Publications by authors named "Alison Halpin"

and are frequent causes of healthcare-associated infections. Antimicrobial-resistant enterococci pose a serious public health threat, particularly vancomycin-resistant enterococci (VRE), for which treatment options are limited. The Centers for Disease Control and Prevention's Division of Healthcare Quality Promotion Sentinel Surveillance system conducted surveillance from 2018 to 2019 to evaluate antimicrobial susceptibility profiles and molecular epidemiology of 205 and 180 clinical isolates collected from nine geographically diverse sites in the United States.

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Ice machines can harbor water-related organisms, and the use of ice or tap water for clinical care activities has been associated with infections in health care settings. During 2021-2022, a total of 23 cases of infection by Burkholderia multivorans (sequence type ST659) were reported at two southern California hospitals and linked to contaminated ice and water from ice machines. In addition to these 23 cases, this report also includes 23 previously unreported cases of B.

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Although antibiotics remain a cornerstone of modern medicine, the issues of widespread antibiotic resistance and collateral damage to the microbiome from antibiotic use are driving a need for drug developers to consider more tailored, patient-directed products to avoid antibiotic-induced perturbations of the structure and function of the indigenous microbiota. This perspective summarizes a cascade of microbiome health effects that is initiated by antibiotic-mediated microbiome disruption at an individual level and ultimately leads to infection and transmission of multidrug-resistant pathogens across patient populations. The scientific evidence behind each of the key steps of this cascade is presented.

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Antimicrobial resistance in healthcare-associated bacterial pathogens and the infections they cause are major public health threats affecting nearly all healthcare facilities. Antimicrobial-resistant bacterial infections can occur when colonizing pathogenic bacteria that normally make up a small fraction of the human microbiota increase in number in response to clinical perturbations. Such infections are especially likely when pathogens are resistant to the collateral effects of antimicrobial agents that disrupt the human microbiome, resulting in loss of colonization resistance, a key host defense.

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Distinguishing hypervirulent (hvKp) from classical (cKp) strains is important for clinical care, surveillance, and research. Some combinations of and are most commonly used, but it is unclear what combination of genotypic or phenotypic markers (e.g.

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Carbapenem-resistant (CRE) are an urgent public health threat. Genomic sequencing is an important tool for investigating CRE. Through the Division of Healthcare Quality Promotion Sentinel Surveillance system, we collected CRE and carbapenem-susceptible (CSE) from nine clinical laboratories in the USA from 2013 to 2016 and analysed both phenotypic and genomic sequencing data for 680 isolates.

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Nearly a century after the beginning of the antibiotic era, which has been associated with unparalleled improvements in human health and reductions in mortality associated with infection, the dwindling pipeline for new antibiotic classes coupled with the inevitable spread of antimicrobial resistance (AMR) poses a major global challenge. Historically, surveillance of bacteria with AMR typically relied on phenotypic analysis of isolates taken from infected individuals, which provides only a low-resolution view of the epidemiology behind an individual infection or wider outbreak. Recent years have seen increasing adoption of powerful new genomic technologies with the potential to revolutionise AMR surveillance by providing a high-resolution picture of the AMR profile of the bacteria causing infections and providing real-time actionable information for treating and preventing infection.

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Integration of genomic technologies into routine antimicrobial resistance (AMR) surveillance in health-care facilities has the potential to generate rapid, actionable information for patient management and inform infection prevention and control measures in near real time. However, substantial challenges limit the implementation of genomics for AMR surveillance in clinical settings. Through a workshop series and online consultation, international experts from across the AMR and pathogen genomics fields convened to review the evidence base underpinning the use of genomics for AMR surveillance in a range of settings.

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Unlabelled: Distinguishing hypervirulent (hvKp) from classical (cKp) strains is important for clinical care, surveillance, and research. Some combination of and are most commonly used, but it is unclear what combination of genotypic or phenotypic markers (e.g.

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During May 2018‒December 2022, we reviewed transfusion-transmitted sepsis cases in the United States attributable to polymicrobial contaminated apheresis platelet components, including Acinetobacter calcoaceticus‒baumannii complex or Staphylococcus saprophyticus isolated from patients and components. Transfused platelet components underwent bacterial risk control strategies (primary culture, pathogen reduction or primary culture, and secondary rapid test) before transfusion. Environmental samples were collected from a platelet collection set manufacturing facility.

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Background: Antimicrobial susceptibility testing (AST) is not routinely performed for Clostridioides difficile and data evaluating minimum inhibitory concentrations (MICs) are limited. We performed AST and whole genome sequencing (WGS) for 593 C. difficile isolates collected between 2012 and 2017 through the Centers for Disease Control and Prevention's Emerging Infections Program.

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During June 2017-November 2019, a total 36 patients with carbapenem-resistant Pseudomonas aeruginosa harboring Verona-integron-encoded metallo-β-lactamase were identified in a city in western Texas, USA. A faucet contaminated with the organism, identified through environmental sampling, in a specialty care room was the likely source for infection in a subset of patients.

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Article Synopsis
  • The CDC's Emerging Infections Program studied carbapenem-resistant Pseudomonas aeruginosa (CRPA) in the U.S. from 2016 to 2018 through population and laboratory surveillance, collecting 1,019 isolates for analysis.
  • The study found high genetic diversity among the strains, with 336 different sequence types, and the majority (87.1%) of isolates exhibited mutations in the porin OprD, linked to carbapenem resistance.
  • While only a small percentage contained carbapenemase genes, many had non-carbapenemase β-lactamase genes, indicating that other resistance mechanisms also play a significant role in the spread of CRPA in the U.S.
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  • The ongoing evolution of SARS-CoV-2 has led to new variants that heighten the severity of the COVID-19 pandemic, classified as variants of concern or interest (VOC/VOI) due to their impact on vaccine effectiveness.
  • A study analyzing 14 different variants found varying levels of resistance to neutralization by antibodies from vaccinated individuals, with the Omicron variant being the most adept at evading these defenses.
  • Despite Omicron's escape ability, individuals who received a booster vaccination still showed moderate effectiveness in neutralizing this variant, reinforcing the importance of vaccination in combating COVID-19.
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Healthcare-associated carbapenem-resistant (CRAB) infections are a serious threat associated with global epidemic clones and a variety of carbapenemase gene classes. In this study, we describe the molecular epidemiology, including whole-genome sequencing analysis and antimicrobial susceptibility profiles of 92 selected, nonredundant CRAB collected through public health efforts in the United States from 2013 to 2017. Among the 92 isolates, the Oxford (OX) multilocus sequence typing scheme identified 30 sequence types (STs); the majority of isolates ( = 59, 64%) represented STs belonging to the international clonal complex 92 (CC92).

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Background: Patients with ESKD on maintenance dialysis receive dialysis in common spaces with other patients and have a higher risk of severe SARS-CoV-2 infections. They may have persistently or intermittently positive SARS-CoV-2 RT-PCR tests after infection. We describe the clinical course of SARS-CoV-2 infection and the serologic response in a convenience sample of patients with ESKD to understand the duration of infectivity.

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and with resistance to daptomycin and/or linezolid are emerging globally. We present the genomic characterization of daptomycin- and linezolid-resistant and surveillance isolates from the United States, 2013-2016. Daptomycin resistance was low among (2/364, 0.

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Article Synopsis
  • Genomic surveillance is essential for monitoring emerging SARS-CoV-2 variants, which can impact public health by affecting transmissibility and immune response.
  • Between June 2021 and January 2022, the CDC enhanced its data collection methods to provide more accurate estimates of variant proportions by utilizing public repositories and refining analysis techniques.
  • During this time, the Delta variant initially dominated infections but was quickly supplanted by the Omicron variant, which accounted for nearly all U.S. cases by January 2022, highlighting the need for ongoing surveillance in pandemic response.
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Carbapenem-resistant Pseudomonas aeruginosa (CRPA) producing the Verona integron‒encoded metallo-β-lactamase (VIM) are highly antimicrobial drug-resistant pathogens that are uncommon in the United States. We investigated the source of VIM-CRPA among US medical tourists who underwent bariatric surgery in Tijuana, Mexico. Cases were defined as isolation of VIM-CRPA or CRPA from a patient who had an elective invasive medical procedure in Mexico during January 2018‒December 2019 and within 45 days before specimen collection.

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Article Synopsis
  • - A study was conducted on nursing home residents who were infected with SARS-CoV-2 to analyze immune responses in both plasma and gingival crevicular fluid (GCF) during and after their infection.
  • - 14 residents participated, with antibody levels measured at multiple time points; results showed that most participants had robust immune responses, with key antibodies detected in both plasma and GCF.
  • - The findings suggest that GCF could be a noninvasive and effective way to monitor immune responses to SARS-CoV-2, especially in individuals who may have difficulty with blood draws.
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Importance: The number of clinics marketing stem cell products for joint diseases, chronic pain, and most recently, COVID-19, has increased despite warnings from the US Food and Drug Administration that stem cell products for these and other indications have not been proven safe or effective.

Objective: To examine bacterial infections in 20 patients who received umbilical cord blood-derived products marketed as stem cell treatment.

Design, Setting, And Participants: This case series is a national public health investigation including case-finding, medical record review and abstraction, and laboratory investigation, including sterility testing of products and whole-genome sequencing of patient and product isolates.

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Carbapenemase gene-positive (CP) Gram-negative bacilli are of significant clinical and public health concern. Their rapid detection and containment are critical to preventing their spread and additional infections they can cause. To this end, CDC developed the Antibiotic Resistance Laboratory Network (AR Lab Network), in which public health laboratories across all 50 states, several cities, and Puerto Rico characterize clinical isolates of carbapenem-resistant (CRE), Pseudomonas aeruginosa (CRPA), and Acinetobacter baumannii (CRAB) and conduct colonization screens to detect the presence of mobile carbapenemase genes.

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