shiga toxin-producing E. coli (STEC) in wheat flour have become more common, prompting research into how different types of flour affect STEC survival during storage and heat treatment.
  • - Five types of wheat flour (whole, bleached, unbleached, bread, and self-rising) were inoculated with two STEC serovars (O121 and O157) and tested for bacterial persistence at room temperature over 42 days, revealing whole wheat flour had significantly lower STEC survival rates.
  • - Thermal resistance studies showed that while the type of flour did not greatly influence the survival of either STEC strain at various temperatures, O121 generally survived better than O157, with both
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is the leading cause of bacterial foodborne illness in the USA, with an estimated 95% of salmonellosis cases due to the consumption of contaminated food products. can cause several different disease syndromes, with the most common being gastroenteritis, followed by bacteremia and typhoid fever. Among the over 2,600 currently identified serotypes/serovars, some are mostly host-restricted and host-adapted, while the majority of serotypes can infect a broader range of host species and are associated with causing both livestock and human disease.

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Unlabelled: Unpaid caregivers of people living with dementia tend to suffer mental health problems as a result of the negative effects associated with the care tasks. Thus, psychosocial interventions for this population group are necessary. iSupport is an online support program for caregivers that was created by the World Health Organization.

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The global surveillance and outbreak investigation of antimicrobial resistance (AMR) is amidst a paradigm shift from traditional biology to bioinformatics. This is due to developments in whole-genome-sequencing (WGS) technologies, bioinformatics tools, and reduced costs. The increased use of WGS is accompanied by challenges such as standardization, quality control (QC), and data sharing.

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Methicillin-resistant Staphylococcus aureus (MRSA) infections cause substantive morbidity and mortality in neonates. Using publicly available resources from the National Center of Biotechnology Information (NCBI) and Food and Drug Administration's (FDA) GalaxyTrakr pipeline, we illustrate the dynamics of MRSA colonization and infection in neonates. Over 217 days of prospective surveillance, analyses revealed concurrent MRSA transmission chains affecting 11 of 17 MRSA-colonized patients (65%), with two clusters that demonstrated intervals of more than a month among the appearance of isolates.

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Background: The Salmonella enterica serovar Newport red onion outbreak of 2020 was the largest foodborne outbreak of Salmonella in over a decade. The epidemiological investigation suggested two farms as the likely source of contamination. However, single nucleotide polymorphism (SNP) analysis of the whole genome sequencing data showed that none of the Salmonella isolates collected from the farm regions were linked to the clinical isolates-preventing the use of phylogenetics in source identification.

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Escherichia coli ST1485 strains belong to the clinically important phylogroup F and have disseminated worldwide in humans, animals, and the environment. Here, we elucidated the pathogenome of a global collection of E. coli ST1485 isolates from diverse sources retrieved from public databases and a high-quality sequenced complete genome of colistin-resistant E.

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Low moisture foods (LMFs) have traditionally been recognized as safe for consumption, as most bacteria require higher water content to grow. However, outbreaks due to LMF foods are increasing, and the microbial pathogen is frequently implicated. can survive in LMFs for years, but few serovars have been studied, and the mechanisms which underlie this longevity are not well understood.

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The algal organic matter (AOM) is a problem in water treatment. Although the adsorption process is extensively applied to drinking water treatment, little information is known about the potential of new adsorbents to remove AOM. Herein, this work evaluated the removal of AOM and its main compounds (dissolved organic carbon (DOC), carbohydrate, and protein) by new adsorbents-mesoporous silica (SBA-16), graphene oxide material from citric acid (CA), and sugar (SU), and a composite of CA immobilized on sand (GSC).

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Salmonella enterica serovar Javiana is a major serovar that causes human infection in the United States. The complete genomic sequences of 9 Javiana isolates collected from food, environmental, and kratom sources in the United States were determined by hybrid assembly using Nanopore long-read sequencing and MiSeq short-read sequencing.

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Background: Cronobacter sakazakii is a foodborne pathogen that causes septicemia, meningitis, and necrotizing enterocolitis in neonates and infants. The current research details the full genome sequences of two extremely persistent C. sakazakii strains (H322 and GK1025B) isolated from powdered infant formula (PIF) manufacturing settings.

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Abstract: This multiagency report developed by the Interagency Collaboration for Genomics for Food and Feed Safety provides an overview of the use of and transition to whole genome sequencing (WGS) technology for detection and characterization of pathogens transmitted commonly by food and for identification of their sources. We describe foodborne pathogen analysis, investigation, and harmonization efforts among the following federal agencies: National Institutes of Health; Department of Health and Human Services, Centers for Disease Control and Prevention (CDC) and U.S.

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Listeria monocytogenes strains from different lineages show different biofilm-forming abilities. In this study, two strains of L. monocytogenes were whole genome sequenced using single-molecule real-time (SMRT) technology and characterized.

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Pistachios have been implicated in two salmonellosis outbreaks and multiple recalls in the U.S. This study performed an in-depth retrospective data analysis of Salmonella associated with pistachios as well as a storage study to evaluate the survivability of Salmonella on inoculated inshell pistachios to further understand the genetics and microbiological dynamics of this commodity-pathogen pair.

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Carbapenems-one of the important last-line antibiotics for the treatment of gram-negative infections-are becoming ineffective for treating infections. Studies have identified multiple genes (and mechanisms) responsible for carbapenem resistance. In some strains, the presence/absence of putative resistance genes is not consistent with their resistance phenotype-indicating the genomic factors underlying carbapenem resistance in are not fully understood.

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Peracetic acid (PAA) stands out as a safe and environmental-friendly oxidant and disinfectant which has been effectively used in wastewater treatment. Chemical oxygen demand (COD) is a very popular analysis in wastewater treatment; however, the interference of residual PAA on the COD measurement is still unknown. In this context, this study investigated the implications of applying the COD analysis in PAA-based treatment.

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Antibiotics are sprayed on apple and pear orchards to control, among other pathogens, the bacterium Erwinia amylovora, the causative agent of fire blight. As with many other pathogens, we observe the emergence of antibiotic-resistant strains of E. amylovora.

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Antimicrobial resistance (AMR) is a significant public health threat. With the rise of affordable whole genome sequencing, in silico approaches to assessing AMR gene content can be used to detect known resistance mechanisms and potentially identify novel mechanisms. To enable accurate assessment of AMR gene content, as part of a multi-agency collaboration, NCBI developed a comprehensive AMR gene database, the Bacterial Antimicrobial Resistance Reference Gene Database and the AMR gene detection tool AMRFinder.

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Plasmids play a major role in bacterial adaptation to environmental stress and often contribute to antibiotic resistance and disease virulence. Although the complete sequence of each plasmid is essential for studying plasmid biology, most antibiotic resistance and virulence plasmids in are present only in a low copy number, making extraction and sequencing difficult. Long read sequencing technologies require higher concentrations of DNA to provide optimal results.

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