The California Department of Public Health (CDPH) reviewed 109 cases of healthcare personnel (HCP) with laboratory-confirmed mpox to understand transmission risk in healthcare settings. Overall, 90% of HCP with mpox had nonoccupational exposure risk factors. One occupationally acquired case was associated with sharps injury while unroofing a patient's lesion for diagnostic testing.

Chlorhexidine bathing to prevent transmission of multidrug-resistant organisms has been adopted by many U.S. hospitals, but increasing chlorhexidine use has raised concerns about possible emergence of resistance. We sought to establish a broth microdilution method for determining chlorhexidine MICs and then used the method to evaluate chlorhexidine MICs for bacteria that can cause health care-associated infections. We adapted a broth microdilution method for determining chlorhexidine MICs, poured panels, established quality control ranges, and tested Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae complex isolates collected at three U.S. sites. Chlorhexidine MICs were determined for 535 isolates including 129 S. aureus, 156 E. coli, 142 K. pneumoniae, and 108 E. cloacae complex isolates. The respective MIC distributions for each species ranged from 1 to 8 mg/L (MIC(50) = 2 mg/L and MIC(90) = 4 mg/L), 1 to 64 mg/L (MIC(50) = 2 mg/L and MIC(90) = 4 mg/L), 4 to 64 mg/L (MIC(50) = 16 mg/L and MIC(90) = 32 mg/L), and 1 to >64 mg/L (MIC(50) = 16 mg/L and MIC(90) = 64 mg/L). We successfully adapted a broth microdilution procedure that several laboratories were able to use to determine the chlorhexidine MICs of bacterial isolates. This method could be used to investigate whether chlorhexidine MICs are increasing. IMPORTANCE Chlorhexidine bathing to prevent transmission of multidrug-resistant organisms and reduce health care-associated infections has been adopted by many hospitals. There is concern about the possible unintended consequences of using this agent widely. One possible unintended consequence is decreased susceptibility to chlorhexidine, but there are not readily available methods to perform this evaluation. We developed a method for chlorhexidine MIC testing that can be used to evaluate for possible unintended consequences.

We describe a large SARS-CoV-2 outbreak involving an acute care hospital emergency department during December 2020 and January 2021, in which 27 healthcare personnel worked while infectious, resulting in multiple opportunities for SARS-CoV-2 transmission to patients and other healthcare personnel. We provide recommendations for improving infection prevention and control.

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. Participants included patients who developed bacterial infections following administration of umbilical cord blood-derived products marketed as stem cell treatment during August 2017 to September 2018. Data analysis was performed from March 2019 to September 2021. EXPOSURES: Umbilical cord blood-derived products marketed as stem cell treatment. MAIN OUTCOMES AND MEASURES: Data were collected on patient infections and exposures. The Centers for Disease Control and Prevention performed sterility testing on undistributed and distributed vials of product marketed as stem cell treatment and performed whole-genome sequencing to compare patient and product bacterial isolates. RESULTS: Culture-confirmed bacterial infections were identified in 20 patients (median [range] age, 63 [2-89] years; 13 male patients [65%]) from 8 US states who sought stem cell treatment for conditions including pain, osteoarthritis, rheumatoid arthritis, and injury; all but 1 required hospitalization. The most frequently isolated bacteria from patients with infections were common enteric species, including Escherichia coli (14 patients) and Enterobacter cloacae (7 patients). Of unopened, undistributed products sampled for testing, 65% (22 of 34 vials) were contaminated with at least 1 of 16 bacterial species, mostly enteric. A patient isolate from Arizona matched isolates obtained from products administered to patients in Florida, and patient isolates from Texas matched undistributed product sent from the company in California. CONCLUSIONS AND RELEVANCE: Unapproved stem cell products can expose patients to serious risks without proven benefit. Sequencing results suggest a common source of extensive contamination, likely occurring during the processing of cord blood into product. Patients and health care practitioners who are considering the use of unapproved products marketed as stem cell treatment should be aware of their unproven benefits and potential risks, including serious infections.

BACKGROUND: Candida auris, a multidrug-resistant yeast, can spread rapidly in ventilator-capable skilled-nursing facilities (vSNFs) and long-term acute care hospitals (LTACHs). In 2018, a laboratory serving LTACHs in southern California began identifying species of Candida that were detected in urine specimens to enhance surveillance of C auris, and C auris was identified in February 2019 in a patient in an Orange County (OC), California, LTACH. Further investigation identified C auris at 3 associated facilities. OBJECTIVE: To assess the prevalence of C auris and infection prevention and control (IPC) practices in LTACHs and vSNFs in OC. DESIGN: Point prevalence surveys (PPSs), postdischarge testing for C auris detection, and assessments of IPC were done from March to October 2019. SETTING: All LTACHs (n = 3) and vSNFs (n = 14) serving adult patients in OC. PARTICIPANTS: Current or recent patients in LTACHs and vSNFs in OC. INTERVENTION: In facilities where C auris was detected, PPSs were repeated every 2 weeks. Ongoing IPC support was provided. MEASUREMENTS: Antifungal susceptibility testing and whole-genome sequencing to assess isolate relatedness. RESULTS: Initial PPSs at 17 facilities identified 44 additional patients with C auris in 3 (100%) LTACHs and 6 (43%) vSNFs, with the first bloodstream infection reported in May 2019. By October 2019, a total of 182 patients with C auris were identified by serial PPSs and discharge testing. Of 81 isolates that were sequenced, all were clade III and highly related. Assessments of IPC identified gaps in hand hygiene, transmission-based precautions, and environmental cleaning. The outbreak was contained to 2 facilities by October 2019. LIMITATION: Acute care hospitals were not assessed, and IPC improvements over time could not be rigorously evaluated. CONCLUSION: Enhanced laboratory surveillance and prompt investigation with IPC support enabled swift identification and containment of C auris. PRIMARY FUNDING SOURCE: Centers for Disease Control and Prevention.

OBJECTIVE: To describe epidemiologic and genomic characteristics of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in a large skilled nursing facility (SNF), and the strategies that controlled transmission. DESIGN, SETTING, AND PARTICIPANTS: Cohort study during March 22-May 4, 2020 of all staff and residents at a 780-bed SNF in San Francisco, California. METHODS: Contact tracing and symptom screening guided targeted testing of staff and residents; respiratory specimens were also collected through serial point prevalence surveys (PPS) in units with confirmed cases. Cases were confirmed by real-time reverse transcription-polymerase chain reaction testing for SARS-CoV-2; whole genome sequencing (WGS) characterized viral isolate lineages and relatedness. Infection prevention and control (IPC) interventions included restricting from work any staff who had close contact to a confirmed case; restricting movements between units; implementing surgical face masking facility-wide; and recommended PPE (isolation gown, gloves, N95 respirator and eye protection) for clinical interactions in units with confirmed cases. RESULTS: Of 725 staff and residents tested through targeted testing and serial PPS, twenty-one (3%) were SARS-CoV-2-positive; sixteen (76%) staff and 5 (24%) residents. Fifteen (71%) were linked to a single unit. Targeted testing identified 17 (81%) cases; PPS identified 4 (19%). Most (71%) cases were identified prior to IPC intervention. WGS was performed on SARS-CoV-2 isolates from four staff and four residents; five were of Santa Clara County lineage and the three others were distinct lineages. CONCLUSIONS: Early implementation of targeted testing, serial PPS, and multimodal IPC interventions limited SARS-CoV-2 transmission within the SNF.

The Camp Fire, California's deadliest wildfire, began November 8, 2018, and was extinguished November 25 (1). Approximately 1,100 evacuees from the fire sought emergency shelter. On November 10, acute gastroenteritis (AGE) was reported in two evacuation shelters; norovirus illness was suspected, because it is commonly detected in shelter-associated AGE outbreaks. Norovirus is highly contagious and resistant to several disinfectants. Butte County Public Health Department (BCPHD), assisted by the California Department of Public Health (CDPH), initiated active surveillance to identify cases, confirm the etiology, and assess shelter infection prevention and control (IPC) practices to guide recommendations. During November 8-30, a total of 292 patients with AGE were identified among nine evacuation shelters; norovirus was detected in 16 of 17 unique patient stool specimens. Shelter IPC assessments revealed gaps in illness surveillance, isolation practices, cleaning, disinfection, and handwashing. CDPH and BCPHD collaborated with partner agencies to implement AGE screening, institute isolation protocols and 24-hour cleaning services, and promote proper hand hygiene. During disasters with limited resources, damaged infrastructure, and involvement of multiple organizations, establishing shelter disease surveillance and IPC is difficult. However, prioritizing effective surveillance and IPC at shelter activation is necessary to prevent, identify, and contain outbreaks.

On February 26, 2020, the first U.S. case of community-acquired coronavirus disease 2019 (COVID-19) was confirmed in a patient hospitalized in Solano County, California (1). The patient was initially evaluated at hospital A on February 15; at that time, COVID-19 was not suspected, as the patient denied travel or contact with symptomatic persons. During a 4-day hospitalization, the patient was managed with standard precautions and underwent multiple aerosol-generating procedures (AGPs), including nebulizer treatments, bilevel positive airway pressure (BiPAP) ventilation, endotracheal intubation, and bronchoscopy. Several days after the patient's transfer to hospital B, a real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) test for SARS-CoV-2 returned positive. Among 121 hospital A health care personnel (HCP) who were exposed to the patient, 43 (35.5%) developed symptoms during the 14 days after exposure and were tested for SARS-CoV-2; three had positive test results and were among the first known cases of probable occupational transmission of SARS-CoV-2 to HCP in the United States. Little is known about specific risk factors for SARS-CoV-2 transmission in health care settings. To better characterize and compare exposures among HCP who did and did not develop COVID-19, standardized interviews were conducted with 37 hospital A HCP who were tested for SARS-CoV-2, including the three who had positive test results. Performing physical examinations and exposure to the patient during nebulizer treatments were more common among HCP with laboratory-confirmed COVID-19 than among those without COVID-19; HCP with COVID-19 also had exposures of longer duration to the patient. Because transmission-based precautions were not in use, no HCP wore personal protective equipment (PPE) recommended for COVID-19 patient care during contact with the index patient. Health care facilities should emphasize early recognition and isolation of patients with possible COVID-19 and use of recommended PPE to minimize unprotected, high-risk HCP exposures and protect the health care workforce.

BACKGROUND: Candidemia is a common healthcare-associated bloodstream infection with high morbidity and mortality. There are no current estimates of candidemia burden in the United States. METHODS: In 2017, the Centers for Disease Control and Prevention (CDC) conducted active population-based surveillance for candidemia through the Emerging Infections Program (EIP) in 45 counties in nine states encompassing ~17 million persons (5% of the national population). Laboratories serving the catchment area population reported all blood cultures with Candida, and a standard case definition was applied to identify cases that occurred in surveillance area residents. Burden of cases and mortality was estimated by extrapolating surveillance area cases to national numbers using 2017 national census data. RESULTS: We identified 1,226 candidemia cases across nine surveillance sites in 2017. Based on this, we estimated 22,660 (95% confidence interval [CI]: 20,210-25,110) cases of candidemia occurred in the United States in 2017. Overall estimated incidence was 7.0 cases per 100,000 persons, with highest rates in adults >/=65 years (20.1/100,000), males (7.9/100,000), and those of black race (12.3/100,000). An estimated 3,380 (95% CI: 1,318-5,442) deaths occurred within seven days of a positive Candida blood culture and 5,628 (95% CI: 2,465-8,791) deaths occurred during the hospitalization with candidemia. CONCLUSIONS: Our analysis highlights the substantial burden of candidemia in the U.S. Because candidemia is only one form of invasive candidiasis, the true burden of invasive infections due to Candida is higher. Ongoing surveillance can support future burden estimates and help assess the impact of prevention interventions.

OBJECTIVES: Describe antibiotic use for urinary tract infection (UTI) among a large cohort of US nursing home residents. DESIGN: Analysis of data from a multistate, 1-day point prevalence survey of antimicrobial use performed between April and October 2017. SETTING AND PARTICIPANTS: Residents of 161 nursing homes in 10 US states of the Emerging Infections Program (EIP). METHODS: EIP staff reviewed nursing home medical records to collect data on systemic antimicrobial drugs received by residents, including therapeutic site, rationale for use, and planned duration. For drugs with the therapeutic site documented as urinary tract, pooled mean and nursing home-specific prevalence rates were calculated per 100 nursing home residents, and proportion of drugs by selected characteristics were reported. Data were analyzed in SAS, version 9.4. RESULTS: Among 15,276 residents, 407 received 424 antibiotics for UTI. The pooled mean prevalence rate of antibiotic use for UTI was 2.66 per 100 residents; nursing home-specific rates ranged from 0 to 13.6. One-quarter of antibiotics were prescribed for UTI prophylaxis, with a median planned duration of 111 days compared with 7 days when prescribed for UTI treatment (P < .001). Fluoroquinolones were the most common (18%) drug class used. CONCLUSIONS AND IMPLICATIONS: One in 38 residents was receiving an antibiotic for UTI on a given day, and nursing home-specific prevalence rates varied by more than 10-fold. UTI prophylaxis was common with a long planned duration, despite limited evidence to support this practice among older persons in nursing homes. The planned duration was >/=7 days for half of antibiotics prescribed for treatment of a UTI. Fluoroquinolones were the most commonly used antibiotics, despite their association with significant adverse events, particularly in a frail and older adult population. These findings help to identify priority practices for nursing home antibiotic stewardship.

OBJECTIVE: To evaluate the Orange County Clostridium difficile infection (CDI) prevention collaborative's effect on rates of CDI in acute-care hospitals (ACHs) in Orange County, California. DESIGN: Controlled interrupted time series. METHODS: We convened a CDI prevention collaborative with healthcare facilities in Orange County to reduce CDI incidence in the region. Collaborative participants received onsite infection control and antimicrobial stewardship assessments, interactive learning and discussion sessions, and an interfacility transfer communication improvement initiative during June 2015-June 2016. We used segmented regression to evaluate changes in monthly hospital-onset (HO) and community-onset (CO) CDI rates for ACHs. The baseline period comprised 17 months (January 2014-June 2015) and the follow-up period comprised 28 months (September 2015-December 2017). All 25 Orange County ACHs were included in the CO-CDI model to account for direct and indirect effects of the collaborative. For comparison, we assessed HO-CDI and CO-CDI rates among 27 ACHs in 3 San Francisco Bay Area counties. RESULTS: HO-CDI rates in the 15 participating Orange County ACHs decreased 4% per month (incidence rate ratio [IRR], 0.96; 95% CI, 0.95-0.97; P &lt; .0001) during the follow-up period compared with the baseline period and 3% (IRR, 0.97; 95% CI, 0.95-0.99; P = .002) per month compared to the San Francisco Bay Area nonparticipant ACHs. Orange County CO-CDI rates declined 2% per month (IRR, 0.98; 95% CI, 0.96-1.00; P = .03) between the baseline and follow-up periods. This decline was not statistically different from the San Francisco Bay Area ACHs (IRR, 0.97; 95% CI, 0.95-1.00; P = .09). CONCLUSIONS: Our analysis of ACHs in Orange County provides evidence that coordinated, regional multifacility initiatives can reduce CDI incidence.

INTRODUCTION: Staphylococcus aureus is one of the most common pathogens in health care facilities and in the community, and can cause invasive infections, sepsis, and death. Despite progress in preventing methicillin-resistant S. aureus (MRSA) infections in health care settings, assessment of the problem in both health care and community settings is needed. Further, the epidemiology of methicillin-susceptible S. aureus (MSSA) infections is not well described at the national level. METHODS: Data from the Emerging Infections Program (EIP) MRSA population surveillance (2005-2016) and from the Premier and Cerner Electronic Health Record databases (2012-2017) were analyzed to describe trends in incidence of hospital-onset and community-onset MRSA and MSSA bloodstream infections and to estimate the overall incidence of S. aureus bloodstream infections in the United States and associated in-hospital mortality. RESULTS: In 2017, an estimated 119,247 S. aureus bloodstream infections with 19,832 associated deaths occurred. During 2005-2012 rates of hospital-onset MRSA bloodstream infection decreased by 17.1% annually, but the decline slowed during 2013-2016. Community-onset MRSA declined less markedly (6.9% annually during 2005-2016), mostly related to declines in health care-associated infections. Hospital-onset MSSA has not significantly changed (p = 0.11), and community-onset MSSA infections have slightly increased (3.9% per year, p<0.0001) from 2012 to 2017. CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Despite reductions in incidence of MRSA bloodstream infections since 2005, S. aureus infections account for significant morbidity and mortality in the United States. To reduce the incidence of these infections further, health care facilities should take steps to fully implement CDC recommendations for prevention of device- and procedure-associated infections and for interruption of transmission. New and novel prevention strategies are also needed.

BACKGROUND: Outbreaks of health care-associated infections (HAIs) caused by Burkholderia cepacia complex (Bcc) have been associated with medical devices and water-based products. Water is the most common raw ingredient in nonsterile liquid drugs, and the significance of organisms recovered from microbiologic testing during manufacturing is assessed using a risk-based approach. This incident demonstrates that lapses in manufacturing practices and quality control of nonsterile liquid drugs can have serious unintended consequences. METHODS: An epidemiologic and laboratory investigation of clusters of Bcc HAIs that occurred among critically ill, hospitalized, adult and pediatric patients was performed between January 1, 2016, and October 31, 2016. RESULTS: One hundred and eight case patients with Bcc infections at a variety of body sites were identified in 12 states. Two distinct strains of Bcc were obtained from patient clinical cultures. These strains were found to be indistinguishable or closely related to 2 strains of Bcc obtained from cultures of water used in the production of liquid docusate, and product that had been released to the market by manufacturer X. CONCLUSIONS: This investigation highlights the ability of bacteria present in nonsterile, liquid drugs to cause infections or colonization among susceptible patients. Prompt reporting and thorough investigation of potentially related infections may assist public health officials in identifying and removing contaminated products from the market when lapses in manufacturing occur.

BACKGROUND: Clusters of bloodstream infections caused by Burkholderia cepacia and Stenotrophomonas maltophilia are uncommon, but have been previously identified in hemodialysis centers that reprocessed dialyzers for reuse on patients. We investigated an outbreak of bloodstream infections caused by B cepacia and S maltophilia among hemodialysis patients in clinics of a dialysis organization. STUDY DESIGN: Outbreak investigation, including matched case-control study. SETTING & PARTICIPANTS: Hemodialysis patients treated in multiple outpatient clinics owned by a dialysis organization. PREDICTORS: Main predictors were dialyzer reuse, dialyzer model, and dialyzer reprocessing practice. OUTCOMES: Case patients had a bloodstream infection caused by B cepacia or S maltophilia; controls were patients without infection dialyzed at the same clinic on the same day as a case; results of environmental cultures and organism typing. RESULTS: 17 cases (9 B cepacia and 8 S maltophilia bloodstream infections) occurred in 5 clinics owned by the same dialysis organization. Case patients were more likely to have received hemodialysis with a dialyzer that had been used more than 6 times (matched OR, 7.03; 95% CI, 1.38-69.76) and to have been dialyzed with a specific reusable dialyzer (Model R) with sealed ends (OR, 22.87; 95% CI, 4.49-infinity). No major lapses during dialyzer reprocessing were identified that could explain the outbreak. B cepacia was isolated from samples collected from a dialyzer header-cleaning machine from a clinic with cases and was indistinguishable from a patient isolate collected from the same clinic, by pulsed-field gel electrophoresis. Gram-negative bacteria were isolated from 2 reused Model R dialyzers that had undergone the facility's reprocessing procedure. LIMITATIONS: Limited statistical power and overmatching; few patient isolates and dialyzers available for testing. CONCLUSIONS: This outbreak was likely caused by contamination during reprocessing of reused dialyzers. Results of this and previous investigations demonstrate that exposing patients to reused dialyzers increases the risk for bloodstream infections. To reduce infection risk, providers should consider implementing single dialyzer use whenever possible.

OBJECTIVES: To assess hospitalisation risk factors and economic effects associated with a multistate hepatitis A outbreak in 2013. STUDY DESIGN: Retrospective case series. METHODS: Eligible outbreak-related cases confirmed by September 1, 2013, were defined as acute hepatitis symptoms and positive IgM anti-hepatitis A during March 15-August 12 among patients who consumed the food vehicle or had the outbreak genotype. We reviewed medical records, comparing demographic and clinical characteristics among hospitalized and non-hospitalized patients; we used logistic regression analysis to identify factors associated with hospitalization. We interviewed patients regarding symptom duration and healthcare usage and estimated per-patient and total costs. Health departments reported outbreak-related personnel hours. RESULTS: Medical records were reviewed for 147/159 (92%) eligible patients; median age was 48 (range: 1-84) years, and 64 (44%) patients were hospitalized. Having any chronic medical condition was independently associated with hospitalisation (odds ratio, 3.80; 95% confidence interval, 1.68-8.62). Interviews were completed for 114 (72%) eligible patients; estimated per-patient cost of healthcare and productivity loss was $13,467 for hospitalized and $2138 for non-hospitalized patients and $1,304,648 for all 165 outbreak-related cases. State and local public health personnel expenditures included 82 h and $3221/outbreak-related case. CONCLUSIONS: Hospitalisations in this outbreak were associated with chronic medical conditions and resulted in substantial healthcare usage and lost productivity. These data can be used to inform future evaluation of expansion of hepatitis A vaccination recommendations to include adults with chronic medical conditions.

BACKGROUND: We investigated an increase in Clostridium difficile infection (CDI) among pediatric oncology patients. METHODS: CDI cases were defined as first C difficile positive stool tests between December 1, 2010, and September 6, 2012, in pediatric oncology patients receiving inpatient or outpatient care at a single hospital. A case-control study was performed to identify CDI risk factors, infection prevention and antimicrobial prescribing practices were assessed, and environmental sampling was conducted. Available isolates were strain-typed by pulsed-field gel electrophoresis. RESULTS: An increase in hospital-onset CDI cases was observed from June-August 2012. Independent risk factors for CDI included hospitalization in the bone marrow transplant ward and exposure to computerized tomography scanning or cefepime in the prior 12 weeks. Cefepime use increased beginning in late 2011, reflecting a practice change for patients with neutropenic fever. There were 13 distinct strain types among 22 available isolates. Hospital-onset CDI rates decreased to near-baseline levels with enhanced infection prevention measures, including environmental cleaning and prolonged contact isolation. CONCLUSION: C difficile strain diversity associated with a cluster of CDI among pediatric oncology patients suggests a need for greater understanding of modes and sources of transmission and strategies to reduce patient susceptibility to CDI. Further research is needed on the risk of CDI with cefepime and its use as primary empirical treatment for neutropenic fever.

OBJECTIVE: From January 29 through February 5, 2013, a school district outside metropolitan Denver, Colorado, was closed because of absenteeism related to influenza-like illness (ILI) among students and staff. We evaluated the consequences and acceptability of the closure among affected households. METHODS: We conducted a household survey regarding parent or guardian employment and income interruptions, alternative child care arrangements, interruption of noneducational school services, ILI symptoms, student re-congregation, and communication preferences during the closure. RESULTS: Of the 35 (31%) of 113 households surveyed, the majority (28 [80%]) reported that the closure was not challenging. Seven (20%) households reported challenges: 5 (14%) reported that 1 or more adults missed work, 3 (9%) reported lost pay, and 1 (3%) reported challenges because of missed subsidized school meals. The majority (22 [63%]) of households reported that a hypothetical 1-month closure would not represent a problem; 6 of 8 households that did anticipate challenges reported that all adults worked outside the home. The majority (58%) of students visited at least 1 outside venue during the closure. CONCLUSIONS: A brief school closure did not pose a major problem for the majority of the affected households surveyed. School and public health officials should consider the needs of families in which all adults work outside the home when creating school closure contingency plans.

BACKGROUND: In May, 2013, an outbreak of symptomatic hepatitis A virus infections occurred in the USA. Federal, state, and local public health officials investigated the cause of the outbreak and instituted actions to control its spread. We investigated the source of the outbreak and assessed the public health measures used. METHODS: We interviewed patients, obtained their shopping information, and did genetic analysis of hepatitis A virus recovered from patients' serum and stool samples. We tested products for the virus and traced supply chains. FINDINGS: Of 165 patients identified from ten states, 69 (42%) were admitted to hospital, two developed fulminant hepatitis, and one needed a liver transplant; none died. Illness onset occurred from March 31 to Aug 12, 2013. The median age of patients was 47 years (IQR 35-58) and 91 (55%) were women. 153 patients (93%) reported consuming product B from retailer A. 40 patients (24%) had product B in their freezers, and 113 (68%) bought it according to data from retailer A. Hepatitis A virus genotype IB, uncommon in the Americas, was recovered from specimens from 117 people with hepatitis A virus illness. Pomegranate arils that were imported from Turkey-where genotype IB is common-were identified in product B. No hepatitis A virus was detected in product B. INTERPRETATION: Imported frozen pomegranate arils were identified as the vehicle early in the investigation by combining epidemiology-with data from several sources-genetic analysis of patient samples, and product tracing. Product B was removed from store shelves, the public were warned not to eat product B, product recalls took place, and postexposure prophylaxis with both hepatitis A virus vaccine and immunoglobulin was provided. Our findings show that modern public health actions can help rapidly detect and control hepatitis A virus illness caused by imported food. Our findings show that postexposure prophylaxis can successfully prevent hepatitis A illness when a specific product is identified. Imported food products combined with waning immunity in some adult populations might make this type of intervention necessary in the future.

Surveillance testing for Clostridium difficile among pediatric oncology patients identified stool colonization in 29% of patients without gastrointestinal symptoms and in 55% of patients with prior C. difficile infection (CDI). A high prevalence of C. difficile colonization and diarrhea complicates the diagnosis of CDI in this population.

OBJECTIVE: To investigate an outbreak of New Delhi metallo-beta-lactamase (NDM)-producing carbapenem-resistant Enterobacteriaceae (CRE) and determine interventions to interrupt transmission. Design, Setting, and Patients. Epidemiologic investigation of an outbreak of NDM-producing CRE among patients at a Colorado acute care hospital. METHODS: Case patients had NDM-producing CRE isolated from clinical or rectal surveillance cultures (SCs) collected during the period January 1, 2012, through October 20, 2012. Case patients were identified through microbiology records and 6 rounds of SCs in hospital units where they had resided. CRE isolates were tested by real-time polymerase chain reaction for blaNDM. Medical records were reviewed for epidemiologic links; relatedness of isolates was evaluated by pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). Infection control (IC) was assessed through staff interviews and direct observations. RESULTS: Two patients were initially identified with NDM-producing CRE during July-August 2012. A third case patient, admitted in May, was identified through microbiology records review. SC identified 5 additional case patients. Patients had resided in 11 different units before identification. All isolates were highly related by PFGE. WGS suggested 3 clusters of CRE. Combining WGS with epidemiology identified 4 units as likely transmission sites. NDM-producing CRE positivity in certain patients was not explained by direct epidemiologic overlap, which suggests that undetected colonized patients were involved in transmission. CONCLUSIONS: A 4-month outbreak of NDM-producing CRE occurred at a single hospital, highlighting the risk for spread of these organisms. Combined WGS and epidemiologic data suggested transmission primarily occurred on 4 units. Timely SC, combined with targeted IC measures, were likely responsible for controlling transmission.