Research Publications (Food Safety)

Influenza is a major global public health threat as a result of its highly pathogenic variants, large zoonotic reservoir, and pandemic potential. Metagenomic viral sequencing offers the potential for a diagnostic test for influenza virus which also provides insights on transmission, evolution, and drug resistance and simultaneously detects other viruses. We therefore set out to apply the Oxford Nanopore Technologies sequencing method to metagenomic sequencing of respiratory samples.

Polymyxin antibiotics are a last-line treatment for multidrug-resistant Gram-negative bacteria. However, the emergence of colistin resistance, including the spread of mobile mcr genes, necessitates the development of improved diagnostics for the detection of colistin-resistant organisms in hospital settings.

Blood cultures are routinely collected in pairs of aerobic and anaerobic bottles. Artificial sterilization of Gram-negative bacteria in aerobic bottles containing clinically meaningful antibiotic concentrations has previously been observed. This study assessed recovery from anaerobic bottles with and without antibiotic binding resins.

Enterobacteriaceae represent a diverse and medically important family of bacteria that are difficult to identify to the species level using the standard molecular method of 16S rRNA gene sequencing. Prior work has demonstrated the value of dnaJ gene sequence analysis in resolving different members of the family. However, existing protocols are not optimized for clinical use and exhibit several limitations in practice.

Genomic surveillance that combines bacterial sequencing and epidemiological information will become the gold standard for outbreak detection, but its clinical translation is hampered by the lack of automated interpretation tools. We performed a prospective pilot study to evaluate the analysis of methicillin-resistant Staphylococcus aureus (MRSA) genomes using the Next Gen Diagnostics (NGD) automated bioinformatics system.

Pathogen cell-free DNA (pcfDNA) in blood and urine is an attractive biomarker; however, the impact of preanalytical factors is not well understood.

Rifampin heteroresistance—where rifampin-resistant and -susceptible tuberculosis (TB) bacilli coexist—may result in failed standard TB treatment and potential spread of rifampin-resistant strains. The detection of rifampin heteroresistance in routine rapid diagnostic tests (RDTs) allows for patients to receive prompt and effective multidrug-resistant-TB treatment and may improve rifampin-resistant TB control.

There are sparse data to indicate the extent that macrolide-resistant Mycoplasma pneumoniae (MRMp) occurs in the United States or its clinical significance. Between 2015 and 2018, hospitals in 8 states collected and stored respiratory specimens that tested positive for M. pneumoniae and sent them to the University of Alabama at Birmingham, where real-time PCR was performed for detection of 23S rRNA mutations known to confer macrolide resistance.

Mycoplasma genitalium causes a common sexually transmitted infection with a marked propensity to develop antimicrobial resistance. As few treatment options exist, this poses significant challenges to clinicians. Recent diagnostic advances have resulted in tests that report the simultaneous detection of M. genitalium and any resistance to macrolides, the first-line treatment. This allows for therapy to be tailored to the individual, thereby optimizing treatment outcomes.

Blood culture bottles containing antibiotic binding resins are routinely used to minimize artificial sterilization in the presence of antibiotics. However, the resin binding kinetics can differ between antibiotics and concentrations.

Shiga toxin-producing Escherichia coli (STEC) and the STEC subgroup enterohemorrhagic E. coli cause intestinal infections with symptoms ranging from watery diarrhea to hemolytic-uremic syndrome (HUS). A key tool for the epidemiological differentiation of STEC is serotyping. The serotype in combination with the main virulence determinants gives important insight into the virulence potential of a strain.

Clostridioides (Clostridium) difficile infection (CDI) is the most common causative pathogen of health care-associated gastrointestinal infections; however, due to the overlap of clinical symptoms with those of other causes of acute gastroenteritis, the selection of the most appropriate laboratory test is difficult. From April to October 2018, 640 stool samples requested for CDI testing were examined using the mariPOC CDI and Gastro test (ArcDia), which allows the detection of C.

With multidrug-resistant (MDR) Enterobacterales on the rise, a nontoxic antimicrobial agent with a unique mechanism of action such as fosfomycin seems attractive. However, establishing accurate fosfomycin susceptibility testing for non-Escherichia coli isolates in a clinical microbiology laboratory remains problematic.

Colistin has become increasingly important in the treatment of multidrug-resistant Gram-negative bacteria. Resistance to colistin has emerged globally, necessitating the need for an accurate method to detect colistin resistance. The colistin NP test has shown promise as a rapid screening assay for colistin resistance.

Due to the atypical serological profile of some patients with primary Q fever infection who do not develop IgM against Coxiella burnetii, we developed an avidity test to distinguish recent or past infections. We tested 39 serum samples by immunofluorescence with conventional assay and after urea treatment from 26 patients at different stages of the disease.

Recommendations for first-line and second-line drug testing and organism group, specific methodologies, and reporting recommendations have been addressed by the Clinical and Laboratory Standards Institute (CLSI) and are important in the selection of appropriate antimicrobial treatment regimens for nontuberculous mycobacteria (NTM) disease.

The multidrug-resistant yeast pathogen Candida auris continues to cause outbreaks and clusters of clinical cases worldwide. Previously, we developed a real-time PCR assay for the detection of C. auris from surveillance samples (L. Leach, Y. Zhu, and S. Chaturvedi, J Clin Microbiol 56:e01223-17, 2018, https://doi.org/10.1128/JCM.01223-17). The assay played a crucial role in the ongoing investigations of the C. auris outbreak in New York City.

Urinalysis (UA) has routinely been used as a screening tool prior to urine culture set up. BacterioScan 216Dx is an FDA-cleared semiautomated system to detect bacterial growth in urine. The aim of this study was to evaluate 216Dx in comparison to UA for diagnosis of urinary tract infection (UTI) in children.

Laboratory surveillance plays an important role in the detection and control of hepatitis A outbreaks and requires the application of rapid and accurate molecular diagnostic tools for hepatitis A virus (HAV) RNA detection, subgenotype identification, and sequence-based genotyping.

The conventional methodology for gastrointestinal pathogen detection remains time-consuming, expensive, and of limited sensitivity. The objective of this study was to evaluate the performance of the BD Max enteric viral panel (Max EVP) assay for identification of viral pathogens in stool specimens from individuals with symptoms of acute gastroenteritis, enteritis, or colitis.

Laboratory surveillance plays an important role in the detection and control of hepatitis A outbreaks and requires the application of rapid and accurate molecular diagnostic tools for hepatitis A virus (HAV) RNA detection, subgenotype identification, and sequence-based genotyping.

The conventional methodology for gastrointestinal pathogen detection remains time-consuming, expensive, and of limited sensitivity. The objective of this study was to evaluate the performance of the BD Max enteric viral panel (Max EVP) assay for identification of viral pathogens in stool specimens from individuals with symptoms of acute gastroenteritis, enteritis, or colitis.

Quality management and independent assessment of high-throughput sequencing-based virus diagnostics have not yet been established as a mandatory approach for ensuring comparable results. The sensitivity and specificity of viral high-throughput sequence data analysis are highly affected by bioinformatics processing using publicly available and custom tools and databases and thus differ widely between individuals and institutions.

Due to Australia’s management of antimicrobial use in poultry, particularly the discontinued use of avoparcin for nearly 20 years, it is hypothesized that vancomycin-resistant enterococci associated with human disease are not derived from poultry isolates.

Although enteric multianalyte syndromic panels are increasingly employed, direct comparisons with traditional methods and the inclusion of host phenotype correlations are limited. Luminex xTAG gastrointestinal pathogen panel (GPP) and culture results are highly concordant. However, phenotypic and microbiological confirmatory testing raises concerns regarding the accuracy of the GPP, especially for Salmonella spp.