A5035969706- Salmonella and Campylobacter epidemiology
- Antimicrobial Resistance in Staphylococcus
- Bacterial Identification and Susceptibility Testing
- Listeria monocytogenes in Food Safety
- Escherichia coli research studies
- Bacteriophages and microbial interactions
- Viral gastroenteritis research and epidemiology
- Streptococcal Infections and Treatments
- Mycobacterium research and diagnosis
- Vibrio bacteria research studies
- Enterobacteriaceae and Cronobacter Research
- Genomics and Phylogenetic Studies
- Identification and Quantification in Food
- Bacterial biofilms and quorum sensing
- Antifungal resistance and susceptibility
- Biological Research and Disease Studies
- Microbial infections and disease research
- Probiotics and Fermented Foods
- Gut microbiota and health
- Clostridium difficile and Clostridium perfringens research
- Celiac Disease Research and Management
- Viral Infections and Immunology Research
- Food Safety and Hygiene
- Molecular Biology Techniques and Applications
- Zoonotic diseases and public health
Centers for Disease Control and Prevention
2008-2023
Waterborne Environmental (United States)
2020-2023
Oak Ridge Associated Universities
2023
Oak Ridge Institute for Science and Education
2023
Tulane University
2023
National Center for Emerging and Zoonotic Infectious Diseases
2017-2018
Yale University
2010-2013
University of California, San Francisco
2004-2010
University of California, Berkeley
2008-2010
Brown University
2008
Background: Infection with multidrug-resistant, community-associated, methicillin-resistant Staphylococcus aureus (MRSA) has been reported but seems to be isolated. Objective: To determine the incidence of a multidrug-resistant MRSA clone (USA300) in San Francisco, and risk factors for infection. Design: Population-based survey cross-sectional study using chart review. Setting: 9 hospitals Francisco (population-based survey) 2 outpatient clinics Boston (cross-sectional study). Patients:...
The extent to which the horizontal transfer of virulence genes has contributed emergence contemporary virulent strains methicillin-resistant Staphylococcus aureus (MRSA) in hospital and community settings is poorly understood.Epidemiologically well-characterized MRSA isolates collected over 8.5 years were genotyped tested for presence 34 genes.Six strain types accounted 88.2% all infections. evolution phenotypes within CC8 CC30 lineages--2 background genomes that produced historical pandemic...
ABSTRACT Infections caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging as a major public health problem. CA-MRSA has been associated previously with skin and soft-tissue infection (SSTI) carriage of staphylococcal cassette chromosome mec (SCC ) type IV the Panton-Valentine leucocidin (PVL) virulence factor. To assess clonal distribution PVL-carrying strains association SSTI in San Francisco Bay area, we surveyed six collections S. isolates—671...
To define methicillin-resistant Staphylococcus aureus (MRSA) reservoirs in the community and their population dynamics, we studied molecular epidemiology of a random sample (n=490) from collection 2154 inpatient outpatient MRSA isolates during 7-year period San Francisco. We noted progressive replacement type II staphylococcal chromosomal cassette (SCC)mec-bearing with IV SCCmec-bearing isolates, which coincided >4-fold increase methicillin resistance between 1998 2002. Type involved...
Staphylococcus aureus clinical isolates obtained from patients who were inmates of the San Francisco County jail system showed an increase in prevalence methicillin-resistant (MRSA) 29%, 1997, to 74%, 2002; 91% MRSA carried staphylococcal chromosomal cassette mec (SCCmec) type IV. Pulsed field gel electrophoresis and multilocus sequence typing demonstrated 2 major clonal groups. One these groups is genetically indistinguishable strain responsible for outbreak Los Angeles 2002.
Epidemiological findings of a listeriosis outbreak in 2013 implicated Hispanic-style cheese produced by company A, and pulsed-field gel electrophoresis (PFGE) whole genome sequencing (WGS) were performed on clinical isolates representative collected from A environmental samples during the investigation. The results strengthened evidence for as vehicle. Surveillance sampling WGS 3 months later revealed that equipment purchased B yielded an isolate highly similar to all isolates. core...
Modern epidemiology of foodborne bacterial pathogens in industrialized countries relies increasingly on whole genome sequencing (WGS) techniques. As opposed to profiling techniques such as pulsed-field gel electrophoresis, WGS requires a variety computational methods. Since 2013, United States agencies responsible for food safety including the CDC, FDA, and USDA, have been performing whole-genome all Listeria monocytogenes found clinical, food, environmental samples. Each year, more genomes...
Nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA) plays a key role in the epidemiology and pathogenesis disease. The purpose this study was to determine characteristics dynamics nasal strains MRSA, as well their relation community-associated disease activity.This is cross-sectional survey molecular epidemiologic analysis colonization by S. homeless runaway youths, an underserved population at high risk for staphylococcal disease.Of 308 participants, 27.6% carried aureus,...
Abstract We describe a case of treatment failure caused by strain USA300 community-associated methicillin-resistant Staphylococcus aureus (MRSA) with intermediate susceptibility to vancomycin and reduced daptomycin. The was isolated from the bone 56-year-old man lumbar osteomyelitis after 6-week course for catheter-associated septic thrombophlebitis.
Foodborne non-typhoidal salmonellosis causes approximately 1 million illnesses annually in the USA. In April 2015, we investigated a multistate outbreak of 65 Salmonella Paratyphi B variant L(+) tartrate(+) infections associated with frozen raw tuna imported from Indonesia, which was consumed sushi. Forty-six (92%) 50 case-patients interviewed ate sushi during week before illness onset, and 44 (98%) 45 who specified containing tuna. Two strains were isolated samples Traceback identified...
Campylobacter is a leading causing of bacterial foodborne and zoonotic illnesses in the USA. Pulsed-field gene electrophoresis (PFGE) 7-gene multilocus sequence typing (MLST) have been historically used to differentiate sporadic from outbreak isolates. Whole genome sequencing (WGS) has shown provide superior resolution concordance with epidemiological data when compared PFGE MLST during investigations. In this study, we evaluated for high-quality SNP (hqSNP), core (cg)MLST whole (wg)MLST...
Genomic characterization of an Escherichia coli O157:H7 strain linked to leafy greens-associated outbreaks dates its emergence late 2015. One clade has notable accessory genomic content and a previously described mutation putatively associated with increased arsenic tolerance. This is reoccurring, emerging, or persistent causing illness over extended period.
In the United States, Shiga toxin-producing Escherichia coli (STEC) outbreaks cause >265,000 infections and cost $280 million annually. We investigated REPEXH01, a persistent strain of STEC O157:H7 associated with multiple sources, including romaine lettuce recreational water, that has caused since emerging in late 2015. By comparing genomes 729 REPEXH01 isolates those 2,027 other isolates, we identified highly conserved, single base pair deletion espW was strongly linked to membership. The...
Community-onset methicillin-resistant Staphylococcus aureus (CO-MRSA) skin and soft tissue infections (SSTI) are associated with SCCmec IV Panton-Valentine leukocidin (PVL) genes. CO-MRSA epidemiologic studies suggest that genotypic variation exists within one geographic region. We compared MRSA genotypes demographic clinical characteristics of patients SSTI between two regional medical centers. also examined factors PVL carriage. A total 279 isolates from 2000 to 2002 at San Francisco...
We describe the investigation of two temporally coincident illness clusters involving salmonella and Staphylococcus aureus in states. Cases were defined as gastrointestinal following meal events. Investigators interviewed ill persons. Stool, food environmental samples underwent pathogen testing. Alabama: Eighty cases identified. Median time from to was 5·8 h. Salmonella Heidelberg identified 27 28 stool specimens tested, coagulase-positive S. isolated three 16 Environmental indicated that...
is a leading cause of enteric bacterial illness in the United States. Traditional molecular subtyping methods, such as pulsed-field gel electrophoresis (PFGE) and 7-gene multilocus sequence typing (MLST), provided limited resolution to adequately identify
Abstract Objectives Vibrio cholerae remains a significant public health threat in Africa, with antimicrobial resistance (AMR) complicating treatment. This study leverages whole-genome sequencing (WGS) of V. isolates from Côte d’Ivoire, Ghana, Zambia and South Africa to assess genomic diversity, AMR profiles, virulence, demonstrating the utility WGS for enhanced surveillance within PulseNet network. Methods We analysed clinical environmental sources (2010–2024) using Oxford Nanopore hybracter...
Listeriosis is a serious foodborne infection that disproportionately affects elderly adults, pregnant women, newborns, and immunocompromised individuals. Diagnosis made by culturing Listeria monocytogenes from sterile body fluids or products of conception. This report describes the investigations two listeriosis pseudo-outbreaks caused contaminated laboratory media sheep blood.
Abstract Pathogen genomic data is increasingly important in investigations of infectious disease outbreaks. The objective this study to develop methods for using large-scale determine the type environment an outbreak pathogen came from. Specifically, focuses on assessing whether strain from a natural or experienced substantial laboratory culturing. approach uses phylogenetic analyses and machine learning identify DNA changes that are characteristic analysis include parallelized sequence read...