Healthcare Exposure Research Articles

Racial and Ethnic Disparities in COVID-19-Related Infections, Hospitalizations, and Deaths : A Systematic Review.

Data suggest that the effects of coronavirus disease 2019 (COVID-19) differ among U.S. racial/ethnic groups. To evaluate racial/ethnic disparities in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates and COVID-19 outcomes, factors contributing to disparities, and interventions to reduce them. English-language articles in MEDLINE, PsycINFO, CINAHL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus, searched from inception through 31 August 2020. Gray literature sources were searched through 2 November 2020. Observational studies examining SARS-CoV-2 infections, hospitalizations, or deaths by race/ethnicity in U.S. settings. Single-reviewer abstraction confirmed by a second reviewer; independent dual-reviewer assessment of quality and strength of evidence. 37 mostly fair-quality cohort and cross-sectional studies, 15 mostly good-quality ecological studies, and data from the Centers for Disease Control and Prevention and APM Research Lab were included. African American/Black and Hispanic populations experience disproportionately higher rates of SARS-CoV-2 infection, hospitalization, and COVID-19-related mortality compared with non-Hispanic White populations, but not higher case-fatality rates (mostly reported as in-hospital mortality) (moderate- to high-strength evidence). Asian populations experience similar outcomes to non-Hispanic White populations (low-strength evidence). Outcomes for other racial/ethnic groups have been insufficiently studied. Health care access and exposure factors may underlie the observed disparities more than susceptibility due to comorbid conditions (low-strength evidence). Selection bias, missing race/ethnicity data, and incomplete outcome assessments in cohort and cross-sectional studies must be considered. In addition, adjustment for key demographic covariates was lacking in ecological studies. African American/Black and Hispanic populations experience disproportionately higher rates of SARS-CoV-2 infection and COVID-19-related mortality but similar rates of case fatality. Differences in health care access and exposure risk may be driving higher infection and mortality rates. Department of Veterans Affairs, Veterans Health Administration, Health Services Research & Development. (PROSPERO: CRD42020187078).

Abstract IA45: Genomics contributors to tumor subtypes in African American prostate and breast cancer patients

Abstract African Americans suffer disproportionally in higher cancer incidence and worse overall survival in a number of cancer types. The reasons for the disparities are multifactorial and include differences in access to healthcare and lifestyle exposures, delayed disease diagnosis in socio-economically deprived communities, tumor biological differences, and factors related to genetics. Recent findings from multiple prostate and breast cancer genomics studies have identified subsets of ancestry associated genes that are associated with worse outcomes. Therefore, we will present an overview of these recent findings from our lab and others, specifically focusing on how these driver genes function a subset of tumors. Additionally, we will provide examples of how these ancestry-associated genes are integrated within regulatory networks, and discuss the possibility of ancestry specific subtypes promote aggressive disease in African American breast and prostate cancer patients. Citation Format: Clayton Yates. Genomics contributors to tumor subtypes in African American prostate and breast cancer patients [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr IA45.

The Burden of Clostridioides Difficile Infection during the COVID-19 Pandemic: A Retrospective Case-Control Study in Italian Hospitals (CloVid)

Data on the burden of Clostridioides difficile infection (CDI) in Coronavirus Disease 2019 (COVID-19) patients are scant. We conducted an observational, retrospective, multicenter, 1:3 case (COVID-19 patients with CDI)-control (COVID-19 patients without CDI) study in Italy to assess incidence and outcomes, and to identify risk factors for CDI in COVID-19 patients. From February through July 2020, 8402 COVID-19 patients were admitted to eight Italian hospitals; 38 CDI cases were identified, including 32 hospital-onset-CDI (HO-CDI) and 6 community-onset, healthcare-associated-CDI (CO-HCA-CDI). HO-CDI incidence was 4.4 × 10,000 patient-days. The percentage of cases recovering without complications at discharge (i.e., pressure ulcers, chronic heart decompensation) was lower than among controls (p = 0.01); in-hospital stays was longer among cases, 35.0 versus 19.4 days (p = 0.0007). The presence of a previous hospitalisation (p = 0.001), previous steroid administration (p = 0.008) and the administration of antibiotics during the stay (p = 0.004) were risk factors associated with CDI. In conclusions, CDI complicates COVID-19, mainly in patients with co-morbidities and previous healthcare exposures. Its association with antibiotic usage and hospital acquired bacterial infections should lead to strengthen antimicrobial stewardship programmes and infection prevention and control activities.

Examining the impact of a penicillin allergy skin testing brochure on inpatient perceptions: A pre-post intervention study

The penicillin (PCN) allergy label is associated with serious and significant clinical consequences, including increased health care exposure, bacterial resistance, and suboptimal clinical outcomes.1,2 Despite these risks and the well-described waning of immunoglobulin E (IgE) antibodies over time, only 0.1% of patients labeled penicillin-allergic undergo penicillin skin testing (PST) annually.3 The underutilization of PCN allergy evaluations and subsequent PST may be partially related to knowledge gaps among both health care providers and patients, which has been described in the literature.

A Survey of Patient Perspectives on Approach to Health Care: Focus on Physician Competency and Compassion.

We conducted a cross-sectional, survey study of 764 volunteers to gain insight into patients’ perceptions of physician qualities of compassion and competence. Among 651 (85% response rate) survey participants, mean age was 52.4 (SD 21.4) years, 70.8% (n = 458) were female, and 84% (n = 539) identified as white. Predictors of compassion over competence included female gender (adjusted odds ratio [aOR] = 1.4, 95% CI: 1.04-1.89) and whether the respondent had a personal connection to the vignette (aOR = 1.24, 95% CI: 1.0-1.53). Thematic analysis demonstrated that preferences were influenced by: (a) explicit beliefs regarding the value of physician compassion and physician competence; (b) impact of emotional and mental health on medical experiences; (c) the type and frequency of health care exposure; and (d) perceived role of the physician in various clinical vignettes. Patients had wide-ranging, complex opinions on the qualities they valued in their physicians. These findings suggest that patients are engaged and can provide critical thoughtful feedback on the practice and delivery of health care.

Evaluation of viral co-infections among patients with community-associated Clostridioides difficile infection.

We assessed viral co-infections in 155 patients with community-associated Clostridioides difficile infection in five U.S. sites during December 2012–February 2013. Eighteen patients (12%) tested positive for norovirus (n = 10), adenovirus (n = 4), rotavirus (n = 3), or sapovirus (n = 1). Co-infected patients were more likely than non-co-infected patients to have nausea or vomiting (56% vs 31%; p = 0.04), suggesting that viral co-pathogens contributed to symptoms in some patients. There were no significant differences in prior healthcare or medication exposures or in CDI complications.

SARS-CoV-2 seroprevalence among health care workers in a New York City hospital: A cross-sectional analysis during the COVID-19 pandemic

BackgroundNew York City (NYC) has endured the greatest burden of COVID-19 infections in the US. Health inequities in South Bronx predisposed this community to a large number of infectious cases, hospitalizations, and mortality. Health care workers (HCWs) are at a high risk of exposure to the infection. This study aims to assess seroprevalence and the associated characteristics of consenting HCWs from an NYC public hospital. MethodsThis cross-sectional study includes serum samples for qualitative SARS-CoV-2 antibody testing with nasopharyngeal swabs for SARS-CoV-2; PCR and completion of an online survey capturing demographics, COVID-19 symptoms during the preceding months on duty, details of healthcare and community exposure, and travel history were collected from consenting participants in May 2020. Participants' risk of exposure to COVID-19 infection in the hospital and in the community was defined based on CDC guidelines. Travel history to high-risk areas was also considered an additional risk. The Odds Ratio with bivariable and multivariable logistic regression was used to assess characteristics associated with seroprevalence. ResultsA total of 500 HCW were tested, 137 (27%) tested positive for the SARS-CoV-2 antibody. Symptomatic participants had a 75% rate of seroconversion compared to those without symptoms. Subjects with anosmia and ageusia had increased odds of seroconversion in comparison to those without these symptoms. Community exposure was 34% among those who had positive antibodies. ConclusionSeroprevalence among HCWs was high compared to the community at the epicenter of the pandemic. Further studies to evaluate sustained adaptive immunity in this high-risk group will guide our response to a future surge.

S2321 Use of a Lumen-Apposing Metal Stent for a Colo-Colonic Stricture in the Time of COVID-19

INTRODUCTION: Anastomotic strictures are a known complication of colon resections. Risk factors include neoadjuvant chemo-radiation, anastomotic leak, diverting stoma and stapled anastomosis. Endoscopic balloon dilation is the first line intervention for anastomotic strictures but often requires several treatment sessions and associated healthcare system exposure. We describe a case of a colorectal anastomotic stricture treated with a lumen apposing metal stent (LAMS) with the purpose of decreasing frequency of endoscopic therapy during the initial outbreak of COVID-19. CASE DESCRIPTION/METHODS: A 51 year old female presented for management of a colo-colonic anastomotic stricture. She underwent a low anterior resection for stage III rectal cancer, complicated by an anastomotic leak requiring a diverting loop ileostomy. She then completed adjuvant XRT and FOLFOX therapy. She presented for evaluation 6 months after the creation of her loop ileostomy to consider reversal. During endoscopy, a severe stricture was found which could not be traversed even with a 15 Fr gastroscope. Initial dilation to 10mm with a balloon dilator was successful. One week later, the stricture was improved but still severe. A 15 mm by 10 mm LAMS was placed with the intent of decreasing the number of required procedures and healthcare system exposure during the initial outbreak of COVID-19. The stent was removed 6 weeks later, and the underlying stricture was markedly improved to a diameter of 15 mm, easily traversable with a gastroscope. The patient did not experience any complications while the stent was in place and was able to proceed with planning for ostomy reversal. DISCUSSION: Endoscopic balloon dilation is the initial intervention for anastomotic strictures. Serial balloon dilations usually require multiple procedures to achieve a durable response. With the uncertainty caused by the recent outbreak of COVID-19, many physicians and patients are looking for ways to decrease exposure to healthcare centers. Although LAMS are approved for the management of pancreatic fluid collections, they have been described as an alternative therapy for luminal GI strictures. This case demonstrates early adoption of LAMS with successful luminal dilation of an anastomotic stricture during the COVID-19 pandemic in an effort to decrease healthcare exposure and PPE use during an unprecedented time.Figure 1.: Colo-colonic anastomotic stricture prior to dilation.Figure 2.: LAMS 6 weeks after initial placement.Figure 3.: Stricture after LAMS removal.

Characteristics Associated With Invasive Staphylococcus aureus Infection Rates in Nursing Homes, Emerging Infections Program

Background: Most invasive methicillin-resistant Staphylococcus aureus (iMRSA) infections have onset in the community but are associated with healthcare exposures. More than 25% of cases with healthcare exposure occur in nursing homes (NHs) where facility-specific iMRSA rates vary widely. We assessed associations between nursing home characteristics and iMRSA incidence rates to help target prevention efforts in NHs. Methods: We used active, laboratory- and population-based surveillance data collected through the Emerging Infections Program during 2011–2015 from 25 counties in 7 states. NH-onset cases were defined as isolation of MRSA from a normally sterile site in a surveillance area resident who was in a NH within 3 days before the index culture. We calculated MRSA incidence (cases per NH resident day) using Centers for Medicare & Medicaid Services (CMS) skilled nursing facility cost reports and described variation in iMRSA incidence by NH. We used Poisson regression with backward selection, assessing variables for collinearity, to estimate adjusted rate ratios (aRRs) for NH characteristics (obtained from the CMS minimum dataset) associated with iMRSA rates. Results: Of 590 surveillance area NHs included in analysis, 89 (15%) had no NH-onset iMRSA infections. Rates ranged from 0 to 23.4 infections per 100,000 resident days. Increased rate of NH-onset iMRSA infection occurred with increased percentage of residents in short stay ≤30 days (aRR, 1.09), exhibiting wounds or infection (surgical wound [aRR, 1.08]; vascular ulcer/foot infection [aRR, 1.09]; multidrug-resistant organism infection [aRR, 1.13]; receipt of antibiotics [aRR, 1.06]), using medical devices or invasive support (ostomy [aRR, 1.07]; dialysis [aRR, 1.07]; ventilator support [aRR, 1.17]), carrying neurologic diagnoses (cerebral palsy [aRR, 1.14]; brain injury [aRR, 1.1]), and demonstrating debility (requiring considerable assistance with bed mobility [aRR, 1.05]) (Table). iMRSA rates decreased with increased percentage of residents receiving influenza vaccination (aRR, 0.96) and with the presence of any patients in isolation for any active infection (aRR, 0.83). Conclusions: iMRSA incidence varies greatly across nursing homes, with many NH patient and facility characteristics associated with NH-onset iMRSA rate differences. Some associations (short stay, wounds and infection, medical device use and invasive support) suggest that targeted interventions utilizing known strategies to decrease transmission may help to reduce infection rates, while others (neurologic diagnoses, influenza vaccination, presence of patients in isolation) require further exploration to determine their role. These findings can help identify NHs in other areas more likely to have higher rates of NH-onset iMRSA who could benefit from interventions to reduce infection rates.Funding: NoneDisclosures: None

A Growing Concern: The Emergence and Dissemination of Carbapenemase-producing Enterobacterales (CPE) in Canada

Background: Carbapenemase-producing Enterobacterales (CPE) have rapidly become a global health concern and are associated with substantial morbidity and mortality due to limited treatment options. Travel to endemic areas, especially healthcare exposure in these areas, is an important risk factor for acquisition. We describe the evolving epidemiology, molecular features, and outcomes of CPE in Canada through surveillance by the Canadian Nosocomial Infection Surveillance Program (CNISP). Methods: CNISP has conducted surveillance for CPE among inpatients and outpatients of all ages since 2010. Participating acute-care facilities submit eligible specimens to the National Microbiology Laboratory for detection of carbapenemase production, and epidemiological data are collected. Incidence rates per 10,000 patient days are calculated based on inpatient data. Results: In total, 59 CNISP hospitals in 10 Canadian provinces representing 21,789 beds and 6,785,013 patient days participated in this surveillance. From 2010 to 2018, 118 (26%) CPE-infected and 547 (74%) CPE-colonized patients were identified. Few pediatric cases were identified (n = 18). Infection incidence rates remain low and stable (0.02 per 10,000 patient days in 2010 to 0.03 per 10,000 patient days in 2018), and colonization incidence rates have increased by 89% over the surveillance period. Overall, 92% of cases were acquired in a healthcare facility: 61% (n = 278) in a Canadian healthcare facility and 31% (n = 142) in a healthcare facility outside Canada. Of the 8% of cases not acquired in a healthcare facility, 50% (16 of 32) reported travel outside of Canada in the 12 months prior to positive culture. The distribution of carbapenemases varied by region; New Delhi metallo-B-lactamase (NDM) was dominant (59%) in western Canada and Klebsiella pneumoniae carbapenemase (KPC) (66%) in central Canada. NDM and class D carbapenemase OXA-48 were more commonly identified among those who traveled outside of Canada, whereas KPC was more commonly identified among patients without travel. In addition, 30-day all-cause mortality was 14% (25 of 181) among CPE infected patients and 32% (14 of 44) among those with bacteremia. Conclusions: CPE rates remain low in Canada; however, national surveillance data suggest that the increase in CPE in Canada is now being driven by local nosocomial transmission as well as travel and healthcare within endemic areas. Changes in screening practices may have contributed to the increase in colonizations; however, these data are currently lacking and will be collected moving forward. These data highlight the need to intensify surveillance and coordinate infection control measures to prevent further spread of CPE in Canadian acute-care hospitals.Funding: NoneDisclosures: Susy Hota reports contracted research for Finch Therapeutics. Allison McGeer reports funds to her institution for projects for which she is the principal investigator from Pfizer and Merck, as well as consulting fees from the following companies: Sanofi-Pasteur, Sunovion, GSK, Pfizer, and Cidara.

Use of Health Information Exchange Improved the Identification of Healthcare-Associated Group A Streptococcus Infections

Background: Healthcare-associated group A Streptococcus (GAS) infections can cause severe morbidity and death. Invasive GAS is a reportable condition in the 5-county metropolitan area of Denver, Colorado. Prior to August 2018, methodology to identify long-term care facility (LTCF) residency among reported GAS cases was accomplished by reviewing addresses reported electronically, and identification of postsurgical cases and outbreaks relied on reporting by healthcare facilities. We evaluated whether the use of a health information exchange (HIE) to identify healthcare exposures improved our ability to detect and rapidly respond to these events. Methods: In August 2018, we implemented a review of health records available in the HIE accessible by the Colorado Department of Public Health and Environment for all incoming reports of GAS for selected healthcare exposures: LTCF residency, surgery, delivery, wound care, and other relevant exposures. We defined an LTCF-related case as GAS in a current or recent resident (ie, in the 14 days prior to the positive culture) of an LTCF. Postpartum and postsurgical cases were defined as GAS isolated from a sterile site or wound during the inpatient stay or within 7 days of discharge following a delivery or surgical procedure. Outbreaks in each of these settings were defined as 2 or more cases within a 3-month period. We compared the number of cases and outbreaks identified in each category during a 1-year period before and after implementation of the use of the HIE in the case ascertainment process. Results: During August 2017 through July 2018, prior to implementation of the HIE process, we detected 45 LTCF cases and conducted outbreak investigations in 9 facilities. Moreover, 1 postsurgical case and 1 postpartum outbreak were reported by healthcare facilities; none were detected via surveillance. During August 2018 through July 2019, after the implementation of HIE process, we identified 70 LTCF cases and conducted outbreak investigations in 13 LTCFs. We detected 5 postsurgical cases and 3 postpartum cases, which resulted in 2 outbreak investigations. Conclusions: Enhanced GAS surveillance through use of a HIE resulted in detection of more healthcare-associated GAS infections and outbreaks. Timely identification of healthcare-associated GAS infections can allow for prompt response to outbreaks and promotion of proper infection control practices to prevent further cases. Jurisdictions in which GAS is a reportable condition should consider the use of HIEs as part of routine surveillance to identify GAS outbreaks in high-risk settings. HIEs should be made available to public health agencies for case ascertainment and outbreak identification.Funding: NoneDisclosures: None

The Incidence, Characteristics, and Outcomes of Community and Hospital-Associated S. aureus Disease in Fulton County, Georgia

Background: Due to reliance on hospital discharge data for case identification, the burden of noninvasive and community-acquired S. aureus disease is often underestimated. To determine the full burden of S. aureus infections, we utilized population-based surveillance in a large urban county. Methods: The Georgia Emerging Infections Program (GA EIP) conducted CDC-funded, population-based surveillance by finding cases of S. aureus infections in 8 counties around Atlanta in 2017. Cases were residents with S. aureus isolated from either a normally sterile site in a 30-day period (invasive cases) or another site in a 14-day period (noninvasive cases). Medical records (all invasive and 1:4 sample of noninvasive cases) among Fulton County residents were abstracted for clinical, treatment, and outcome data. Cases treated were mapped to standard therapeutic site codes. Noninvasive specimens were reviewed and attributed to an invasive case if both occurred within 2 weeks. Incidence rates were calculated using 2017 census population and using a weight-adjusted cohort to account for sampling. Results: In total, 1,186 noninvasive (1:4 sample) and 529 invasive cases of S. aureus in Fulton county were reviewed. Only 35 of 1,186 (2.9%) noninvasive cases were temporally linked to invasive cases, resulting in 5,133 cases after extrapolation (529 invasive, 4,604 noninvasive). All invasive cases and 3,776 of 4,604 noninvasive cases (82%) were treated (4,305 total). Treatment was highest in skin (90%) and abscess (97%), lowest in urine (62%) and sputum (60%), and consisted of antibacterial agents alone (65%) or in addition to drainage procedures (35%). Overall, 41% of all cases were hospitalized, 12% required ICU admission, and 2.7% died, almost exclusively with bloodstream and pulmonary infections. Attribution of noninvasive infection was most often outside healthcare settings (87%); only 341 (7.9%) were hospital-onset cases; however, 34% of cases had had healthcare exposure in the preceding year, most often inpatient hospitalization (75%) or recent surgery (35%). Estimated countywide incidence was 414 per 100,000 (130 for MRSA and 284 for MSSA), invasive infection was 50 per 100,000. Among treated cases, 57% were SSTI, and the proportion of cases caused by MRSA was ~33% but varied slightly by therapeutic site (Fig. 1). Conclusions: The incidence of treated S. aureus infection in our large urban county is estimated to be 414 per 100,000 persons, which exceeds previously estimated rates based on hospital discharge data. Only 12% of treated infections were invasive, and <1 in 10 were hospital onset. Also, two-thirds of treated disease cases were MSSA; most were SSTIs.Funding: Proprietary Organization: Pfizer.Disclosures: Scott Fridkin, consulting fee - vaccine industry (spouse).

Carbapenemase Production and Mortality Risk Among Carbapenem-Resistant Enterobacteriaceae Cases in Tennessee, United States

Background: Carbapenem-resistant Enterobacteriaceae (CRE) are an urgent public health threat associated with poor patient outcomes. CRE that produce carbapenemase (CP-CRE) are of particular concern because the mechanism-conferring genes in plasmids can be transferred to other bacteria. CRE are reportable in Tennessee (TN); isolate submission is required for CP production and resistance mechanism testing. We aimed to compare patient characteristics and outcomes between CP-CRE and non–CP-CRE patients to guide potential public health interventions. Methods: A retrospective cohort study to compare 30-day mortality, and clinical characteristics of CP-CRE to non–CP-CRE patients was conducted. Laboratory data were gathered from CRE isolates of Tennessee residents from July 1, 2015, to June 30, 2018. The most recent Council of State and Territorial Epidemiologists CRE and CP-CRE case definition was used to confirm and classify cases. Healthcare exposures within 1 year prior to onset, demographic characteristics, and clinical characteristics were obtained by linking surveillance data with the inpatient and outpatient Tennessee hospital discharge data. Cases were also matched with Tennessee vital statistics data to determine all-cause 30-day mortality from the event date. We evaluated risk ratios of 30-day mortality with a multivariable regression model. Results: Among 1,034 CRE cases that had at least 1 isolate submitted to public health, 445 (43.0%) were CP-CRE and 589 (57.0%) were non–CP-CRE. Among CP-CRE isolates, the blaKPC gene was found in 434 (98.9%). CP-CRE cases were more likely to have isolates from normally sterile sites, to have an organism with elevated resistance to meropenem (minimum inhibitory concentration, >16 µg/mL), to have prior admission to a long-term acute-care hospital, and to live in a nursing home (all P < .001). Also, 77 CP-CRE cases (17.3%) and 56 non–CP-CRE cases (9.6%) died within 30 days of infection onset. The risk of 30-day mortality was 57% higher for CP-CRE (adjusted risk ratio, 1.57; 95% CI:, 1.10–2.23) compared to non–CP-CRE patients after adjusting for comorbidities, nursing home residence, and prior healthcare exposures. Conclusions: CP-CRE cases had poorer outcomes than non–CP-CRE cases. This may be related in part to a higher proportion of sterile site infections among CP-CRE cases; our study was underpowered to analyze this subpopulation of sterile site cases. We plan to continue monitoring and performing analyses as mortality and hospital discharge data from more recent years become available and as more cases accumulate.Funding: NoneDisclosures: None

Antimicrobial Nonsusceptibility Among Invasive MRSA USA300 Strains by Healthcare Exposure, Three Sites, 2005–2016

Background: Incidence of community-associated (CA) and healthcare-associated, community-onset (HACO) USA300 methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections has remained unchanged in recent years. Traditionally considered a CA strain, USA300 is increasingly associated with healthcare settings. We examined whether antimicrobial nonsusceptibility among USA300 strains could distinguish epidemiologic class (community vs hospital), and whether divergences in susceptibility were occurring over time. Methods: We used data on invasive MRSA infections from active, population, and laboratory-based surveillance during 2005–2016 from 11 counties in 3 states. Invasive cases were defined as MRSA isolation from a normally sterile site in a surveillance area resident. Cases were considered hospital-onset (HO) if the culture was obtained >3 days after hospitalization and HACO if ≥1 of the following risk factors was present: hospitalization, surgery, dialysis, or residence in a long-term care facility in the past year; or central vascular catheter ≤2 days before culture. Otherwise, cases were considered CA. Sites submitted a convenience sample of clinical MRSA isolates for molecular typing and antimicrobial susceptibility testing. Molecular typing was performed by pulsed-field gel electrophoresis until 2008, when typing was inferred using a validated algorithm based on molecular characteristics. Reference broth microdilution was performed for 8 antimicrobials and interpreted based on CLSI interpretive criteria. We compared USA300 nonsusceptibility for HO and CA isolates. For antimicrobials with >5% nonsusceptibility and for which HO isolates had greater nonsusceptibility than CA isolates, we compared nonsusceptibility for HACO and CA and analyzed annual trends in nonsusceptibility within each epidemiologic class (ie, CA, HACO, and HO) using linear regression. Results: Of 17,947 MRSA cases during 2005–2016, isolates were available for 6,685 (37%), and 2,120 were USA300 (34% CA, 52% HACO, 14% HO). HO isolates had more nonsusceptibility than CA isolates to gentamicin (2.2% vs 0.6%; P = .03), levofloxacin (47.8% vs 39.7%; P = .02), rifampin (3.7 vs 1.1%; P = .01), and trimethoprim-sulfamethoxazole (3.4% vs 0.6%; P = .04). HACO isolates also had more nonsusceptibility than CA isolates to levofloxacin (50.9% vs 39.7%; P < .01). Levofloxacin nonsusceptibility increased during 2005–2016 for HACO and CA isolates (P < .01), but not among HO isolates (P = .36) (Fig. 1). Conclusions: Overall, nonsusceptibility across drugs cannot distinguish USA300 isolates causing HO versus CA disease. Although HO isolates had higher levofloxacin nonsusceptibility than CA and HACO isolates early on, USA300 MRSA HACO isolates now have levofloxacin nonsusceptibility most similar to that of HO isolates. Further study could help to explore whether increases in fluoroquinolone nonsusceptibility among CA and HACO cases may be contributing to the persistence of USA300 strains.Disclosures: NoneFunding: None

Genomic analysis of Clostridioides difficile in two regions reveals a diversity of strains and limited transmission

Background: The epidemic NAP1/027 Clostridioides difficile strain (MLST1, ST1) that emerged in the mid-2000 is on the decline. The current distribution of C. difficile strain types and their transmission dynamics are poorly defined. We performed whole-genome sequencing (WGS) of C. difficile isolates in 2 regions to identify the predominant multilocus sequence types (MLSTs) in community- and healthcare-associated cases and potential transmission between cases using whole-genome single-nucleotide polymorphism (SNP) analysis. Methods: Isolates were collected through the CDC Emerging Infections Program population-based surveillance for C. difficile infections (CDI) for 3 months between 2016 and 2017 in 5 Minnesota counties and 1 New York county. Isolates were limited to incident cases (CDI in a county resident with no positive C. difficile test in the preceding 8 weeks). Cases were classified as healthcare associated (HA-CDI) or community associated (CA-CDI) based on healthcare exposures as previously described. WGS was performed on an Illumina Miseq. The CFSAN (FDA) pipeline was used to compute whole-genome SNPs, SPAdes was used for assembly, and MLST was assigned according to www.pubmlst.org. Results: Of 431 isolates, 269 originated from New York and 162 from Minnesota; 203 cases were classified as CA-CDI and 221 as HA-CDI. The proportion of CA-CDI cases was higher in Minnesota than in New York: 62% vs 38%. The predominant MLSTs across both sites were ST42 (9%), ST8 (8%), and ST2 (8%). MLSTs more frequently encountered in HA-CDI than CA-CDI included ST1 (note that this ST includes PCR Ribotype 027; 76% HA-CDI), ST53 (84% HA-CDI), and ST43 (80% HA-CDI). In contrast, ST110 (63% CA-CDI) and ST3 (67% CA-CDI) were more commonly isolated from CA-CDI cases. ST1 accounted for 7.6% of circulating strains and was more common in New York than Minnesota (10% vs 3%) and was concentrated among New York HA-CDI cases. Also, 412 isolates (1 per patient) were included in the final whole-genome SNP analysis. Of these, only 12 pairs were separated by 0–3 SNPs, indicating potential transmission, and most involved HA-CDI cases. ST1, ST17, and ST46 accounted for 8 of 12 pairs, with ST17 and ST46 potentially forming small clusters. Conclusions: This analysis provides a snapshot of the current genomic epidemiology of C. difficile across 2 geographically and epidemiologically distinct regions of the United States and supports other studies suggesting that the role of direct transmission in the spread of CDI may be limited.Funding: NoneDisclosures: None

Hepatitis C Virus Transmission at a Long-Term Care Facility (LTCF) Providing Hemodialysis Services—Georgia, United States, 2019

Background: Hepatitis C virus (HCV) transmission at outpatient hemodialysis clinics is well documented, but little is known about HCV transmission risks in long-term care facilities (LTCFs) providing hemodialysis services. LTCFs can provide onsite hemodialysis for residents by contracting with a licensed hemodialysis clinic to either provide its staff to the LTCF or to train LTCF staff as caregivers. In August 2019, the Georgia Department of Public Health (DPH) was notified about an HCV seroconversion in patient A at a LTCF providing onsite hemodialysis. Methods: Three residents (including patient A) were receiving hemodialysis at the LTCF in August 2019; patients B and C had chronic HCV infection upon admission. Records were reviewed for medical history, behavioral risk factors, and healthcare exposures. We conducted onsite infection control assessments and interviewed staff. Serum specimens were collected for all 3 patients in August 2019 and HCV tested for genetic similarity using Global Hepatitis Outbreak Surveillance Technology (GHOST). Results: The facility reported initiating onsite hemodialysis in November 2018; facility staff were trained by a dialysis provider. Patient A, admitted in September 2018, was anti-HCV negative in June 2019 and both anti-HCV and HCV RNA positive in July 2019. Patient B was admitted in December 2018, discharged for 1 month in May 2019, and then readmitted. Patients A and B reported previous injection drug use, and they were not observed by staff to use during their stay and had limited mobility. Patient A was wheelchair confined and B was bed confined. Patient C was admitted in May 2019. HCV samples from patients A and B both had HCV genotype 1b and demonstrated 100% genetic relatedness, indicating that patient B was the likely source. Patient C had HCV genotype 1a. Hemodialysis was provided to residents simultaneously in a converted resident room with 4 hemodialysis stations, and the LTCF operated 2 shifts, 3 times per week. We observed multiple infection control gaps, such as preparation of IV medications and inadequate disinfection in the shared dialysis treatment area. Recommendations addressing gaps were issued, and a follow-up site visit was conducted to validate implementation. With the exception of May 2019, patients A and B received hemodialysis on the same shift and days from December 2018 to September 2019. Conclusions: Phylogenetic and epidemiological results indicate HCV transmission likely occurred during hemodialysis services provided by the LTCF. As the provision of dialysis expands to nontraditional settings such as LTCFs, it is essential that proper infection control procedures and oversight are in place.Funding: NoneDisclosures: None

Characterization of Ceftazidime-Avibactam-Resistant Carbapenem-Resistant Enterobacteriaceae, United States, 2015–2017

Background: Carbapenem-resistant Enterobacteriaceae (CRE) are a major public health problem. Ceftazidime-avibactam (CZA) is a treatment option for CRE approved in 2015; however, it does not have activity against isolates with metallo-β-lactamases (MBLs). Emerging resistance to CZA is a cause for concern. Our objective was to describe the microbiologic and epidemiologic characteristics of CZA-resistant (CZA-R) CRE. Methods: From 2015 to 2017, 9 states participated in laboratory- and population-based surveillance for carbapenem-resistant Escherichia coli, Klebsiella pneumoniae, K. oxytoca, K. aerogenes, and Enterobacter cloacae complex isolates from a normally sterile site or urine. A convenience sample of isolates from this surveillance were sent to the CDC for antimicrobial susceptibility testing (AST) using reference broth microdilution (BMD) including an MBL screen, species confirmation with MALDI-TOF, and real-time PCR to detect blaKPC, blaNDM, and blaOXA-48–like genes. Additional AST by BMD was performed on CZA-R isolates using meropenem-vaborbactam (MEV), imipenem-relebactam (IMR), plazomicin (PLZ), and eravacycline (ERV). Epidemiologic data were obtained from a medical record review. Community-associated cases were defined as having no healthcare exposures in the year prior to culture, no devices in place 2 days prior to culture, and culture collected before calendar day 3 after hospital admission. Data were analyzed in 3 groups: CRE that were CZA-susceptible (CZA-S), CZA-R that were due to blaNDM, and CZA-R without blaNDM. Results: Among 606 confirmed CRE tested with CZA, 33 (5.4%) were CZA-R. Of the CZA-R isolates, 16 (48.5%) harbored a blaNDM gene, of which 2 coharbored blaNDM and blaOXA-48-like genes; 9 (27.3%) harbored only a blaKPC gene. Of the 17 CZA-R isolates without blaNDM, all were MBL screen negative. CZA-R due to blaNDM were more frequently community-associated (43.8%) than CZA-S or CZA-R without blaNDM (11.0% and 5.9%, respectively); a higher percentage of CZA-R cases due to blaNDM also had recent international travel (25%) compared to the other groups (1.8% and 5.9%, respectively). CZA-R without blaNDM were more susceptible to MEV (76%), IMR (71%), PLZ (88%), and ERV (65%) compared to CZA-R due to blaNDM (19%, 6%, 56%, and 44%, respectively). Conclusions: The emergence of CZA-R isolates without blaNDM are concerning; however, these isolates are more susceptible to newer antimicrobials than those with blaNDM. In addition to high rates of resistance to newer antimicrobials, isolates with blaNDM are more frequently community-associated than other CRE. This underscores the need for more aggressive measures to stop the spread of CRE.Funding: NoneDisclosures: None

Clinical and Genetic Characteristics of Extended-Spectrum Beta-Lactamase–Producing Enterobacteriaceae Among Canadian Children

Background: Infections with extended-spectrum β-lactamase–producing Enterobacteriaceae (ESBL-E) in nonoutbreak settings have not demonstrated the presence of dominant strains. Our objective was to determine the incidence, clinical characteristics, and genetic characteristics of ESBL-E infections among a group of Canadian children. Methods: From 2012 through 2017, patients aged ≤18 years with first-episode ESBL-E infections who presented at a pediatric center were reviewed. All clinical isolates were phenotypically identified in the laboratory as ESBL-producers. Demographic and clinical data were collected, including comorbid conditions, presence of devices, and previous antibacterial exposure. Community-associated infection was defined as a positive culture from a sterile site within the first 48 hours of hospital admission and no healthcare exposure during the preceding year. Isolates were sent to the Public Health Ontario Laboratory for whole-genome sequencing. Multilocus sequence typing was used to determine clonal relationship. Results: During the study period, 102 patients were identified with first-episode ESBL-E infection, and the proportion of ESBL-E isolates among all clinical isolates of E. coli and Klebsiella spp increased from 0.6% to 2.6% between 2012 and 2017, respectively (P = .001). The median age was 1 year (interquartile range, 0.8–5 years). Women comprised 66% of cases. No comorbid conditions were noted among 58 patients (57%), and 24% had previous antibiotic exposure, most frequently a cephalosporin (16%). ESBL-E was most frequently isolated in the urine (91%) and least frequently in the blood (2.2%) and was predominantly Escherichia coli (90%). Infection was most frequently diagnosed in the outpatient setting (61%); there were 11 healthcare-associated infections. Whole-genome sequencing of ESBL-E isolates revealed predominance of blaCTX-M-15 (63 isolates, 62%) and blaCTX-M-27 (16%) genes, and sequence type (ST) 131 (41%). Mutations conferring fluoroquinolone nonsusceptibility were noted among 62 isolates (61%), most frequently associated with ST131 (38 of 62 isolates, 61%) and among all 5 isolates with ST1193, an emerging multidrug-resistant E. coli clone. In addition, 15 patients had recurrence of ESBL-E infection at median of 113 days (IQR, 26–208); blaCTX-M-27 was found in 33% of recurrent infections compared to 12% of primary infections (P = 0.045). Conclusions: This study is the first in Canada to provide whole-genome sequencing data regarding ESBL-E in a pediatric population. The gene blaCTX-M-15 and ST131 clone were predominant. More than 60% of infections were community associated and demonstrated cross resistance to fluoroquinolones. With 76% of infections in antibiotic-naïve children, ESBL-E is a public health concern, and a One Health approach is critical to understanding the epidemiology and curbing the spread of multidrug-resistant Enterobacteriaceae.Funding: NoneDisclosures: None

Molecular Epidemiology of Community-Onset (CO), Community-Onset Healthcare-Associated (CO-HA) and Hospital-Onset (HO) Methicillin-Resistant Staphylococcus aureus (MRSA)

Background: Previous work suggests an intermingling of community and hospital transmission networks driving the MRSA epidemic, but how those with CO-HA infections fit into the network remains unclear. We integrated epidemiologic data and whole-genome sequencing (WGS) from existing MRSA clinical isolates to determine whether there were distinguishable features of CO-HA MRSA infections that could guide interventions. Methods: We examined 955 existing clinical MRSA isolates from 2011 to 2013 from patients at Cook County Health, the major public healthcare network in Chicago, Illinois. We performed electronic and manual chart review to ascertain community (eg, illicit drug use, incarceration history) and healthcare exposures and comorbidities. WGS was performed on all sequences, and sequences were typed with multilocus sequence typing (MLST). We assessed the distribution of epidemiological factors and sequence type (ST) across onset type. Results: Infections were more frequent in males (70%); 61% of individuals with infection were African American and 21% were Hispanic. Overall, wound infections were the most common (81%) followed by blood (7%) and respiratory (6%). 82% of infections were ST8 (most USA300), 8% were ST5 (USA100) and 10% were other STs (Fig. 1a). Using standard epidemiologic definitions, we identified 523 CO, 295 CO-HA, and 137 HO infections. USA300 infections were common across CO, CO-HA, and HO categories, whereas USA100 was more frequently observed among CO-HA and HO. Current illicit drug use and history of incarceration—factors typically associated with CO-MRSA—were observed among both CO-HA and HO infections. 38% of CO-HA and 36% of HO had a history of MRSA infection or nasal colonization in the prior 6 months. As expected, 73% of CO-HA had a history of recent hospitalization, but this was also true for 44% of HO cases; points for intervention for both groups, especially CO-HA patients, include outpatient, inpatient, and ER care. Diabetes was common across categories, and HIV was more commonly observed among CO-HA cases (Fig. 1b). Conclusions: We characterized the genomic and epidemiologic features of CO-HA MRSA infections relative to CO and HO. By MLST and epidemiological analysis, CO-HA infections share similarities to both CO and HO. Although USA300 infections were the most common strain type, our findings highlight the need for WGS to discern relationships between individuals to understand the intermixing of healthcare and community networks for CO-HA infections. Higher resolution genomic analysis may help guide whether interventions need to be at hospital discharge or in the community to have the most impact on decreasing CO-HA MRSA infections.Funding: Funding: from CDC Broad Agency Announcement: Genomic Epidemiology of Community-Onset Invasive USA300 MRSA Infections; Contract ID: 75D30118C02923Disclosures: None

Low Carriage Rates of Multidrug-Resistant Organisms in Prospective Stool Donors in a Large Fecal Microbiota Transplantation (FMT) Stool Bank

Background: Fecal microbiota transplantation (FMT) has emerged as standard of care for Clostridioides difficile not responsive to antibiotic therapy. Rigorous screening of healthy donors is critical to patient safety. As part of routine donor evaluation for FMT, multidrug-resistant organism (MDRO) screening is performed to assess the presence of extended-spectrum β-lactamase–producing organisms (ESBLs), vancomycin-resistant enterococci (VRE), carbapenem-resistant Enterobacteriaceae (CRE), and methicillin-resistant Staphylococcus aureus (MRSA). Carriage rates of these organisms in a healthy, low-risk population are largely unknown. We report MDRO carriage rates among individuals screened for a stool donation program at a large-scale FMT stool bank. Methods: Individuals were screened at a nonprofit stool bank (OpenBiome, Cambridge, MA). Potential donors underwent in-person clinical assessment, including MDRO risk factors (eg, travel, occupation, healthcare exposure). If they met the clinical assessment criteria, laboratory testing, including MDROs, was performed. Once enrolled in the donor program, donors underwent repeated clinical and laboratory screening at 60-day intervals, with intermittent health checks throughout the donation period. Stool samples provided at 60-day intervals were screened for MDROs (ie, ESBL, CRE, VRE), and nasal swabs for MRSA were tested using culture-based methods. All stool samples tested for MDROs from prospective and enrolled donors were included. Results: Between February 2017 and July 2019, 247 individuals were screened for MDROs. Overall, 11 samples (0.04%) tested positive for ESBL, MRSA, or VRE. No CRE carriers were identified. Also, 2 individuals tested positive twice for ESBL, resulting in 13 of 1,688 (0.77%) positive screens. International travel in the previous 12 months was reported by 6 of 11 MDRO carriers. Occupations typically associated with MDROs were not observed in carriers. Most of the MDRO-positive donors were students; however, students make up the majority of the stool donor cohort. Conclusions: This study is the first to report background MDRO carriage rates in a population of otherwise healthy FMT stool donors. Although rare, MDROs were detected and should be part of standard guidelines for FMT donor screening. Most subjects testing positive for MDROs had defined risk factors associated with MDRO carriage, including international travel or exposure to healthcare environments. However, occupational exposure was not a factor associated with carriage in this study. Standardized donor screening guidelines for FMT are urgently needed to ensure that MDROs and risk factors for MDRO carriage are routinely screened for by all FMT providers. Stool banks present a unique public health opportunity to evaluate the background carriage rate of MDROs in healthy populations.Funding: NoneDisclosures: None