- [Show abstract] [Hide abstract] ABSTRACT: OBJECTIVE To describe antimicrobial resistance patterns for healthcare-associated infections (HAIs) that occurred in 2011-2014 and were reported to the Centers for Disease Control and Prevention's National Healthcare Safety Network. METHODS Data from central line-associated bloodstream infections, catheter-associated urinary tract infections, ventilator-associated pneumonias, and surgical site infections were analyzed. These HAIs were reported from acute care hospitals, long-term acute care hospitals, and inpatient rehabilitation facilities. Pooled mean proportions of pathogens that tested resistant (or nonsusceptible) to selected antimicrobials were calculated by year and HAI type. RESULTS Overall, 4,515 hospitals reported that at least 1 HAI occurred in 2011-2014. There were 408,151 pathogens from 365,490 HAIs reported to the National Healthcare Safety Network, most of which were reported from acute care hospitals with greater than 200 beds. Fifteen pathogen groups accounted for 87% of reported pathogens; the most common included Escherichia coli (15%), Staphylococcus aureus (12%), Klebsiella species (8%), and coagulase-negative staphylococci (8%). In general, the proportion of isolates with common resistance phenotypes was higher among device-associated HAIs compared with surgical site infections. Although the percent resistance for most phenotypes was similar to earlier reports, an increase in the magnitude of the resistance percentages among E. coli pathogens was noted, especially related to fluoroquinolone resistance. CONCLUSION This report represents a national summary of antimicrobial resistance among select HAIs and phenotypes. The distribution of frequent pathogens and some resistance patterns appear to have changed from 2009-2010, highlighting the need for continual, careful monitoring of these data across the spectrum of HAI types. Infect Control Hosp Epidemiol 2016;1-14.
- [Show abstract] [Hide abstract] ABSTRACT: Reports of bloodstream infections caused by methicillin-resistant Staphylococcus aureus among chronic hemodialysis patients to 2 Centers for Disease Control and Prevention surveillance systems (National Healthcare Safety Network Dialysis Event and Emerging Infections Program) were compared to evaluate completeness of reporting. Many methicillin-resistant S. aureus bloodstream infections identified in hospitals were not reported to National Healthcare Safety Network Dialysis Event. Infect. Control Hosp. Epidemiol. 2015;00(0):1–3
- [Show abstract] [Hide abstract] ABSTRACT: DISCLOSURE The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention or the Agency for Toxic Substances and Diseases Registry. OBJECTIVE Describe the impact of standardizing state-specific summary measures of antibiotic resistance that inform regional interventions to reduce transmission of resistant pathogens in healthcare settings. DESIGN Analysis of public health surveillance data. METHODS Central line-associated bloodstream infection (CLABSI) data from intensive care units (ICUs) of facilities reporting to the National Healthcare Safety Network in 2011 were analyzed. For CLABSI due to methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum cephalosporin (ESC)-nonsusceptible Klebsiella species, and carbapenem-nonsusceptible Klebsiella species, we computed 3 state-level summary measures of nonsusceptibility: crude percent nonsusceptible, model-based adjusted percent nonsusceptible, and crude infection incidence rate. RESULTS Overall, 1,791 facilities reported CLABSIs from ICU patients. Of 1,618 S. aureus CLABSIs with methicillin-susceptibility test results, 791 (48.9%) were due to MRSA. Of 756 Klebsiella CLABSIs with ESC-susceptibility test results, 209 (27.7%) were due to ESC-nonsusceptible Klebsiella, and among 661 Klebsiella CLABSI with carbapenem susceptibility test results, 70 (10.6%) were due to carbapenem-nonsusceptible Klebsiella. All 3 state-specific measures demonstrated variability in magnitude by state. Adjusted measures, with few exceptions, were not appreciably different from crude values for any phenotypes. When linking values of crude and adjusted percent nonsusceptible by state, a state's absolute rank shifted slightly for MRSA in 5 instances and only once each for ESC-nonsusceptible and carbapenem-nonsusceptible Klebsiella species. Infection incidence measures correlated strongly with both percent nonsusceptibility measures. CONCLUSIONS Crude state-level summary measures, based on existing NHSN CLABSI data, may suffice to assess geographic variability in antibiotic resistance. As additional variables related to antibiotic resistance become available, risk-adjusted summary measures are preferable. Infect Control Hosp Epidemiol 2015;36(1): 54-64.
- [Show abstract] [Hide abstract] ABSTRACT: Brief Summary The collaborations that the Centers for Disease Control and Prevention’s (CDC’s) National Healthcare Safety Network (NHSN) Team has with the Council of State and Territorial Epidemiologists (CSTE) and the Centers for Medicare and Medicaid Services (CMS) provide important momentum for advances in healthcare-associated infection (HAI) surveillance at the local, state, and federal levels. The work that has been accomplished and new efforts underway continue to extend NHSN’s capacity to produce accurate and valid surveillance data for effective prevention of HAIs in a variety of healthcare settings. As a result of state and CMS requirements, NHSN has emerged as the primary system used for HAI surveillance and reporting in the U.S. This development, in turn, has led to important changes and improvements to NHSN. These changes have been implemented for the purposes of reducing subjectivity, maximizing standardization, preventing data entry errors, improving simplicity and completeness of data entry, and more accurately defining the facility types and locations from which data are reported. Major enhancements include revisions and additions to better standardize HAI criteria and definitions and risk adjust metrics for comparative purposes, new reporting for antimicrobial resistance data, and additional output options for analysis and reports. The NHSN system is also stabilized with architecture upgrades as necessary. Electronic reporting capability through Clinical Document Architecture (CDA) will be expanded to include antimicrobial resistance reporting through the Antimicrobial Use and Resistance Module and always includes enhancements for improved reporting. New additions planned for the NHSN system include a new Component specifically for Dialysis Event reporting and the Outpatient Procedure Component for reporting from Ambulatory Surgery Centers. Together the revisions serve to improve the user interaction and experience with NHSN and the completeness and quality of the data that are analyzed and reported out of the system. During this session users will be asked to provide feedback and input on current and future enhancements to the NHSN system. The impact of state mandates and CMS rules to users, stakeholders, and the system will be discussed as a group. The intent is to make this an informative and interactive NHSN presentation and discussion.
- [Show abstract] [Hide abstract] ABSTRACT: Background Case series have described severe lower respiratory tract infection (LRI) in healthy, community-dwelling persons caused by methicillin-resistant Staphylococcus aureus (MRSA). Evaluating populations at risk is needed. Methods Surveillance for patients aged 50 years or younger hospitalized with LRI who had S aureus isolated from blood or respiratory specimen during September 2008 to August 2010 was performed at 25 hospitals in 5 US metropolitan areas. Persons with recent health care exposure were excluded. Lower respiratory tract infection diagnosis required supporting radiographic or clinical evidence. Clinical characteristics of LRI were compared by methicillin resistance phenotype. Results In total, 94 hospitalized community-onset S aureus LRI cases were identified. Lower respiratory tract infection cases were identified in both young adults and children (60%, 35–50 years; and 19%, younger than 17 years), without any seasonality or association with influenza circulation. Among the 94 case patients with LRI, 34 patients (36%) had bacteremia, 36 patients (40%) required ICU admission, and 6 patients (6%) died; proportions were similar between cases with methicillin-susceptible S aureus and MRSA. Lower respiratory tract infection cases with MRSA had longer median length of stay compared with those with methicillin-susceptible S aureus (9 vs. 6 days; P = 0.04). Lower respiratory tract infection cases with evidence of influenza infection had higher mortality compared with LRI cases without influenza infection (31% vs. 2%; P = 0.003). During influenza circulation, 35 (55%) of 64 case patients with LRI were tested for influenza, and 9 (26%) of the 35 case patients tested positive. Conclusions S aureus LRI occurred in both adults and children, without any seasonality or association with MRSA and with and without evidence of influenza infection, although case fatality was higher among those with evidence of influenza infection.
- [Show abstract] [Hide abstract] ABSTRACT: BACKGROUND: During 2011, 3472 facilities from 50 states, the District of Columbia (DC), and Puerto Rico (PR) reported central line-associated bloodstream infections (CLABSIs) to the Centers for Disease Control and Prevention’s (CDC’s) National Healthcare Safety Network. As requested by states/territories (S/T), CDC includes notation indicating which S/T health departments have validated healthcare-associated infection data in its annual National and State Standardized Infection Ratio (SIR) Report. To evaluate for association between S/T validation activities and reporting, we used 2011 SIR report data to compare SIRs in S/T with varying extents of CLABSI validation. METHODS: Using information provided by S/T for the 2011 CDC SIR Report, S/T were divided into three strata: A) S/T conducting external validation (i.e., medical records audits), B) S/T assisting facilities with internal validation (i.e., data analysis to investigate and correct aberrancies), and C) S/T not conducting validation for 2011 CLABSI data. Overall SIRs and percentile distributions of facility-level SIRs within strata were calculated. Comparisons were made between strata in overall SIRs, median facility SIRs, and distribution of facility SIRs. RESULTS: SIRs were calculated for the 3 S/T validation strata, including CLABSI data from all patient-care locations with baseline information, reported by 3468 facilities. Stratum A included 1175 facilities from thirteen states plus DC; stratum B included 780 facilities from 11 states; and stratum C included 1513 facilities from 26 states plus PR. CLABSI SIRs were higher for stratum A vs. stratum B (0.622 vs.0.578, p=0.0002) and stratum A vs. stratum C (0.622 vs. 0.567, p<0.0001), but not different for stratum B vs. stratum C (0.578 vs. 0.567, p=0.3585). The 2335 facilities with at least one predicted CLABSI (851 (72%) of stratum A facilities, 487 (62%) of stratum B facilities, and 997 (66%) of stratum C facilities) contributed to analyses of stratum-specific median SIR and SIR distribution. The median facility SIR was higher for stratum A vs. stratum C (0.503 vs. 0.418, p=0.0028) and stratum B vs. stratum C (0.500 vs. 0.418, p=0.0094). The stratum-specific distribution of facility SIRs was shifted toward higher SIRs for both stratum A (p=0.0142) and stratum B (p=0.0292) vs. stratum C. CONCLUSIONS: In 2011, S/T CLABSI validation activities were associated with higher stratum-specific SIRs, median facility-level SIRs, and SIR distributions. Factors underlying this association may include increased completeness of reporting due to greater oversight and accountability. Monitoring of this association should continue and S/T validation should expand to maximize accountability, fairness, and data quality in all jurisdictions.
- [Show abstract] [Hide abstract] ABSTRACT: Brief Summary The collaborations that the Centers for Disease Control and Prevention’s (CDC’s) National Healthcare Safety Network (NHSN) Team has with the Council of State and Territorial Epidemiologists (CSTE) and the Centers for Medicare and Medicaid Services (CMS) provide important momentum for advances in healthcare-associated infection (HAI) surveillance at the local, state, and federal levels. The work that has been accomplished and new efforts underway are extending NHSN’s capacity to produce accurate and valid surveillance data for effective prevention of HAIs in a variety of healthcare settings. As a result of state and CMS requirements, NHSN has emerged as the primary system used for HAI surveillance and reporting in the U.S. This development, in turn, has led to important changes and improvements to NHSN. These changes have been implemented for the purposes of reducing subjectivity, maximizing standardization, preventing data entry errors, improving simplicity and completeness of data entry, and more accurately defining the facility types and locations from which data are reported. The major recent enhancements include revisions made to better standardize HAI criteria and definitions, new alerts and reporting simplifications for antimicrobial resistance data, additional output options for analysis and reports, more accurately defined locations for certain facility types, and new reporting options, including Mucosal Barrier Injury for CLABSIs and Ventilator-Associated Event reporting. The NHSN system is also stabilized with additional servers and architecture upgrades as necessary. Electronic reporting capability through Clinical Document Architecture (CDA) will be expanded to include antimicrobial resistance reporting through the Antimicrobial Use and Resistance Module and always includes enhancements for improved reporting. New additions coming soon to the NHSN system include the Outpatient Procedure Component and a new Component specifically for Dialysis Event reporting. Together these revisions serve to improve the user interaction and experience with NHSN and the quality of the data that are analyzed and reported out of the system. During this session users will be asked to provide feedback and input on current and future enhancements to the NHSN system. The impact of state mandates and CMS rules to users, stakeholders, and the system will be discussed as a group. The intent is to make this an informative and interactive NHSN presentation and discussion.
- [Show abstract] [Hide abstract] ABSTRACT: Objective: To describe antimicrobial resistance patterns for healthcare-associated infections (HAIs) reported to the National Healthcare Safety Network (NHSN) during 2009-2010. Methods: Central line-associated bloodstream infections, catheter-associated urinary tract infections, ventilator-associated pneumonia, and surgical site infections were included. Pooled mean proportions of isolates interpreted as resistant (or, in some cases, nonsusceptible) to selected antimicrobial agents were calculated by type of HAI and compared to historical data. Results: Overall, 2,039 hospitals reported 1 or more HAIs; 1,749 (86%) were general acute care hospitals, and 1,143 (56%) had fewer than 200 beds. There were 69,475 HAIs and 81,139 pathogens reported. Eight pathogen groups accounted for about 80% of reported pathogens: Staphylococcus aureus (16%), Enterococcus spp. (14%), Escherichia coli (12%), coagulase-negative staphylococci (11%), Candida spp. (9%), Klebsiella pneumoniae (and Klebsiella oxytoca; 8%), Pseudomonas aeruginosa (8%), and Enterobacter spp. (5%). The percentage of resistance was similar to that reported in the previous 2-year period, with a slight decrease in the percentage of S. aureus resistant to oxacillins (MRSA). Nearly 20% of pathogens reported from all HAIs were the following multidrug-resistant phenotypes: MRSA (8.5%); vancomycin-resistant Enterococcus (3%); extended-spectrum cephalosporin-resistant K. pneumoniae and K. oxytoca (2%), E. coli (2%), and Enterobacter spp. (2%); and carbapenem-resistant P. aeruginosa (2%), K. pneumoniae/oxytoca (<1%), E. coli (<1%), and Enterobacter spp. (<1%). Among facilities reporting HAIs with 1 of the above gram-negative bacteria, 20%-40% reported at least 1 with the resistant phenotype. Conclusion: While the proportion of resistant isolates did not substantially change from that in the previous 2 years, multidrug-resistant gram-negative phenotypes were reported from a moderate proportion of facilities.
- [Show abstract] [Hide abstract] ABSTRACT: Background: The Multidrug-Resistant Organism and Clostridium difficile Infection (MDRO/CDI) Module was implemented in the National Healthcare Safety Network (NHSN) in March 2009 to allow reporting of CDI, methicillin-resistant Staphylococcus aureus (MRSA), and other MDROs. State mandated reporting drove initial participation, but the Centers for Medicare and Medicaid Services will incentivize reporting of these two infections from acute care hospitals beginning in 2013. The use of these data for inter-facility comparisons and public reporting highlight the immediate need for adequate risk adjustment methods. Methods: During 2010-2011, participating facilities reported all unique positive specimens (collected >14 days after a previous positive specimen) for CDI and MRSA bacteremia (blood specimens) to NHSN. Events were categorized as community-onset (CO, collected ≤3 days after admission) or healthcare facility-onset (HO, collected >3 days after admission). HO CDI and HO MRSA bacteremia incidence rates (per 10,000 and 1,000 patient-days, respectively) were calculated and compared by facility characteristics to identify potential risk adjustment variables using negative binomial testing. Results: In 2010, 715 facilities from 28 states monitored CDI events in NHSN. A total of 20,803 HO CDI events were reported from 5,757,846 admissions and 28,279,284 patient-days. CDI incidence rates differed significantly by facility teaching type, bedsize, test type, and CO prevalence (Table). MRSA bacteremia was monitored in 548 facilities from 29 states. A total of 1,078 HO MRSA bacteremia events were reported from 3,807,920 admissions and 17,427,005 patient-days. MRSA bacteremia incidence rates differed significantly by teaching type and bedsize. Conclusion: These facility characteristics will be assessed using multivariable analysis to determine risk adjustment for the HO CDI and HO MRSA bacteremia Standardized Infection Ratios (SIRs). CDI MRSA Bacteremia Rate p-value Rate p-value Teaching Type Major 8.6 --- 0.1 --- All Other 6.7 <0.0001 0.05 <0.0001 Facility Bedsize ≤200 6.7 --- 0.05 --- 201-500 7.0 0.0005 0.05 --- 501+ 8.9 <0.0001 0.1 <0.0001 Test Type PCR 8.3 --- --- --- All Other 6.6 <0.0001 --- --- CO Prevalence Continuous <0.0001 --- ---
- [Show abstract] [Hide abstract] ABSTRACT: Objective. To evaluate national data on healthcare-associated infections (HAIs), device utilization, and antimicrobial resistance in long-term acute care hospitals (LTACHs). Design and setting. Comparison of data from LTACHs and from medical and medical-surgical intensive care units (ICUs) in short-stay acute care hospitals reporting to the National Healthcare Safety Network (NHSN) during 2010. Methods. Rates of central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), and ventilator-associated pneumonia (VAP) as well as device utilization ratios were calculated. For each HAI, pathogen profiles and antimicrobial resistance prevalence were evaluated. Comparisons were made using Poisson regression and the Mood median and χ(2) tests. Results. In 2010, 104 LTACHs reported CLABSIs and 57 reported CAUTIs and VAP to the NHSN. Median CLABSI rates in LTACHs (1.25 events per 1,000 device-days reported; range, 0.0-5.96) were comparable to rates in major teaching ICUs and were higher than those in other ICUs. CAUTI rates in LTACHs (median, 2.61; range, 0.0-9.92) were higher and VAP rates (median, 0.0; range, 0.0-3.29) were generally lower than those in ICUs. Central line utilization in LTACHs was higher than that in ICUs, whereas urinary catheter and ventilator utilization was lower. Methicillin resistance among Staphylococcus aureus CLABSIs (83%) and vancomycin resistance among Enterococcus faecalis CAUTIs (44%) were higher in LTACHs than in ICUs. Multidrug resistance among Pseudomonas aeruginosa CAUTIs (25%) was higher in LTACHs than in most ICUs. Conclusions. CLABSIs and CAUTIs associated with multidrug-resistant organisms present a challenge in LTACHs. Continued HAI surveillance with pathogen-level data can guide prevention efforts in LTACHs.
- [Show abstract] [Hide abstract] ABSTRACT: Background: Clostridium difficile infection (CDI) is a common and sometimes fatal health-care-associated infection; the incidence, deaths, and excess health-care costs resulting from CDIs in hospitalized patients are all at historic highs. Meanwhile, the contribution of nonhospital health-care exposures to the overall burden of CDI, and the ability of programs to prevent CDIs by implementing CDC recommendations across a range of hospitals, have not been demonstrated previously. Methods: Population-based data from the Emerging Infections Program were analyzed by location and antecedent health-care exposures. Present-on-admission and hospital-onset, laboratory-identified CDIs reported to the National Healthcare Safety Network (NHSN) were analyzed. Rates of hospital-onset CDIs were compared between two 8-month periods near the beginning and end of three CDI prevention programs that focused primarily on measures to prevent intrahospital transmission of C. difficile in three states (Illinois, Massachusetts, and New York). Results: Among CDIs identified in Emerging Infections Program data in 2010, 94% were associated with receiving health care; of these, 75% had onset among persons not currently hospitalized, including recently discharged patients, outpatients, and nursing home residents. Among CDIs reported to NHSN in 2010, 52% were already present on hospital admission, although they were largely health-care related. The pooled CDI rate declined 20% among 71 hospitals participating in the CDI prevention programs. Conclusions: Nearly all CDIs are related to various health-care settings where predisposing antibiotics are prescribed and C. difficile transmission occurs. Hospital-onset CDIs were prevented through an emphasis on infection control. Implications for Public Health: More needs to be done to prevent CDIs; major reductions will require antibiotic stewardship along with infection control applied to nursing homes and ambulatory-care settings as well as hospitals. State health departments and partner organizations have shown leadership in preventing CDIs in hospitals and can prevent more CDIs by extending their programs to cover other health-care settings.
- [Show abstract] [Hide abstract] ABSTRACT: Background: Methicillin-resistant Staphylococcus aureus (MRSA) infections are often defined as health care (HA) or community-associated (CA) using common classification schemes involving health care risk factor, infection type, susceptibility pattern, or molecular typing. This investigation compared pulsed-field gel electrophoresis (PFGE) molecular typing results (dichotomized as HA or CA) with our new MRSA infection classification method. The goal was to develop an improved predictive model for PFGE-type based primarily on the other 3 classification variables. Methods: Methicillin-resistant S. aureus infections reported to the Michigan Department of Community Health from October 2004 to December 2005 were analyzed. Patients’ demographics, risk factors, infection information, and susceptibility results were collected for 2151 cases. A subset of 244 MRSA infections with available PFGE results was analyzed. Results of logistic regression are presented using a receiver operating characteristic curve analysis. Results: The multivariable models predicted the PFGE classification as HA or CA (Max-rescaled R2 = 61%) better than health care risk factor, infection type, or susceptibility pattern alone (max-rescaled R2 = 21%, 34%, and 46%, respectively). The best model included infection type, susceptibility pattern, age, and hospitalized during infection. Conclusions: This model provides a simpler, more accurate prediction of HA or CA status, thus enhancing efforts to control MRSA infections.
- [Show abstract] [Hide abstract] ABSTRACT: Expanding hospitalized patients' risk stratification for Clostridium difficile infection (CDI) is important for improving patient safety. We applied definitions for hospital-onset (HO) and community-onset (CO) CDI to electronic data from 85 hospitals between January 2007 and June 2008 to identify factors associated with higher HO CDI rates. Nonrecurrent CDI cases were identified among adult (≥ 18-year-old) inpatients by a positive C. difficile toxin assay result more than 8 weeks after any previous positive result. Case categories included HO, CO-hospital associated (CO-HA), CO-indeterminate hospital association (CO-IN), and CO-non-hospital associated (CO-NHA). C. difficile testing intensity (CDTI) was defined as the total number of C. difficile tests performed, normalized to the number of patients with at least 1 C. difficile toxin test recorded. We calculated both the incidence density and the prevalence of CDI where appropriate. We fitted a multivariable Poisson model to identify factors associated with higher HO CDI rates. Among 1,351,156 unique patients with 2,022,213 admissions, 9,803 cases of CDI were identified; of these, 50.6% were HO, 17.4% were CO-HA, 9.0% were CO-IN, and 23.0% were CO-NHA. The incidence density of HO was 6.3 per 10,000 patient-days. The prevalence of CO CDI on admission was, per 10,000 admissions, 8.4 for CO-HA, 4.4 for CO-IN, and 11.1 for CO-NHA. Factors associated (P < .0001) with higher HO CDI rates included older age, higher CO-NHA prevalence on admission, and increased CDTI. Electronic health information can be leveraged to risk-stratify HO CDI rates by patient age and CO-NHA prevalence on admission. Hospitals should optimize diagnostic testing to improve patient care and measured CDI rates.
- [Show abstract] [Hide abstract] ABSTRACT: In September 2008, the Council of State and Territorial Epidemiologists and the Centers for Disease Control and Prevention sponsored a meeting of public health and infection-control professionals to address the implementation of surveillance for multidrug-resistant organisms (MDROs)-particularly those related to health care-associated infections. The group discussed the role of health departments and defined goals for future surveillance activities. Participants identified the following main points: (1) surveillance should guide prevention and infection-control activities, (2) an MDRO surveillance system should be adaptable and not organism specific, (3) new systems should utilize and link existing systems, and (4) automated electronic laboratory reporting will be an important component of surveillance but will take time to develop. Current MDRO reporting mandates and surveillance methods vary across states and localities. Health departments that have not already done so should be proactive in determining what type of system, if any, will fit their needs.
- [Show abstract] [Hide abstract] ABSTRACT: We compared 3 methods for classifying methicillin-resistant Staphylococcus aureus (MRSA) infections as health care associated or community associated for use in public health surveillance. We analyzed data on MRSA infections reported to the Michigan Department of Community Health from October 1, 2004, to December 31, 2005. Patient demographics, risk factors, infection information, and susceptibility were collected for 2151 cases. We classified each case by the health care risk factor, infection-type, and susceptibility pattern methods and compared the results of the 3 methods. Demographic, clinical, and microbiological variables yielded similar health care-associated and community-associated distributions when classified by risk factor and infection type. When 2 methods yielded the same classifications, the overall distribution was similar to classification by 3 methods. No specific combination of 2 methods was superior. MRSA categorization by 2 methods is more accurate than it is by a single method. The health care risk factor and infection-type methods yield comparable classification results. Accuracy is increased by using more variables; however, further research is needed to identify the optimal combination.
- [Show abstract] [Hide abstract] ABSTRACT: Background: A position paper from SHEA/HICPAC suggests that monitoring methicillin-resistant Staphylococcus aureus (MRSA) healthcare-associated infections (HAIs) by patient-care area is critically important to identify hospital locations at high risk for transmission of infection. However, national data on all types of MRSA HAIs by patient location is currently lacking. Objective: Describe MRSA HAIs reported from various patient-care locations in a large sample of U.S. hospitals. Methods: Data on all MRSA HAIs reported to the National Healthcare Safety Network (NHSN) Multidrug-Resistant Organism (MDRO) and Clostridium difficile-Associated Disease (CDAD) Module in 2009 were analyzed. Facility users were instructed to report all MRSA HAIs identified within monitored patient locations regardless of device use. An MRSA HAI incidence rate (MRSA HAIs / 1,000 patient-days) was calculated for each facility-defined patient unit (unit-specific), and data were also summed across all units of the same type for a pooled mean MRSA HAI incidence rate (location-specific). Differences in type of HAI were also evaluated by select locations. Results: A total of 403 facilities performed MRSA infection surveillance in ≥ 1 unit for ≥ 1 month between January and September 2009. Of these, 197 reported no MRSA HAIs; the remaining reported 915 MRSA HAIs from 317 facility-defined patient units which mapped to 38 different location types. Most reporting facilities were general hospitals and 54% had ≤ 200 beds. Of all MRSA HAIs reported, 55% were among males. Mean patient age was 58 years (range: 0-102). The median unit-specific MRSA HAI rate was 0, regardless of location type. The pooled mean MRSA incidence rates and the distributions of specific HAI types varied by location type (Table 1): the highest pooled mean MRSA HAI rate was in surgical intensive care units (ICUs), followed by medical ICUs. Rates in the medical and medical-surgical ICUs were not remarkably higher than among the select patient wards. Pneumonia (PNEU) was the most common infection reported in all three ICU types, skin and soft tissue infections (SST) were most common in the medical and medical-surgical wards, and surgical site infections (SSI) represented half of all infections reported from surgical wards (Table 1). Conclusions: Bloodstream infections (BSI) represent a minority of the MRSA HAI identified from the select locations evaluated. Although data are preliminary, hospital wards had MRSA infection incidence rates comparable to the ICUs. Focusing MRSA surveillance only on BSI in ICUs may overlook a large proportion of the patient population at high risk for MRSA infections.
- [Show abstract] [Hide abstract] ABSTRACT: To describe the frequency of selected antimicrobial resistance patterns among pathogens causing device-associated and procedure-associated healthcare-associated infections (HAIs) reported by hospitals in the National Healthcare Safety Network (NHSN). Data are included on HAIs (ie, central line-associated bloodstream infections, catheter-associated urinary tract infections, ventilator-associated pneumonia, and surgical site infections) reported to the Patient Safety Component of the NHSN between January 2006 and October 2007. The results of antimicrobial susceptibility testing of up to 3 pathogenic isolates per HAI by a hospital were evaluated to define antimicrobial-resistance in the pathogenic isolates. The pooled mean proportions of pathogenic isolates interpreted as resistant to selected antimicrobial agents were calculated by type of HAI and overall. The incidence rates of specific device-associated infections were calculated for selected antimicrobial-resistant pathogens according to type of patient care area; the variability in the reported rates is described. Overall, 463 hospitals reported 1 or more HAIs: 412 (89%) were general acute care hospitals, and 309 (67%) had 200-1,000 beds. There were 28,502 HAIs reported among 25,384 patients. The 10 most common pathogens (accounting for 84% of any HAIs) were coagulase-negative staphylococci (15%), Staphylococcus aureus (15%), Enterococcus species (12%), Candida species (11%), Escherichia coli (10%), Pseudomonas aeruginosa (8%), Klebsiella pneumoniae (6%), Enterobacter species (5%), Acinetobacter baumannii (3%), and Klebsiella oxytoca (2%). The pooled mean proportion of pathogenic isolates resistant to antimicrobial agents varied significantly across types of HAI for some pathogen-antimicrobial combinations. As many as 16% of all HAIs were associated with the following multidrug-resistant pathogens: methicillin-resistant S. aureus (8% of HAIs), vancomycin-resistant Enterococcus faecium (4%), carbapenem-resistant P. aeruginosa (2%), extended-spectrum cephalosporin-resistant K. pneumoniae (1%), extended-spectrum cephalosporin-resistant E. coli (0.5%), and carbapenem-resistant A. baumannii, K. pneumoniae, K. oxytoca, and E. coli (0.5%). Nationwide, the majority of units reported no HAIs due to these antimicrobial-resistant pathogens.
- [Show abstract] [Hide abstract] ABSTRACT: This report compares the clinical characteristics, epidemiologic investigations, infection-control evaluations, and microbiologic findings of all 7 of the cases of vancomycin-resistant Staphylococcus aureus (VRSA) infection in the United States during the period 2002-2006. Epidemiologic, clinical, and infection-control information was collected. VRSA isolates underwent confirmatory identification, antimicrobial susceptibility testing, pulsed-field gel electrophoresis, and typing of the resistance genes. To assess VRSA transmission, case patients and their contacts were screened for VRSA carriage. Seven cases were identified from 2002 through 2006; 5 were reported from Michigan, 1 was reported from Pennsylvania, and 1 was reported from New York. All VRSA isolates were vanA positive and had a median vancomycin minimum inhibitory concentration of 512 microg/mL. All case patients had a history of prior methicillin-resistant S. aureus and enterococcal infection or colonization; all had several underlying conditions, including chronic skin ulcers; and most had received vancomycin therapy prior to their VRSA infection. Person-to-person transmission of VRSA was not identified beyond any of the case patients. Infection-control precautions were evaluated and were consistent with established guidelines. Seven patients with vanA-positive VRSA have been identified in the United States. Prompt detection by microbiology laboratories and adherence to recommended infection control measures for multidrug-resistant organisms appear to have prevented transmission to other patients.
- [Show abstract] [Hide abstract] ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) infections are often defined as healthcare-associated (HA) or community-associated (CA) based on three different classification schemes: healthcare risk factor, infection type, or susceptibility pattern. This dissertation analyzed the sensitivity, specificity, and utility of these classifications using MRSA case data from Michigan. MRSA infections were voluntarily reported to the Michigan Department of Community Health (MDCH) from October 2004 through December 2005. Data on patient demographics, risk factors, and infection information were recorded on the MDCH MRSA Report Form and submitted with laboratory susceptibility test results. A total of 2,151 non-duplicate MRSA infections were reported. Pulsed-field gel electrophoresis (PFGE) tests were conducted on 244 randomly selected isolates from reported cases. The first project classified MRSA infections as HA or CA using each of the three classification schemes, then examined results for inconsistency across methods. Comparison of HA and CA results using the common classification schemes revealed a large proportion of inconsistent results. The second project used PFGE test result as a gold standard to consider the three classification schemes and other important contributing variables aimed at producing an improved multivariable classification model. This new model using infection type, susceptibility pattern, age and hospitalized as variables better predicted PFGE classification of HA or CA than any other single classification method. The third project evaluated accuracy of the new classification model and used it to define the epidemiology of Michigan MRSA infections. This analysis revealed that MRSA is prevalent across Michigan and CA-MRSA, particularly among males, blacks, people within correctional facilities, and people presenting to emergency departments. A final project produced a comprehensive review of the first seven cases of emergent vancomycin-resistant Staphylococcus aureus (VRSA) in the US. All VRSA cases had a history of prior MRSA and enterococcal infection or colonization; all had several underlying conditions and most had received vancomycin prior to their VRSA infection. In conclusion, the improved method to categorize MRSA infections as HA or CA, and characterization of the VRSA cases, provides new knowledge that will help to accurately target control efforts and prevention methods and messages to better combat this adept and evolving bacterium.
- [Show abstract] [Hide abstract] ABSTRACT: During the 2003-04 influenza season, 17 cases of Staphylococcus aureus community-acquired pneumonia (CAP) were reported from 9 states; 15 (88%) were associated with methicillin-resistant S. aureus (MRSA). The median age of patients was 21 years; 5 (29%) had underlying diseases, and 4 (24%) had risk factors for MRSA. Twelve (71%) had laboratory evidence of influenza virus infection. All but 1 patient, who died on arrival, were hospitalized. Death occurred in 5 (4 with MRSA). S. aureus isolates were available from 13 (76%) patients (11 MRSA). Toxin genes were detected in all isolates; 11 (85%) had only genes for Panton-Valentine leukocidin. All isolates had community-associated pulsed-field gel electrophoresis patterns; all MRSA isolates had the staphylococcal cassette chromosome mec type IVa. In communities with a high prevalence of MRSA, empiric therapy of severe CAP during periods of high influenza activity should include consideration for MRSA.
Centers for Disease Control and Prevention
Атланта, Michigan, United States
- Division of Healthcare Quality Promotion
University of MichiganAnn Arbor, Michigan, United States
MDCH Michigan Department of Community HealthMichigan Center, Michigan, United States
Wayne State UniversityDetroit, Michigan, United States
Detroit Medical CenterDetroit, Michigan, United States