Prior Healthcare Exposure Research Articles

Antibiotic susceptibility of pathogens isolated in respiratory tract samples of recently hospitalized patients.

Community-acquired lower respiratory tract infections (CA-LRTIs) treatment is largely empirical as microbiologic testing is rarely performed. Here, we provide microbiologic data of severe CA-LRTI cases requiring hospitalization. We aim to describe the distribution and susceptibility patterns of pathogens causing severe CA-LRTI. We analyzed respiratory samples from recently admitted patients with CA-LRTIs to assess pathogen distribution and antibiotic susceptibility patterns. We divided patients into three groups: CA-LRTI and no prior healthcare exposure, CA-LRTI with healthcare exposure, and patients diagnosed with LRTI 48 to 7 days of hospital admission. In a sub-cohort, we assessed the bacteria's susceptibility to cefditoren. A total of 1,395, 2,212, and 2,760 samples were included in the three study groups. Gram-negative bacteria were the most common bacteria isolated. Streptococcus pneumoniae was over-represented in patients admitted to the intensive care unit (ICU) in the first two study groups, and was fully susceptible to penicillin in only ~50% of cases, and to fluoroquinolones and third-generation cephalosporins including cefditoren in >95% of cases. Susceptibility of Gram-negative bacteria to penicillins and to second-generation cephalosporins was lower than 50%. Age, admission to an ICU or surgical department, healthcare-associated infections, and infections with Gram-negative bacteria, Staphylococcus aureus, and Stenotrophomonas/Acinetobacter baumannii were associated with increased mortality. These results highlight pathogen diversity and concerning antibiotic susceptibility patterns in LRTI. These findings emphasize the importance of improving diagnostics and addressing antibiotic resistance in the effective management of LRTI.IMPORTANCEThis survey aims to describe the microbiologic aspects of community-acquired lower respiratory tract infections (CA-LRTI) in a large cohort of patients recently admitted to hospital. In a small sub-study, we assessed antibiotic susceptibility to cefditoren, an oral third-generation cephalosporin not used in Israel. By analyzing specimens from recently admitted patients with CA-LRTI, we aim to provide physicians with the relevant microbiologic data of the more severe CA-LRTI cases, i.e., those that resulted in hospital admission. Such microbiological data would provide primary care and emergency room physicians with additional insights as to the causative agents of severe CA-LRTI.

P-313. Trends in Invasive Staphylococcus aureus infections in Monroe County, NY, 2016-2023

Abstract Background Since the COVID-19 pandemic, increases in healthcare-associated invasive methicillin-resistant S. aureus (MRSA) infections were observed. Limited data exist for invasive methicillin-sensitive S. aureus (MSSA) infections. We identified trends in community and healthcare associated invasive S. aureus (iSA) infections during 2016-2023.Figure 1.Incidence of iSA infections by resistance-type, Monroe County, NY, 2016-2023. Methods Active, population-based surveillance data for iSA was collected as part of the CDC Emerging Infections Program. A case was defined as a resident of Monroe County, NY with S. aureus isolated from a normally sterile site. Cases were classified as hospital onset (HO) if the culture was obtained >3 days after hospitalization, healthcare-associated community-onset (HACO) if the culture was obtained in an outpatient setting or < 3 days after hospitalization in a patient with ≥1 prior major healthcare exposures, or otherwise community-associated (CA); incidence was calculated for each epidemiologic classification.Figure 2.Incidence of iSA infections by epidemiologic classification, Monroe County, NY, 2016-2023. Results A total 4,440 iSA cases were identified during 2016-2023; 3,512 had S. aureus isolated from blood and 942 were from other sterile sites. iSA incidence increased from 66.5 (per 100,000 population) in 2016 to a peak of 87.9 in 2023 (Figure 1). HACO comprised >50% cases and incidence mirrored the pattern of overall rates, rising from 33.8 in 2016 to 48.9 in 2023 (Figure 2). HO incidence doubled, rising from 9 in 2016 to 18.2 in 2023; CA incidence remained stable. MSSA incidence was approximately twice the rate of MRSA for each year. Incidence of MSSA rapidly increased from 2020 to 2021 (42.7 to 57.6) with increases in all epidemiologic classes (Figure 3). MRSA rose the following year (23.8 to 31.1) with a decline in CA cases; HO increased by 59% and HACO increased by 33%.Figure 3.Comparison of epidemiologic classification between MRSA vs. MSSA cases, Monroe County, NY, 2016-2023. Conclusion Our study highlights an increase in iSA infections since 2016, predominantly driven by HACO cases. MSSA infections surpassed MRSA infections throughout, with both experiencing sustained increases since COVID-19 emerged. These findings emphasize the importance of continued surveillance and targeted interventions to address the growing burden of iSA infections, particularly those associated with healthcare. Disclosures All Authors: No reported disclosures

P-1359. Epidemiology of Carbapenem Resistant Enterobacterales in Monroe County, NY 2016-2023

Abstract Background Carbapenem-resistant Enterobacterales (CRE) infections pose an urgent threat due to the limited treatment options and the potential for resistance spread among carbapenemase producing (CP) CRE strains. Methods We conducted active population-based surveillance for select Enterobacterales species resistant to ≥ 1 carbapenem from a normally sterile site or urine in Monroe County, NY as part of the CDC Emerging Infections Program. Epidemiologic data were collected through medical record abstraction. Cases were classified as hospital onset (HO) if they occurred 72 hours after hospital admission, healthcare-associated community-onset (HACO) cases if they had a prior healthcare risk factor, or community associated (CA). CRE isolates were tested at CDC or Northeast Antimicrobial Resistance Laboratory Network. Results From 2016-2023, CRE incidence increased 135% from 8.8 to 20.7 per 100,000 population with 895 incident CRE cases identified in 745 unique patients. Patients were mostly non-Hispanic (89.2%), White (82.1%) and female (67.8%). Urine was the most common source (92.7%). 58.1% of cases were HACO, 28.6% CA and 13.2% HO. Urinary tract abnormalities (58%) and recurrent UTIs (32.6%) were prevalent. Prior healthcare exposures including hospitalization (57.2%), surgery (28.5%), and skilled nursing home stay (22.1%) were common in healthcare associated cases. Few (2%) had a history of international travel. Hospital onset cases were more likely to have CRE isolated from blood (21.2%), require ICU admission (33.1%), and die within 90 days of their infection (34.4%). 272 CRE isolates underwent carbapenemase testing, of those, 78 (28.7%) were CP-CRE: 71.1% blaKPC, 19.3% blaNDM, and 9.6% blaOXA48 with documented emergence of blaNDM CP in 2021. Only 6 (9.5%) of CA isolates were CP-CRE compared to 18 (40%) of HO, and 54 (33.1%) of HACO. Conclusion The incidence of CRE in Monroe County, NY has significantly increased since 2016 with documented emergence of blaNDM-producing strains. The high proportion of healthcare-associated CRE cases, particularly CP-CRE, underscores the need for enhanced infection control measures and ongoing surveillance. Further investigation is needed into the risk of CP-CRE in CA cases. Disclosures All Authors: No reported disclosures

Application of a Model Using Prior Healthcare Information to Predict Multidrug-Resistant Organism (MDRO) Carriage

Background: Early identification of patients colonized with MDROs can help healthcare facilities improve infection control and treatment. We evaluated whether a model previously validated to predict carbapenem-resistant Enterobacterales (CRE) carriage on hospital admission (area under the curve [AUC]=0.86, Lin et al. OFID 2019) would generalize to predict a patient’s likelihood of CRE and non-CRE MDRO colonization at the time of medical intensive care unit (MICU) admission. Methods: We analyzed data collected previously in a retrospective observational cohort study of patients admitted to Rush University Medical Center’s MICU from 1/2017-1/2018 and screened within the first two days for rectal MDRO colonization. Organisms of interest included CRE, carbapenem-resistant Pseudomonas aeruginosa (CRPA), vancomycin-resistant enterococci (VRE), and third-generation cephalosporin-resistant Enterobacterales (3GCR-E). Methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization at admission was determined by routine clinical screening. Each patient’s first MICU admission during the study period was linked to Illinois’ hospital discharge database and assigned a CRE colonization risk probability using the existing model. Model covariates were age, and during the prior 365 days, number of short-term acute care hospitalizations (STACH) and mean STACH length of stay, number of long-term acute care hospitalizations (LTACH) and mean LTACH length of stay, prior hospital admission with an ICD-10 diagnosis code indicating bacterial infection, and current admission to LTACH. Predictive value of the model was evaluated by receiver operating characteristic (ROC) curves. Results: We analyzed 1237 MICU admissions. MDRO admission prevalence is shown in the Table. The model performed well to predict carriage of healthcare-associated MDROs, including CRE, CRPA, composite CR-MDROs (CRE & CRPA), and VRE. However, the model performed poorly for MDROs with known community reservoirs, including 3GCR-E and MRSA (Table). In general, MDRO admission prevalence increased in parallel with predicted CRE colonization risk (Figure). The number needed to screen (NNS) to detect one healthcare-associated MDRO carrier was inversely related to the CRE colonization risk score. For example, NNS in the total cohort compared to those with CRE risk score of >0.5% was: CRE 111 vs 32 patients, CRPA 333 vs 42 patients, composite CR-MDRO 83 vs 18 patients, and VRE 12 vs 4 patients. However, higher CRE risk score cutoff was inversely related to screening sensitivity. Conclusion: A prediction model using prior healthcare exposure information successfully discriminated patients likely to harbor healthcare-associated MDROs upon MICU admission. Prediction scores generated by a public-health accessible database could be used to target screening/isolation or enact protective measures for high-risk patients.

Perinatal colonization with extended-spectrum beta-lactamase-producing and carbapenem-resistant Gram-negative bacteria: a hospital-based cohort study

BackgroundAntimicrobial resistance (AMR) is a growing global health threat that contributes to substantial neonatal mortality. Bangladesh has reported some of the highest rates of AMR among bacteria causing neonatal sepsis. As AMR colonization among newborns can predispose to infection with these bacteria, we aimed to characterize the frequency of and risk factors for colonization of mothers and newborns during hospitalization for delivery.MethodsWe enrolled pregnant women presenting for delivery to a tertiary care hospital in Faridpur, Bangladesh. We collected vaginal and rectal swabs from mothers pre- and post-delivery, rectal swabs from newborns, and swabs from the hospital environment. Swabs were plated on agars selective for extended-spectrum-beta-lactamase producing bacteria (ESBL-PB) and carbapenem-resistant bacteria (CRB). We performed logistic regression to determine factors associated with ESBL-PB/CRB colonization.ResultsWe enrolled 177 women and their newborns during February-October 2020. Prior to delivery, 77% of mothers were colonized with ESBL-PB and 15% with CRB. 79% of women underwent cesarean deliveries (C-section). 98% of women received antibiotics. Following delivery, 98% of mothers and 89% of newborns were colonized with ESBL-PB and 89% of mothers and 72% of newborns with CRB. Of 290 environmental samples, 77% were positive for ESBL-PB and 69% for CRB. Maternal pre-delivery colonization was associated with hospitalization during pregnancy (RR for ESBL-PB 1.24, 95% CI 1.10–1.40; CRB 2.46, 95% CI 1.39–4.37). Maternal post-delivery and newborn colonization were associated with C-section (RR for maternal CRB 1.31, 95% CI 1.08–1.59; newborn ESBL-PB 1.34, 95% CI 1.09–1.64; newborn CRB 1.73, 95% CI 1.20–2.47).ConclusionsIn this study, we observed high rates of colonization with ESBL-PB/CRB among mothers and newborns, with pre-delivery colonization linked to prior healthcare exposure. Our results demonstrate this trend may be driven by intense use of antibiotics, frequent C-sections, and a contaminated hospital environment. These findings highlight that greater attention should be given to the use of perinatal antibiotics, improved surgical stewardship for C-sections, and infection prevention practices in healthcare settings to reduce the high prevalence of colonization with AMR organisms.

1933. Characteristics of Community-Associated Extended-Spectrum β-Lactamase Producing Enterobacterales Infections in Monroe County, NY, 2020-2021

Abstract Background Extended-spectrum β-lactamase–producing Enterobacterales (ESBL) have emerged as a serious multidrug resistant threat to the community. Epidemiologic data for community-associated (CA) ESBL infections are limited compared to that for healthcare-associated (HA) infections. We examined characteristics of CA ESBL cases over a two-year period and compared them to those of HA cases to guide prevention. Methods CA ESBL cases from 1/2020-12/2021 were identified via laboratory and population-based surveillance in Monroe County as part of the CDC Emerging Infections Program. Cases were defined as the first instance of positive culture in a county resident from a normally sterile site or urine of Escherichia coli, Klebsiella pneumoniae, or K. oxytoca resistant to ≥ 1 3rd-generation cephalosporin and nonresistant to carbapenems. Epidemiologic data were collected through medical record abstraction. Cases were classified as HA if they had prior healthcare exposures (e.g. hospitalization, surgery, chronic dialysis, indwelling devices, or external catheters) and CA if they did not. Case addresses were geocoded to the census tract level to obtain Social Vulnerability Index (SVI) percentiles. Chi-square analyses were conducted to quantify the difference in distribution of these characteristics between CA and HA cases. Results From 2020-2021, 1729 incident cases were identified; 854 (49%) were classified as CA. Compared to HA cases, CA cases were younger (median 59 vs. 70 years), more likely to be female (89.8% vs 65.3%), less likely to have a urinary tract abnormality (27.0% vs 56.8%) or underlying comorbidities (73.2 % vs 95.8%), and less likely to have received prior antibiotics (24.0% vs 55.1%). Interestingly, CA cases were more widely spread across SVI quartiles compared to HA cases; a higher proportion of HA cases resided in census tracts in the 3rd or 4th SVI quartiles (Table 1). Conclusion Patient-specific risk factors classically associated with HA ESBL are less commonly associated with CA ESBL in Monroe County. Community-based preventions may need to target different populations than hospital-based strategies. As ESBL incidence increases, continued surveillance to identify at-risk groups and explore the association of specific social determinants of health is necessary. Disclosures Rebecca Tsay, MPH, CDC: Grant/Research Support Ghinwa Dumyati, MD, Pfizer: Grant/Research Support

Comparison of Risk Stratification Approaches to Identify Patients with Clostridioides difficile Infection at Risk for Multidrug-Resistant Organism Gut Microbiota Colonization.

Multidrug-resistant organisms (MDRO) commonly colonize the gut microbiota of patients with Clostridioides difficile infection (CDI). This increases the likelihood of systemic infections with these MDROs. To help guide MDRO screening and/or empiric antibiotic therapy, we derived and compared predictive indices for MDRO gut colonization in patients with CDI. This was a multicenter, retrospective cohort study of adult patients with CDI from July 2017 to April 2018. Stool samples were screened for MDRO via growth and speciation on selective antibiotic media and confirmed using resistance gene polymerase chain reaction. Aregression-based risk score for MDRO colonization was constructed. Predictive performance via area under the receiver operating characteristic curve (aROC) of this index was compared with two other simplified risk stratification approaches: (1) prior healthcare exposure and/or high-CDI risk antibiotics; (2) number of prior high-CDI risk antibiotics. 50 (20.8%) of 240 included patients had MDRO colonization; 35 (14.6%) VRE, 18 (7.5%) MRSA, 2 (0.8%) CRE. Prior fluoroquinolone (aOR 2.404, 95%CI 1.095-5.279) and prior vancomycin (1.996, 95%CI 1.014-3.932) were independently associated with MDRO colonization while prior clindamycin (aOR 3.257, 95%CI 0.842-12.597) and healthcare exposure (aOR 2.138, 95%CI 0.964-4.740) were retained as explanatory variables. The regression-based risk score significantly predicted MDRO colonization (aROC 0.679, 95%CI 0.595-0.763), but was not significantly more predictive than prior healthcare exposure + prior antibiotics (aROC 0.646, 95%CI 0.565-0.727) or number of prior antibiotic exposures (aROC 0.642, 95%CI 0.554-0.730); P > 0.05 for both comparisons. A simplified approach using prior healthcare exposure and receipt of prior antibiotics known to increase CDI risk identified patients at risk for MDRO gut microbiome colonization as effectively as individual patient/antibiotic risk modeling.

Epidemiology of carbapenem-resistant and extended-spectrum beta-lactamase-producing Enterobacterales in US children, 2016–2020

Background: The Centers for Disease Control and Prevention’s Emerging Infections Program conducts active laboratory- and population-based surveillance for carbapenem-resistant Enterobacterales (CRE) and extended spectrum beta-lactamase-producing Enterobacterales (ESBL-E). To better understand the U.S. epidemiology of these organisms among children, we determined the incidence of pediatric CRE and ESBL-E cases and described their clinical characteristics. Methods: Surveillance was conducted among children <18 years of age for CRE from 2016–2020 in 10 sites, and for ESBL-E from 2019–2020 in 6 sites. Among catchment-area residents, an incident CRE case was defined as the first isolation of Escherichia coli, Enterobacter cloacae complex, Klebsiella aerogenes, K. oxytoca, or K. pneumoniae in a 30-day period resistant to ≥1 carbapenem from a normally sterile site or urine. An incident ESBL-E case was defined as the first isolation of E. coli, K. pneumoniae, or K. oxytoca in a 30-day period resistant to any third-generation cephalosporin and non-resistant to all carbapenems from a normally sterile site or urine. Case records were reviewed. Results: Among 159 CRE cases, 131 (82.9%) were isolated from urine and 19 (12.0%) from blood; median age was 5 years (IQR 1–10) and 94 (59.1%) were female. Combined CRE incidence rate per 100,000 population by year ranged from 0.47 to 0.87. Among 207 ESBL-E cases, 160 (94.7%) were isolated from urine and 6 (3.6%) from blood; median age was 6 years (IQR 2–15) and 165 (79.7%) were female. Annual ESBL incidence rate per 100,000 population was 26.5 in 2019 and 19.63 in 2020. Incidence rates of CRE and ESBL-E were >2-fold higher in infants (children <1 year) than other age groups. Among those with data available, CRE cases were more likely than ESBL-E cases to have underlying conditions (99/158 [62.7%] versus 59/169 [34.9%], P<0.0001), prior healthcare exposures (74/158 [46.8%] versus 38/169 [22.5%], P<0.0001), and be hospitalized for any reason around time of their culture collection (75/158 [47.5%] versus 38/169 [22.5%], P<0.0001); median duration of admission was 18 days [IQR 3–103] for CRE versus 10 days [IQR 4–43] for ESBL-E. Urinary tract infection was the most frequent infection for CRE (89/158 [56.3%]) and ESBL-E (125/169 [74.0%]) cases. Conclusion: CRE infections occurred less frequently than ESBL-infections in U.S. children but were more often associated with healthcare risk factors and hospitalization. Infants had highest incidence of CRE and ESBL-E. Continued surveillance, infection prevention and control efforts, and antibiotic stewardship outside and within pediatric care are neededDisclosure: None

Colonization with extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE) in hospitalized patients in Botswana

Background: The epidemiology of extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE) in hospitalized patients in low- and middle-income countries (LMICs) is poorly described. Although risk factors for ESCrE clinical infection have been studied, little is known of the epidemiology of ESCrE colonization. Identifying risk factors for ESCrE colonization, which can predispose to infection, is therefore critical to inform antibiotic resistance reduction strategies. Methods: This study was conducted in 3 hospitals located in 3 districts in Botswana. In each hospital, we conducted ongoing surveillance in sequential units hospitalwide. All participants had rectal swabs collected which were inoculated onto chromogenic media followed by confirmatory testing using MALDI-TOF MS and VITEK-2. Data were collected via interview and review of the inpatient medical record on demographics, comorbidities, antibiotic use, healthcare exposures, invasive procedures, travel, animal contact, and food consumption. Participants with ESCrE colonization (cases) were compared to noncolonized participants (controls) using bivariable and multivariable analyses to identify risk factors for ESCrE colonization. Results: Enrollment occurred from January 15, 2020, to September 4, 2020, and 469 participants were enrolled. The median age was 42 years (IQR, 31–58) and 320 (68.2%) were female. The median time from hospital admission to date of sampling was 5 days (IQR, 3–12). There were 179 cases and 290 controls (ie, 38.2% of participants were ESCrE colonized). Independent risk factors for ESCrE colonization were a greater number of days on antibiotic, recent healthcare exposure, and tending swine prior to hospitalization. (Table). Conclusions: ESCrE colonization among hospitalized patients was common and was associated with several exposures. Our results suggest prior healthcare exposure may be important in driving ESCrE. The strong link to recent antibiotic use highlights the potential role of antibiotic stewardship interventions for prevention. The association with tending swine suggests that animal husbandry practices may play a role in community exposures, resulting in colonization detected at the time of hospital admission. These findings will help to inform future studies assessing strategies to curb further emergence of hospital ESCrE in LMICs.Disclosures: None

Identifying patients at high risk for carbapenem-resistant Enterobacterales carriage upon admission to acute-care hospitals

Background: Prompt identification of patients colonized or infected with carbapenem-resistant Enterobacterales (CRE) upon admission can help ensure rapid initiation of infection prevention measures and may reduce intrafacility transmission of CRE. The Chicago CDC Prevention Epicenters Program previously created a CRE prediction model using state-wide public health data (doi: 10.1093/ofid/ofz483). We evaluated how well a similar model performed using data from a single academic healthcare system in Atlanta, Georgia, and we sought to determine whether including additional variables improved performance. Methods: We performed a case–control study using electronic medical record data. We defined cases as adult encounters to acute-care hospitals in a 4-hospital academic healthcare system from January 1, 2014, to December 31, 2021, with CRE identified from a clinical culture within the first 3 hospital days. Only the first qualifying encounter per patient was included. We frequency matched cases to control admissions (no CRE identified) from the same hospital and year. Using multivariable logistic regression, we compared 2 models. The “public health model” included 4 variables from the Chicago Epicenters model (age, number of hospitalizations in the prior 365 days, mean length of stay in hospitalizations in the prior 365 days, and hospital admission with an infection diagnosis in the prior 365 days). The “healthcare system model” added 4 additional variables (admission to the ICU in the prior 365 days, malignancy diagnosis, Elixhauser score and inpatient antibiotic days of therapy in the prior 365 days) to the public health model. We used billing codes to determine Elixhauser score, malignancy status, and recent infection diagnoses. We compared model performance using the area under the receiver operating curve (AUC). Results: We identified 105 cases and 441,460 controls (Table 1). CRE was most frequently identified in urine cultures (46%). All 4 variables included in the public health model and the 4 additional variables in the healthcare system model were all significantly associated with being a case in unadjusted analyses (Table 1). The AUC for the public health model was 0.76, and the AUC for the healthcare system model was 0.79 (Table 2; Fig. 1). In both models, a prior admission with an infection diagnosis was the most significant risk factor. Conclusions: A modified CRE prediction model developed using public health data and focused on prior healthcare exposures performed reasonably well when applied to a different academic healthcare system. The addition of variables accessible in large healthcare networks did not meaningfully improve model discrimination.Disclosures: None

Antimicrobial resistance and mortality following E. coli bacteremia

Global estimates suggest millions of deaths annually are associated with antimicrobial resistance (AMR) but these are generated from scarce data on the relative risk of death attributable to drug-resistant versus drug-sensitive infections. We examined all episodes of E.coli bloodstream infection in Ontario, Canada between 2017 and 2020, and measured 90 day mortality among those with resistant versus sensitive isolates for each of 8 commonly used antibiotic classes and a category of difficult to treat resistance (DTTR). We used multivariable logistic regression to calculate an adjusted odds of mortality associated with AMR, after accounting for patient demographics, comorbidities, and prior healthcare exposure. Among 14,548 eligible episodes of E.coli bloodstream infection, resistance was most common to aminopenicillins (46.8%), followed by first generation cephalosporins (38.8%), fluoroquinolones (26.5%), sulfonamides (24.1%), third generation cephalosporins (13.8%), aminoglycosides (11.7%), beta-lactam-beta-lactamase-inhibitors (9.1%) and carbapenems (0.2%). Only 18 (0.1%) episodes exhibited DTTR. For each antibiotic class, the unadjusted odds of mortality (OR) were higher among resistant isolates, but after accounting for patient characteristics the adjusted odds (aOR) of mortality were attenuated: aminopenicillins (OR 1.22, 95% CI 1.12-1.33; aOR 1.09, 95% CI 0.99-1.20), first generation cephalosporins (OR 1.24, 95% CI 1.14-1.35; aOR 1.07, 95% CI 0.97-1.18), third generation cephalosporins (OR 1.64, 95% CI 1.47-1.82; aOR 1.29, 95% CI 1.15-1.46), beta-lactam-beta-lactamase-inhibitors (OR 1.69, 95% CI 1.52-1.89, aOR 1.28, 95% CI 1.13-1.45), carbapenems (OR 3.11, 95% CI 1.52-6.34; aOR 2.06, 95% CI 0.91-4.66), sulfonamides (OR 1.19, 95% CI 1.07-1.31, aOR 1.06, 95% CI 0.95-1.18), fluoroquinolones (OR 1.49, 95% CI 1.36-1.64, aOR 1.16, 95% CI 1.05-1.29), aminoglycosides (OR 1.43, 95% CI 1.27-1.62; aOR 1.27, 95% CI 1.11-1.46), and DTTR (OR 3.71, 95% CI 1.46-9.41; aOR 2.58, 95% CI 0.87-7.66). AMR is associated with substantial increased mortality among patients with E.coli bloodstream infection, particularly for resistance to classes commonly used as empiric treatment. Surveillance for AMR-associated mortality should incorporate adjustment for patient characteristics and prior healthcare utilization. This work was supported by a project grant from CIHR (grant number 159503). This study was also supported by ICES, which is funded by an annual grant from Ontario Ministry of Health and Long-Term Care (MOHLTC).

86. Antibiotic-resistant gram-negative bacterial infections among persons with or without a prior positive test for SARS-CoV-2 in 10 U.S. sites, 2020

Abstract Background The Centers for Disease Control and Prevention’s Emerging Infections Program (EIP) conducts active laboratory- and population-based surveillance for carbapenem-resistant Enterobacterales (CRE), extended spectrum beta-lactamase-producing Enterobacterales (ESBL-E), and carbapenem-resistant Acinetobacter baumannii (CRAB) in 10 U.S. sites. To describe the impact of the COVID-19 pandemic on the epidemiology of these antibiotic-resistant gram-negative bacteria (AR-GNB), we assessed characteristics of AR-GNB patients with and without a prior SARS-CoV-2 positive (SC2+) viral test. Methods In 2020 among EIP catchment-area residents, an incident CRAB or CRE case was defined as the first isolation of A. baumannii complex, Escherichia coli, Enterobacter cloacae complex, Klebsiella aerogenes, K. oxytoca, K. pneumonia, or K. variicola in a 30-day period resistant to ≥1 carbapenem (excluding ertapenem for CRAB) from a normally sterile site or urine. An incident ESBL-E case was defined as the first isolation of E. coli, K. pneumonia, or K. oxytoca in a 30-day period resistant to any third-generation cephalosporin and non-resistant to all carbapenems from a normally sterile site or urine. Patient charts were reviewed. Results Of 3904 AR-GNB cases with data available, 163 (4%) had a prior SC2+ test (85 ESBL-E, 70 CRE, and 8 CRAB). Median time from the most recent SC2+ test to AR-GNB culture date was 20 days (IQR 1–48 days). AR-GNB cases with a SC2+ test versus those without were more likely to be Black, non-Hispanic than another race/ethnicity (31% vs 15%; P< 0.0001), aged ≥65 years (62% vs 52%; P=0.0139), and to have prior healthcare exposures (63% vs 49%; P=0.0003) and indwelling devices (51% vs 28%; P< 0.0001). They were also more likely to have bacteremia (24% vs 11%; P< 0.0001), pneumonia (6% vs 1%; P< 0.0001) and be hospitalized around the time of their AR-GNB culture (67% vs 36%; P< 0.0001); median time from SC2+ test to hospital admission was 0.5 day (IQR 0–29.5 days). Conclusion AR-GNB infections preceded by a SC2+ test were rare but more severe and associated with more healthcare risk factors. This underscores the need for continued infection prevention and control practices and monitoring of these infections during the COVID-19 pandemic. Disclosures Ghinwa Dumyati, MD, Pfizer: Grant/Research Support.

2054. Trends in Incidence and Epidemiology of Methicillin-Resistant Staphylococcus aureus Bloodstream Infection, 2005–2020

Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA) is a serious antimicrobial resistance threat; prevention efforts have focused primarily on healthcare-associated MRSA infections. We assessed progress in MRSA bloodstream infection (BSI) prevention during 2005-2020. Methods MRSA BSI data were from CDC Emerging Infections Program’s active, population-based surveillance for invasive S. aureus in 17 counties in 6 states (sites). A case was defined as isolation of MRSA from a blood culture in a resident of the catchment area. Cases were considered hospital-onset (HO) if the culture was obtained > 3 days after hospitalization, healthcare-associated community-onset (HACO) if the culture was obtained in an outpatient setting or ≤ 3 days after hospitalization in a patient with ≥ 1 prior major healthcare exposures, or otherwise community-associated (CA). Annual incidence was calculated per 100,000 census population for each epidemiologic classification. Results MRSA BSI incidence decreased from 32.2 (per 100,000 population) in 2005 to a nadir of 15.7 in 2016, then increased during 2017-2019 to 17.0 and decreased in 2020 to 16.4. (Figure 1). HACO comprised > 50% of all cases throughout 2005-2020 and mirrored the pattern of overall rates. HO rates decreased from 9.2 to 2.3 during 2005-2013 and fell below CA rates starting in 2012; rates were lowest during 2017-2019 (1.8-2.1) and increased in 2020 to 2.4. CA rates remained 3.0-4.6 throughout the surveillance period; during 2015-2019, rates increased from 3.0 to 4.0, then in 2020 decreased to 3.4. All sites saw decreases in overall MRSA BSI rates by > 50% during 2005-2020, and HACO rates in 2020 were at least 50% of total rates for each site. However, the relative proportion of CA and HO rates during 2020 varied by site (Figure 2), with CA MRSA BSI more than twice as common as HO MRSA BSI in two sites. Figure 1.Incidence rates of methicillin-resistant Staphylococcus aureus bloodstream infection, by epidemiologic classification, in 6 Emerging Infections Program sites, 2005–2020Figure 2.Ratio of incidence (per 100,000 population) of community-associated (CA) to hospital-onset (HO) methicillin-resistant Staphylococcus aureus bloodstream infection, in 6 Emerging Infections Program sites, 2020 Conclusion MRSA BSI rates fell by more than half during the 15-year surveillance period, reflecting substantial declines in HACO and HO cases; however, the recent plateau suggests a need for additional preventive measures that restore previous progress. Increased focus on CA MRSA BSI prevention may be needed in some areas depending on local epidemiology. Disclosures Ghinwa Dumyati, MD, Pfizer: Grant/Research Support William Schaffner, MD, VBI Vaccines: Advisor/Consultant.

Active Surveillance for Carbapenem-Resistant Enterobacterales (CRE) Colonization and Clinical Course of CRE Colonization among Hospitalized Patients at a University Hospital in Thailand.

Optimal measures for preventing and controlling carbapenem-resistant Enterobacterales (CRE) depend on their burden. This prospective observational study investigated the prevalence and clinical course of CRE colonization in hospitalized patients at Siriraj Hospital, the largest university hospital in Thailand. Stool/rectal swab samples were collected from the patients upon admission, once weekly during hospitalization and every 1–3 months after discharge, to determine the presence of CRE in the stool. Between 2018 and 2021, a total of 528 patients were included. The prevalence of CRE colonization upon admission was 15.5%, while 28.3% of patients who tested negative for CRE on admission acquired CRE during their hospitalization. CRE colonization upon admission was usually associated with prior healthcare exposure. Among CRE-colonized patients, 4.7% developed a CRE clinical infection, with 60% mortality. No cutoff period that ensured that patients were free of CRE colonization in stool was identified, and isolation precautions should only be ceased if stool tests are negative for CRE. In conclusion, the prevalence of CRE colonization among hospitalized patients at Siriraj Hospital is high. CRE-colonized patients are at risk of developing subsequent CRE infection. To prevent CRE transmission within the hospital, patients at high risk of colonization should undergo CRE screening upon admission.

Characteristics of community-acquired carbapenem-resistant Enterobacterales.

Community-acquired carbapenem-resistant Enterobacterales (CA-CRE) are an important threat. In CRACKLE-2, we defined patients with CA-CRE as admitted from home, without pre-existing conditions, and a positive culture within 48 h of admission. Healthcare-associated CRE (HA-CRE) were those with the lowest likelihood of community acquisition, not admitted from home and cultured >48 h after admission. Specific genetic markers in carbapenemase-producing Klebsiella pneumoniae were evaluated through random forest modelling. CA-CRE and HA-CRE were detected in 83 (10%) and 208 (26%) of 807 patients. No significant differences were observed in bacterial species or strain type distribution. K. pneumoniae (204/291, 70%) was the most common CRE species, of these 184/204 (90%) were carbapenemase producers (CPKP). The top three genetic markers in random forest models were kpi_SA15, fimE, and kpfC. Of these, kpi_SA15 (which encodes a chaperone/usher system) was positively associated (OR 3.14, 95% CI 1.13-8.87, P = 0.026), and kpfC negatively associated (OR 0.21, 95% CI 0.05-0.72, P = 0.015) with CA-CPKP. Ten percent of CDC-defined CRE were CA. The true proportion of CA-CRE in hospitalized patients is likely lower as patients may have had unrecorded prior healthcare exposure. The kpi_SA15 operon was associated with the CA phenotype.

Recruiting males to the nursing profession: acceptability testing of the ‘Make a Difference with Nursing’ intervention for post-primary school students

BackgroundThe nursing profession is facing a worldwide recruitment shortage which could be partially addressed by recruiting more males. However, in many developed countries numbers of male nurses have traditionally been low. To address this issue we developed and tested a post-primary school-based intervention to recruit more males into the nursing profession.MethodsParticipants included thirty-four female students drawn from an all-girls post-primary school, fifty-one males from an all-boys post-primary school and seven males and fifteen females drawn from a mixed gender post-primary school, all located in Northern Ireland. Participants were all sixteen years of age and were in receipt of careers education. The intervention titled ‘Make a Difference with Nursing’ was co-designed with careers teachers, nurses and post-primary school students. This video based intervention was created to fit within existing career lessons and featured nursing staff and students describing their experiences of the profession. Participants completed the six domains of Nursing as a Career Choice Questionnaire prior to viewing the intervention and again after viewing.ResultsPositive and statistically significant increases in perceptions of the nursing profession were found between pre and post test scores across all six domains. No statistically significant differences in perceptions were found between males and females after watching the intervention. Comparison by school type showed statistically significant differences on the domains of prior healthcare exposure (p = 0.046; 95% CI -0.19 to 3.79) and job prospects (p = 0.005; 95% CI 1.04 to 7.01). Students from the all-girls school rated these more positively than those from the all-boys and mixed-gender schools.ConclusionsA short video presentation to post-primary school students is capable of changing how they perceive the nursing profession. Students expressed surprise over the variety of professional nursing roles suggesting that many were not well informed about the realities of nursing. Providing tailored resources for use in careers lessons can better educate students and teachers about nursing and provide positive portrayals of male role models in the profession.

Inpatient point-prevalence screening of New Delhi Metallo-β-lactamase (NDM)–producing Enterobacaterales and Candida auris

Background: Carbapenem-resistant Enterobacterales (CRE) are an increasing threat to patient safety but only a small percentage of CRE identified are NDMs. Since 2018, clinical CRE isolates have been submitted to the Ohio Department of Health for sequencing and NDM cases have notably increased since that time. Candida auris is an emerging pathogen with similar risk factors for colonization as CRE. Methods: A point-prevalence study was initiated after an index patient was identified with NDM CRE infection or colonization during their inpatient admission. Two patient populations were included in the study: current patients on the same unit as the index patient and currently hospitalized patients who overlapped on any unit with the index patient for at least 72 hours. Patients had perirectal screening for CRE (via PCR) and axilla or groin screening for C. auris (via Xpert Carba-R Assay). Patients were excluded if they had been discharged, expired, or refused testing. Results: We completed 5 point-prevalence studies from March 21, 2021, to October 15, 2021. The index patients were admitted at different times and across 2 campuses including medical, cardiac, and surgical ICUs as well as medical-surgical and inpatient rehabilitation units. Moreover, 3 species of NDM were identified from urine and 2 species were identified from bronchoalveolar lavage: Enterobacter hormaechei, Citrobacter freundii, and Enterobacter cloacae complex. C. freundii and E. cloacae complex both had dual mechanisms of NDM and KPC. Although some of the index patients overlapped temporally within the health system, none overlapped in the same unit or building. None of the patients had recently received health care outside the United States, although 1 patient had emigrated from Togo >5 years prior and 4 had had prior local healthcare exposure within 12 months of admission. Also, 147 patients were identified for screening; 105 consented, 32 declined, and 10 were excluded due to being discharged, deceased, or unable to consent. Inpatient point-prevalence screening tests for all patients tested (n = 105) were negative for NDM CRE and C. auris. Conclusions: Despite an increase of inpatients with NDM CRE, evidence of patient-to-patient transmission was not identified, likely resulting from adherence to standard precautions. The diversity of species and lack of international travel suggests that these patients likely acquired NDM CRE from a local reservoir in the community or healthcare settings. Given the continued increase in NDM CRE without traditional risk factors, it is critical for hospitals and public health agencies to collaborate to identify these organisms and that they develop surveillance programs to clarify risk factors for colonization.Funding: NoneDisclosures: None

Management of Pseudomonas aeruginosa Bloodstream Infection and Impact on Health Outcomes

Background: Gram-negative bacteria cause a variety of hospital-associated infections (HAIs). Of concern is Pseudomonas aeruginosa, which is a leading cause of HAIs. Early and adequate therapy of P. aeruginosa blood stream infection (BSI) is associated with decreased mortality. Additionally, infectious disease consultation has also shown to improve health outcomes, streamline care, and decrease costs. Therefore, the goal of this study was to describe treatment of P. aeruginosa BSI and impact of infectious disease consultations on health outcomes. Methods: In this retrospective cohort study, we analyzed national VA medical, encounter, pharmacy, microbiology, and laboratory data from January 1, 2012 to December 31, 2018. The cohort included all hospitalized adult veterans (aged ≥18 years) who had a positive blood culture for P. aeruginosa. Only the first P. aeruginosa blood culture per patient was included, and duplicate cultures within 30 days were removed. Treatment was identified within −2 to +5 days of the culture date. Multidrug-resistant (MDR) cultures were identified based on resistance to at least 1 agent in at least 3 or more antimicrobial categories tested. Multivariable logistic regression models were fit to assess infectious disease consultations and adequate treatment on in-hospital mortality and 30-day mortality. Results: In total, 3,256 patients had a BSI with P. aeruginosa, of which 386 (11.5%) were MDR. Most of these patients were male (97.5%), >65 years of age (70.9%), and non-Hispanic white (63.8%). Also, 784 patients (23.3%) died during hospitalization and 870 (25.8%) died within 30 days of their culture. In multivariable regression models, infectious disease consultations were associated with decreased odds of in-hospital mortality (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.53–0.77) and 30-day mortality (OR, 0.56, 95% CI, 0.48–0.67) even after adjusting for age, race, care setting, Charlson score, and prior healthcare exposures. Furthermore, inadequate definitive treatment was associated with increased odds of in-hospital mortality (OR, 2.77; 95% CI, 1.35–5.69) and 30-day mortality (OR, 2.37; 95% CI, 1.18–4.79), even after adjusting for age, Charlson score, care setting, and prior healthcare exposures. In addition, carbapenem treatment was associated with increased odds of in-hospital mortality (OR, 1.38; 95% CI, 1.12–1.70) and 30-day mortality (OR, 1.49; 95% CI, 1.22–1.81), whereas fluoroquinolone treatment was associated with lower odds of in-hospital mortality (OR, 0.49; 95% CI, 0.41–0.59) and 30-day mortality (OR, 0.60; 95% CI, 0.50–0.71). Finally, extended-spectrum cephalosporin was also associated with lower odds of in-hospital mortality (OR, 0.82; 95% CI, 0.68–0.98). Conclusions: Use of infectious disease consultations and any adequate definitive treatment for those with P. aeruginosa BSI lowered odds of in-hospital and 30-day mortality. Early consultation with infectious disease physicians regarding adequate treatment has direct positive impact on clinical outcomes for patients with P. aeruginosa BSI.Funding: NoDisclosures: None

Risk for Clostridioides difficile Infection Among Hospitalized Patients Associated With Multiple Healthcare Exposures Prior to Admission.

Clostridioides difficile infection (CDI) is a common healthcare-associated infection and is often used as an indicator of hospital safety or quality. However, healthcare exposures occurring prior to hospitalization may increase risk for CDI. We conducted a case-control study comparing hospitalized patients with and without CDI to determine if healthcare exposures prior to hospitalization (ie, clinic visits, antibiotics, family members with CDI) were associated with increased risk for hospital-onset CDI, and how risk varied with time between exposure and hospitalization. Records were collected from a large insurance-claims database from 2001 to 2017 for hospitalized adult patients. Prior healthcare exposures were identified using inpatient, outpatient, emergency department, and prescription drug claims; results were compared between various CDI case definitions. Hospitalized patients with CDI had significantly more frequent healthcare exposures prior to admission. Healthcare visits, antibiotic use, and family exposures were associated with greater likelihood of CDI during hospitalization. The degree of association diminished with time between exposure and hospitalization. Results were consistent across CDI case definitions. Many different prior healthcare exposures appear to increase risk for CDI presenting during hospitalization. Moreover, patients with CDI typically have multiple exposures prior to admission, confounding the ability to attribute cases to a particular stay.

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.