Active Surveillance and Contact Precautions for Preventing Methicillin-Resistant Staphylococcus aureus Healthcare-Associated Infections During the COVID-19 Pandemic.

BACKGROUND: Statistically significant decreases in methicillin-resistant Staphylococcus aureus (MRSA) healthcare-associated infections (HAIs) occurred in Veterans Affairs (VA) hospitals from 2007 to 2019 using a national policy of active surveillance (AS) for facility admissions and contact precautions for MRSA colonized (CPC) or infected (CPI) patients, but the impact of suspending these measures to free up laboratory resources for testing and conserve personal protective equipment for coronavirus disease 2019 (COVID-19) on MRSA HAI rates is not known. METHODS: From July 2020 to June 2022 all 123 acute care VA hospitals nationwide were given the rolling option to suspend (or re-initiate) any combination of AS, CPC, or CPI each month, and MRSA HAIs in intensive care units (ICUs) and non-ICUs were tracked. RESULTS: There were 917 591 admissions, 5 225 174 patient-days, and 568 MRSA HAIs. The MRSA HAI rate/1000 patient-days in ICUs was 0.20 (95% confidence interval [CI], .15-.26) for facilities practicing "AS + CPC + CPI" compared to 0.65 (95% CI, .41-.98; P < .001) for those not practicing any of these strategies, and in non-ICUs was 0.07 (95% CI, .05-.08) and 0.12 (95% CI, .08-.19; P = .01) for the respective policies. Accounting for monthly COVID-19 facility admissions using a negative binomial regression model did not change the relationships between facility policy and MRSA HAI rates. There was no significant difference in monthly facility urinary catheter-associated infection rates, a non-equivalent dependent variable, in the policy categories in either ICUs or non-ICUs. CONCLUSIONS: Facility removal of MRSA prevention practices was associated with higher rates of MRSA HAIs in ICUs and non-ICUs.

Epidemiology and outcomes associated with carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant Pseudomonas aeruginosa: a retrospective cohort study.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) are a growing threat. The objective of this study was to describe CRAB and CRPA epidemiology and identify factors associated with mortality and length of stay (LOS) post-culture. METHODS: This was a national retrospective cohort study of Veterans with CRAB or CRPA positive cultures from 2013 to 2018, conducted at Hines Veterans Affairs Hospital. Carbapenem resistance was defined as non-susceptibility to imipenem, meropenem and/or doripenem. Multivariable cluster adjusted regression models were fit to assess the association of post-culture LOS among inpatient and long-term care (LTC) and to identify factors associated with 90-day and 365-day mortality after positive CRAB and CRPA cultures. RESULTS: CRAB and CRPA were identified in 1,048 and 8,204 unique patients respectively, with 90-day mortality rates of 30.3% and 24.5% and inpatient post-LOS of 26 and 27 days. Positive blood cultures were associated with an increased odds of 90-day mortality compared to urine cultures in patients with CRAB (OR 6.98, 95% CI 3.55-13.73) and CRPA (OR 2.82, 95% CI 2.04-3.90). In patients with CRAB and CRPA blood cultures, higher Charlson score was associated with increased odds of 90-day mortality. In CRAB and CRPA, among patients from inpatient care settings, blood cultures were associated with a decreased LOS compared to urine cultures. CONCLUSIONS: Positive blood cultures and more comorbidities were associated with higher odds for mortality in patients with CRAB and CRPA. Recognizing these factors would encourage clinicians to treat these patients in a timely manner to improve outcomes of patients infected with these organisms.

Expanding an Economic Evaluation of the Veterans Affairs (VA) Methicillin-resistant Staphylococcus aureus (MRSA) Prevention Initiative to Include Prevention of Infections From Other Pathogens.

BACKGROUND: In October 2007, Veterans Affairs (VA) launched a nationwide effort to reduce methicillin-resistant Staphylococcus aureus (MRSA) transmission called the National MRSA Prevention Initiative. Although the initiative focused on MRSA, recent evidence suggests that it also led to a significant decrease in hospital-onset (HO) gram-negative rod (GNR) bacteremia, vancomycin-resistant Enterococci (VRE), and Clostridioides difficile infections. The objective of this analysis was to evaluate the cost-effectiveness and the budget impact of the initiative taking into account MRSA, GNR, VRE, and C. difficile infections. METHODS: We developed an economic model using published data on the rate of MRSA hospital-acquired infections (HAIs) and HO-GNR bacteremia in the VA from October 2007 to September 2015, estimates of the attributable cost and mortality of these infections, and the costs associated with the intervention obtained through a microcosting approach. We explored several different assumptions for the rate of infections that would have occurred if the initiative had not been implemented. Effectiveness was measured in life-years (LYs) gained. RESULTS: We found that during fiscal years 2008-2015, the initiative resulted in an estimated 4761-9236 fewer MRSA HAIs, 1447-2159 fewer HO-GNR bacteremia, 3083-3602 fewer C. difficile infections, and 2075-5393 fewer VRE infections. The initiative itself was estimated to cost $561 million over this 8-year period, whereas the cost savings from prevented MRSA HAIs ranged from $165 to $315 million and from prevented HO-GNR bacteremia, CRE and C. difficile infections ranged from $174 to $200 million. The incremental cost-effectiveness of the initiative ranged from $12 146 to $38 673/LY when just including MRSA HAIs and from $1354 to $4369/LY when including the additional pathogens. The overall impact on the VA's budget ranged from $67 to$195 million. CONCLUSIONS: An MRSA surveillance and prevention strategy in VA may have prevented a substantial number of infections from MRSA and other organisms. The net increase in cost from implementing this strategy was quite small when considering infections from all types of organisms. Including spillover effects of organism-specific prevention efforts onto other organisms can provide a more comprehensive evaluation of the costs and benefits of these interventions.

Methicillin-resistant Staphylococcus aureus Colonization and Pre- and Post-hospital Discharge Infection Risk.

Background: The Department of Veterans Affairs implemented an active surveillance program for methicillin-resistant Staphylococcus aureus (MRSA) in 2007 in which acute care inpatients are tested for MRSA carriage on admission, unit-to-unit transfer, and discharge. Using these data, we followed patients longitudinally to estimate the difference in infection rates for those who were not colonized, those who were colonized on admission (importers), and those who acquired MRSA during their stay. We examined MRSA infections that occurred prior to discharge and at 30, 90, 180, and 365 days after discharge. Methods: We constructed a dataset of 985626 first admissions from January 2008 through December 2015 who had surveillance tests performed for MRSA carriage. We performed multivariable Cox proportional hazards and logistic regression models to examine the relationship between MRSA colonization status and infection. Results: The MRSA infection rate across the predischarge and 180-day postdischarge time period was 5.5% in importers and 7.0% in acquirers without a direct admission to the intensive care unit (ICU) and 11.4% in importers and 11.7% in acquirers who were admitted directly to the ICU. The predischarge hazard ratio for MRSA infection was 29.6 (95% confidence interval [CI], 26.5-32.9) for importers and 28.8 (95% CI, 23.5-35.3) for acquirers compared to those not colonized. Fully 63.9% of all MRSA pre- and postdischarge infections among importers and 61.2% among acquirers occurred within 180 days after discharge. Conclusions: MRSA colonization significantly increases the risk of subsequent MRSA infection. In addition, a substantial proportion of MRSA infections occur after discharge from the hospital.

Vital Signs: Trends in Staphylococcus aureus Infections in Veterans Affairs Medical Centers - United States, 2005-2017.

INTRODUCTION: By 2007, all Department of Veterans Affairs medical centers (VAMCs) had initiated a multifaceted methicillin-resistant Staphylococcus aureus (MRSA) prevention program. MRSA and methicillin-susceptible S. aureus (MSSA) infection rates among VAMC inpatients from 2005 to 2017 were assessed. METHODS: Clinical microbiology data from any patient admitted to an acute-care VAMC in the United States from 2005 through 2017 and trends in hospital-acquired MRSA colonization were examined. RESULTS: S. aureus infections decreased by 43% overall during the study period (p<0.001), driven primarily by decreases in MRSA, which decreased by 55% (p<0.001), whereas MSSA decreased by 12% (p = 0.003). Hospital-onset MRSA and MSSA infections decreased by 66% (p<0.001) and 19% (p = 0.02), respectively. Community-onset MRSA infections decreased by 41% (p<0.001), whereas MSSA infections showed no significant decline. Acquisition of MRSA colonization decreased 78% during 2008-2017 (17% annually, p<0.001). MRSA infection rates declined more sharply among patients who had negative admission surveillance MRSA screening tests (annual 9.7% decline) compared with those among patients with positive admission MRSA screening tests (4.2%) (p<0.05). CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Significant reductions in S. aureus infection following the VAMC intervention were led primarily by decreases in MRSA. Moreover, MRSA infection declines were much larger among patients not carrying MRSA at the time of admission than among those who were. Taken together, these results suggest that decreased MRSA transmission played a substantial role in reducing overall S. aureus infections at VAMCs. Recent calls to withdraw infection control interventions designed to prevent MRSA transmission might be premature and inadvisable, at least until more is known about effective control of bacterial pathogen transmission in health care settings. Effective S. aureus prevention strategies require a multifaceted approach that includes adherence to current CDC recommendations for preventing not only device- and procedure-associated infections, but also transmission of health care-prevalent strains.

The Effect of a Nationwide Infection Control Program Expansion on Hospital-Onset Gram-Negative Rod Bacteremia in 130 Veterans Health Administration Medical Centers: An Interrupted Time-Series Analysis.

BACKGROUND: The Veterans Health Administration (VHA) introduced the Methicillin-Resistant Staphylococcus aureus (MRSA) Prevention Initiative in March 2007. Although the initiative has been perceived as a vertical intervention focusing on MRSA, it also expanded infection prevention and control programs and resources. We aimed to assess the horizontal effect of the initiative on hospital-onset (HO) gram-negative rod (GNR) bacteremia. METHODS: This retrospective cohort included all patients who had HO bacteremia due to Escherichia coli, Klebsiella species, or Pseudomonas aeruginosa at 130 VHA facilities from January 2003 to December 2013. The effects were assessed using segmented linear regression with autoregressive error models, incorporating autocorrelation, immediate effect, and time before and after the initiative. Community-acquired (CA) bacteremia with same species was also analyzed as nonequivalent dependent controls. RESULTS: A total of 11 196 patients experienced HO-GNR bacteremia during the study period. There was a significant change of slope in HO-GNR bacteremia incidence rates from before the initiative (+0.3%/month) to after (-0.4%/month) (P < .01), while CA GNR incidence rates did not significantly change (P = .08). Cumulative effect of the intervention on HO-GNR bacteremia incidence rates at the end of the study period was estimated to be -43.2% (95% confidence interval, -51.6% to -32.4%). Similar effects were observed in subgroup analyses of each species and antimicrobial susceptibility profile. CONCLUSIONS: Within 130 VHA facilities, there was a sustained decline in HO-GNR bacteremia incidence rates after the implementation of the MRSA Prevention Initiative. As these organisms were not specifically targeted, it is likely that horizontal components of the initiative contributed to this decline.

Veterans Affairs initiative to prevent methicillin-resistant Staphylococcus aureus infections.

BACKGROUND: Health care-associated infections with methicillin-resistant Staphylococcus aureus (MRSA) have been an increasing concern in Veterans Affairs (VA) hospitals. METHODS: A "MRSA bundle" was implemented in 2007 in acute care VA hospitals nationwide in an effort to decrease health care-associated infections with MRSA. The bundle consisted of universal nasal surveillance for MRSA, contact precautions for patients colonized or infected with MRSA, hand hygiene, and a change in the institutional culture whereby infection control would become the responsibility of everyone who had contact with patients. Each month, personnel at each facility entered into a central database aggregate data on adherence to surveillance practice, the prevalence of MRSA colonization or infection, and health care-associated transmissions of and infections with MRSA. We assessed the effect of the MRSA bundle on health care-associated MRSA infections. RESULTS: From October 2007, when the bundle was fully implemented, through June 2010, there were 1,934,598 admissions to or transfers or discharges from intensive care units (ICUs) and non-ICUs (ICUs, 365,139; non-ICUs, 1,569,459) and 8,318,675 patient-days (ICUs, 1,312,840; and non-ICUs, 7,005,835). During this period, the percentage of patients who were screened at admission increased from 82% to 96%, and the percentage who were screened at transfer or discharge increased from 72% to 93%. The mean (±SD) prevalence of MRSA colonization or infection at the time of hospital admission was 13.6±3.7%. The rates of health care-associated MRSA infections in ICUs had not changed in the 2 years before October 2007 (P=0.50 for trend) but declined with implementation of the bundle, from 1.64 infections per 1000 patient-days in October 2007 to 0.62 per 1000 patient-days in June 2010, a decrease of 62% (P<0.001 for trend). During this same period, the rates of health care-associated MRSA infections in non-ICUs fell from 0.47 per 1000 patient-days to 0.26 per 1000 patient-days, a decrease of 45% (P<0.001 for trend). CONCLUSIONS: A program of universal surveillance, contact precautions, hand hygiene, and institutional culture change was associated with a decrease in health care-associated transmissions of and infections with MRSA in a large health care system.

Facility- and patient-level factors associated with implementation of contact precautions in hospitalized VA patients with positive CRE cultures.

Decreasing the time to contact precautions (CP) is critical to carbapenem-resistant Enterobacterales (CRE) prevention. Identifying factors associated with delayed CP can decrease the spread from patients with CRE. In this study, a shorter length of stay was associated with being placed in CP within 3 days.

Development and implementation of a nationwide multidrug-resistant organism tracking and alert system for Veterans Affairs medical centers.

OBJECTIVE: Develop and implement a system in the Veterans Health Administration (VA) to alert local medical center personnel in real time when an acute- or long-term care patient/resident is admitted to their facility with a history of colonization or infection with a multidrug-resistant organism (MDRO) previously identified at any VA facility across the nation. METHODS: An algorithm was developed to extract clinical microbiology and local facility census data from the VA Corporate Data Warehouse initially targeting carbapenem-resistant Enterobacterales (CRE) and methicillin-resistant Staphylococcus aureus (MRSA). The algorithm was validated with chart review of CRE cases from 2010-2018, trialed and refined in 24 VA healthcare systems over two years, expanded to other MDROs and implemented nationwide on 4/2022 as "VA Bug Alert" (VABA). Use through 8/2023 was assessed. RESULTS: VABA performed well for CRE with recall of 96.3%, precision of 99.8%, and F1 score of 98.0%. At the 24 trial sites, feedback was recorded for 1,011 admissions with a history of CRE (130), MRSA (814), or both (67). Among Infection Preventionists and MDRO Prevention Coordinators, 338 (33%) reported being previously unaware of the information, and of these, 271 (80%) reported they would not have otherwise known this information. By fourteen months after nationwide implementation, 113/130 (87%) VA healthcare systems had at least one VABA subscriber. CONCLUSIONS: A national system for alerting facilities in real-time of patients admitted with an MDRO history was successfully developed and implemented in VA. Next steps include understanding facilitators and barriers to use and coordination with non-VA facilities nationwide.

Lack of correlation between standardized antimicrobial administration ratios (SAARs) and healthcare-facility-onset Clostridioides difficile infection rates in Veterans Affairs medical facilities.

We detected no correlation between standardized antimicrobial administration ratios (SAARs) and healthcare facility-onset Clostridioides difficile infection (HO-CDI) rates in 102 acute-care Veterans Affairs medical centers over 16 months. SAARs may be useful for investigating trends in local antimicrobial use, but no ratio threshold demarcated HO-CDI risk.

Treatment effectiveness of antibiotic therapy in Veterans with multidrug-resistant Acinetobacter spp. bacteremia.

Objective: To describe antimicrobial therapy used for multidrug-resistant (MDR) Acinetobacter spp. bacteremia in Veterans and impacts on mortality. Methods: This was a retrospective cohort study of hospitalized Veterans Affairs patients from 2012 to 2018 with a positive MDR Acinetobacter spp. blood culture who received antimicrobial treatment 2 days prior to through 5 days after the culture date. Only the first culture per patient was used. The association between treatment and patient characteristics was assessed using bivariate analyses. Multivariable logistic regression models examined the relationship between antibiotic regimen and in-hospital, 30-day, and 1-year mortality. Generalized linear models were used to assess cost outcomes. Results: MDR Acinetobacter spp. was identified in 184 patients. Most cultures identified were Acinetobacter baumannii (90%), 3% were Acinetobacter lwoffii, and 7% were other Acinetobacter species. Penicillins-ß-lactamase inhibitor combinations (51.1%) and carbapenems (51.6%)-were the most prescribed antibiotics. In unadjusted analysis, extended spectrum cephalosporins and penicillins-ß-lactamase inhibitor combinations-were associated with a decreased odds of 30-day mortality but were insignificant after adjustment (adjusted odds ratio (aOR) = 0.47, 95% CI, 0.21-1.05, aOR = 0.75, 95% CI, 0.37-1.53). There was no association between combination therapy vs monotherapy and 30-day mortality (aOR = 1.55, 95% CI, 0.72-3.32). Conclusion: In hospitalized Veterans with MDR Acinetobacter spp., none of the treatments were shown to be associated with in-hospital, 30-day, and 1-year mortality. Combination therapy was not associated with decreased mortality for MDR Acinetobacter spp. bacteremia.

Healthcare-associated infections in Veterans Affairs acute-care and long-term healthcare facilities during the coronavirus disease 2019 (COVID-19) pandemic.

OBJECTIVE: To assess the impact of the coronavirus disease 2019 (COVID-19) pandemic on healthcare-associated infections (HAIs) reported from 128 acute-care and 132 long-term care Veterans Affairs (VA) facilities. METHODS: We compared central-line-associated bloodstream infections (CLABSIs), ventilator-associated events (VAEs), catheter-associated urinary tract infections (CAUTIs), methicillin-resistant Staphylococcus aureus (MRSA), and Clostridioides difficile infections and rates reported from each facility monthly to a centralized database before the pandemic (February 2019 through January 2020) and during the pandemic (July 2020 through June 2021). RESULTS: Nationwide VA COVID-19 admissions peaked in January 2021. Significant increases in the rates of CLABSIs, VAEs, and MRSA all-site HAIs (but not MRSA CLABSIs) were observed during the pandemic in acute-care facilities. There was no significant change in CAUTI rates, and C. difficile rates significantly decreased. There were no significant increases in HAIs in long-term care facilities. CONCLUSIONS: The COVID-19 pandemic had a differential impact on HAIs of various types in VA acute care, with many rates increasing. The decrease in CDI HAIs may be due, in part, to evolving diagnostic testing. The minimal impact of COVID-19 in VA long-term facilities may reflect differences in patient numbers and acuity and early recognition of the impact of the pandemic on nursing home residents leading to increased vigilance and optimization of infection prevention and control practices in that setting. These data support the need for building and sustaining conventional infection prevention and control strategies before and during a pandemic.

Hospital coronavirus disease 2019 (COVID-19) public health reporting: Lessons from validation of an automated surveillance tool to facilitate data collection.

A comparison of computer-extracted and facility-reported counts of hospitalized coronavirus disease 2019 (COVID-19) patients for public health reporting at 36 hospitals revealed 42% of days with matching counts between the data sources. Miscategorization of suspect cases was a primary driver of discordance. Clear reporting definitions and data validation facilitate emerging disease surveillance.

Association between Clostridioides difficile infection testing results and decision to treat.

We sought to determine how often patients with a negative toxin enzyme immunoassay following a positive nucleic acid amplification test for Clostridioides difficile infection (CDI) were treated for CDI in Veterans Affairs facilities. From October 2018 through March 2021, 702 (29.5%) of 2,374 unique patients with these test results were treated.

Infectious Disease Consults of Pseudomonas aeruginosa Bloodstream Infection and Impact on Health Outcomes.

Background: Infectious diseases (ID) consultation improves health outcomes for certain infections but has not been well described for Pseudomonas aeruginosa (PA) bloodstream infection (BSI). Therefore, the goal of this study was to examine ID consultation of inpatients with PA BSI and factors impacting outcomes. Methods: This was a retrospective cohort study from January 1, 2012, to December 31, 2018, of adult hospitalized veterans with PA BSI and antibiotic treatment 2 days before through 5 days after the culture date. Multidrug-resistant (MDR) cultures were defined as cultures with resistance to at least 1 agent in ≥3 antimicrobial categories tested. Multivariable logistic regression models were fit to assess the impact of ID consults and adequate treatment on mortality. Results: A total of 3256 patients had PA BSI, of whom 367 (11.3%) were multidrug resistant (MDR). Most were male (97.5%), over 65 years old (71.2%), and White (70.9%). Nearly one-fourth (n = 784, 23.3%) died during hospitalization, and 870 (25.8%) died within 30 days of their culture. Adjusted models showed that ID consultation was associated with decreased in-hospital (odds ratio [OR], 0.47; 95% CI, 0.39-0.56) and 30-day mortality (OR, 0.51; 95% CI, 0.42-0.62). Conclusions: Consultation with ID physicians improves clinical outcomes such as in-hospital and 30-day mortality for patients with PA BSI. ID consultation provides value and should be considered for patients with PA BSI.

Effect of testing methods on incidence of Clostridioides difficile infection rates in Veterans' Affairs medical centers.

Clostridioidesdifficile infection rates from 7 facilities that used nucleic acid amplification testing (NAAT) alone for 12 months then switched to NAAT plus toxin enzyme immunoassay (EIA) and reported the latter result for 12 months were compared to 70 facilities that used NAAT alone for all 24 months. There was no significant difference in rates between facility groups over the first 12 months (P = .21, linear regression), but we detected a decrease in rates for the facilities that changed to NAAT+EIA (P < .0001).

Carbapenem-resistant Enterobacteriaceae epidemiology in Veterans' Affairs medical centers varies by facility characteristics.

This is an epidemiological study of carbapenem-resistant Enterobacteriaceae (CRE) in Veterans' Affairs medical centers (VAMCs). In 2017, almost 75% of VAMCs had at least 1 CRE case. We observed substantial geographic variability, with more cases in urban, complex facilities. This supports the benefit of tailoring infection control strategies to facility characteristics.

A targeted assessment for prevention strategy to decrease Clostridioides difficile infections in Veterans Affairs acute-care medical centers.

OBJECTIVE: A guideline for the prevention of Clostridioides difficile infection (CDI) in 127 Veterans Health Administration acute-care facilities was implemented in July 2012. Beginning in 2015, a targeted assessment for prevention strategy was used to evaluate facilities for hospital-onset healthcare-facility-associated CDIs to focus prevention efforts where they might have the most impact in reaching a reduction goal of 30% nationwide. METHODS: We calculated standardized infection ratios (SIRs) and cumulative attributable differences (CADs) using a national data baseline. Facilities were ranked by CAD, and those with the 10 highest CAD values were targeted for periodic conference calls or a site visit from January 2016-September 2019. RESULTS: The hospital-onset healthcare-facility-associated CDI rate in the 10 facilities with the highest CADs declined 56% during the process improvement period, compared to a 44% decline in the 117 nonintervention facilities (P = .03). CONCLUSION: Process improvement interventions targeting facilities ranked by CAD values may be an efficient strategy for decreasing CDI rates in a large healthcare system.