To estimate the relative risk (RR) of developing methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) colonization or infection within 30 days of ambulance transport.

We performed a retrospective cohort study of patients with a principal diagnosis of chest pain presenting to our emergency department (ED) over a 4-year period. Patients were included if they presented from and were discharged to nonhealthcare locations without being admitted. Encounters were stratified by arrival mechanism: ambulance versus private vehicle. We performed propensity score matching and multivariable logistic regression to estimate the RR for the primary outcome.

In total, 321,229 patients had ED encounters during the study period. After applying inclusion criteria and propensity score matching, there were 11,324 patients: 3,903 in the ambulance group and 7,421 in the unexposed group. Among them, 12 patients (0.11%) had the outcome of interest, including 9 (0.08%) with MRSA and 3 (0.03%) with VRE. The 30-day prevalence of MRSA or VRE was larger in the ambulance group than in the unexposed group: 8 (0.20%) and 4 (0.05%), respectively (P = .02). Patients who presented to the ED via ambulance were almost 4 times more likely to have MRSA or VRE within 30 days of their encounter (RR, 3.72; 95% CI, 1.09–12.71; P = .04).

Our cohort study is the first to demonstrate an association between ambulance exposure and pathogen incidence, representing the first step in evaluating medical-transport–associated infection burden to eventually develop interventions to address it.

To evaluate the cost of 1-stage and 2-stage revisions, debridement, antibiotic and implant retention (DAIR) and DAIR with liner exchange for complex surgical site infections (SSIs) following hip and knee replacements.

Retrospective population-based economic analysis of patients undergoing intervention for SSIs between April 1, 2012 and March 31, 2019.

The study was conducted in the Calgary zone of Alberta Health Services (AHS) in Canada.

Individuals >18 years with complex SSI following hip or knee replacement.

Patients with complex SSIs were identified using the AHS infection prevention and control database. A combination of microcosting and gross costing methods were used to estimate 12- and 24-month costs following the initial hospital admission for arthroplasty. Subgroup, inverse Gaussian and γ regression analyses were used to evaluate the impact of age and comorbidities on cost.

In total, 142 patients with complex SSIs were identified, with a mean age of 66.8 years. Total direct medical costs in United States dollars of 2-stage revisions were ($100,992 (95% CI, 34,587–167,396) at 12 months. The 1-stage revision ($41,176; 95% CI, 23,361–58,991), DAIR with liner exchange ($41,267; 95% CI, 29,923–52,612) and DAIR ($46,605; 95% CI, 15,277–76,844) were associated with fewer costs at 12 months. Age >65 years and chronic complications of diabetes and hypertension were associated with increased costs in subgroup and regression analysis.

Medical costs are highest at 12 months and for 2-stage revisions in hip and knee complex SSI cases. Further work should explore surgical outcomes correlated with costs to enhance patient care.

We observed an overall increase in the use of third- and fourth-generation cephalosporins after fluoroquinolone preauthorization was implemented. We examined the change in specific third- and fourth-generation cephalosporin use, and we sought to determine whether there was a consequent change in non-susceptibility of select Gram-negative bacterial isolates to these antibiotics.

Retrospective quasi-experimental study.

Academic hospital.

Fluoroquinolone preauthorization was implemented in the hospital in October 2005. We used interrupted time series (ITS) Poisson regression models to examine trends in monthly rates of ceftriaxone, ceftazidime, and cefepime use and trends in yearly rates of nonsusceptible isolates (NSIs) of select Gram-negative bacteria before (1998–2004) and after (2006–2016) fluoroquinolone preauthorization was implemented.

Rates of use of ceftriaxone and cefepime increased after fluoroquinolone preauthorization was implemented (ceftriaxone RR, 1.002; 95% CI, 1.002–1.003; P < .0001; cefepime RR, 1.003; 95% CI, 1.001–1.004; P = .0006), but ceftazidime use continued to decline (RR, 0.991, 95% CI, 0.990–0.992; P < .0001). Rates of ceftazidime and cefepime NSIs of Pseudomonas aeruginosa (ceftazidime RR, 0.937; 95% CI, 0.910–0.965, P < .0001; cefepime RR, 0.937; 95% CI, 0.912–0.963; P < .0001) declined after fluoroquinolone preauthorization was implemented. Rates of ceftazidime and cefepime NSIs of Enterobacter cloacae (ceftazidime RR, 1.116; 95% CI, 1.078–1.154; P < .0001; cefepime RR, 1.198; 95% CI, 1.112–1.291; P < .0001) and cefepime NSI of Acinetobacter baumannii (RR, 1.169; 95% CI, 1.081–1.263; P < .0001) were increasing before fluoroquinolone preauthorization was implemented but became stable thereafter: E. cloacae (ceftazidime RR, 0.987; 95% CI, 0.948–1.028; P = .531; cefepime RR, 0.990; 95% CI, 0.962–1.018; P = .461) and A. baumannii (cefepime RR, 0.972; 95% CI, 0.939–1.006; P = .100).

Fluoroquinolone preauthorization may increase use of unrestricted third- and fourth-generation cephalosporins; however, we did not observe increased antimicrobial resistance to these agents, especially among clinically important Gram-negative bacteria known for hospital-acquired infections.

We investigated the quality of life (QoL) of patients hospitalized with C. difficile infection (CDI).

Prospective survey study.

US tertiary-care referral center, acute-care setting.

Adults hospitalized with a diagnosis of CDI, defined as ≥3 episodes of unformed stool in 24 hours and a positive laboratory test for C. difficile.

We surveyed patients from July 2019 to March 2020 using the disease-specific Cdiff32 questionnaire and the generic PROMIS GH survey. We compared differences in Cdiff32 scores among demographic and clinical subgroups (including CDI severity, CDI recurrence, and various comorbidities) using 2-sample t tests. We compared PROMIS GH scores to the general population T score of 50 using 1-sample t tests. We performed multivariable linear regression to identify predictors of Cdiff32 scores.

In total, 100 inpatients (mean age, 58.6 ±17.1 years; 53.0% male; 87.0% white) diagnosed with CDI completed QoL surveys. PROMIS GH physical health summary scores (T = 37.3; P < .001) and mental health summary scores (T = 43.4; P < .001) were significantly lower than those of the general population. In bivariate analysis, recurrent CDI, severe CDI, and number of stools were associated with lower Cdiff32 scores. In multivariable linear regression, recurrent CDI, severe CDI, and each additional stool in the previous 24 hours were associated with significantly decreased Cdiff32 scores.

Patients hospitalized with CDI reported low scores on the Cdiff32 and PROMIS GH, demonstrating a negative impact of CDI on QoL in multiple health domains. The Cdiff32 questionnaire is particularly sensitive to QoL changes in patients with recurrent or severe disease.

The coronavirus disease 2019 (COVID-19) pandemic has had a considerable impact on US hospitalizations, affecting processes and patient population.

To evaluate the impact of COVID-19 pandemic on central-line–associated bloodstream infections (CLABSIs) and catheter associated urinary tract infections (CAUTIs) in hospitals.

We performed a retrospective study of CLABSIs and CAUTIs in 78 US 12 months before COVID-19 and 6 months during COVID-19 pandemic.

During the 2 study periods, there were 795,022 central-line days and 817,267 urinary catheter days. Compared to the period before the COVID-19 pandemic, CLABSI rates increased by 51.0% during the pandemic period from 0.56 to 0.85 per 1,000 line days (P < .001) and by 62.9% from 1.00 to 1.64 per 10,000 patient days (P < .001). Hospitals with monthly COVID-19 patients representing >10% of admissions had a National Health Safety Network (NHSN) device standardized infection ratio for CLABSI that was 2.38 times higher than hospitals with <5% prevalence during the pandemic period (P = .004). Coagulase-negative Staphylococcus CLABSIs increased by 130% from 0.07 to 0.17 events per 1,000 line days (P < .001), and Candida spp by 56.9% from 0.14 to 0.21 per 1,000 line days (P = .01). In contrast, no significant changes were identified for CAUTI (0.86 vs 0.77 per 1,000 catheter days; P = .19).

The COVID-19 pandemic was associated with substantial increases in CLABSIs but not CAUTIs. Our findings underscore the importance of hardwiring processes for optimal line care and regular feedback on performance to maintain a safe environment.

To determine the impact of various aerosol mitigation interventions and to establish duration of aerosol persistence in a variety of dental clinic configurations.

We performed aerosol measurement studies in endodontic, orthodontic, periodontic, pediatric, and general dentistry clinics. We used an optical aerosol spectrometer and wearable particulate matter sensors to measure real-time aerosol concentration from the vantage point of the dentist during routine care in a variety of clinic configurations (eg, open bay, single room, partitioned operatories). We compared the impact of aerosol mitigation strategies (eg, ventilation and high-volume evacuation (HVE), and prevalence of particulate matter) in the dental clinic environment before, during, and after high-speed drilling, slow–speed drilling, and ultrasonic scaling procedures.

Conical and ISOVAC HVE were superior to standard-tip evacuation for aerosol-generating procedures. When aerosols were detected in the environment, they were rapidly dispersed within minutes of completing the aerosol-generating procedure. Few aerosols were detected in dental clinics, regardless of configuration, when conical and ISOVAC HVE were used.

Dentists should consider using conical or ISOVAC HVE rather than standard-tip evacuators to reduce aerosols generated during routine clinical practice. Furthermore, when such effective aerosol mitigation strategies are employed, dentists need not leave dental chairs fallow between patients because aerosols are rapidly dispersed.

To determine prophylaxis appropriateness by Veterans’ Affairs (VA) dentists.

A cross-sectional study of dental visits, 2015–2019.

Antibiotics within 7 days before a visit in the absence of an oral infection were included. Appropriate antibiotic prophylaxis was defined as visits with gingival manipulation and further delineated into narrow and broad definitions based on comorbidities. The primary analysis applied a narrow definition of appropriate prophylaxis: cardiac conditions at the highest risk of an adverse outcome from endocarditis. The secondary analysis included a broader definition: cardiac or immunocompromising condition or tooth extractions and/or implants. Multivariable log-linear Poisson generalized estimating equation regression was used to assess the association between covariates and unnecessary prophylaxis prescriptions.

In total, 358,078 visits were associated with 369,102 antibiotics. The median prescription duration was 7 days (IQR, 7–10); only 6.5% were prescribed for 1 day. With the narrow definition, 15% of prophylaxis prescriptions were appropriate, which increased to 72% with the broader definition. Prophylaxis inconsistent with guidelines increased over time. For the narrow definition, Black (vs White) race, Latine (vs non-Latine) ethnicity, and visits located in the West census region were associated with unnecessary prophylaxis. Variables associated with a lower risk were older age, prosthetic joints, immunocompromising condition, and rural location.

Of every 6 antibiotic prophylaxis prescriptions, 5 were inconsistent with guidelines. Improving prophylaxis appropriateness and shortening duration may have substantial implications for stewardship. Guidelines should state whether antibiotic prophylaxis is indicated for extractions, implants, and immunocompromised patients.

Understanding the cognitive determinants of healthcare worker (HCW) behavior is important for improving the use of infection prevention and control (IPC) practices. Given a patient requiring only standard precautions, we examined the dimensions along which different populations of HCWs cognitively organize patient care tasks (ie, their mental models).

HCWs read a description of a patient and then rated the similarities of 25 patient care tasks from an infection prevention perspective. Using multidimensional scaling, we identified the dimensions (ie, characteristics of tasks) underlying these ratings and the salience of each dimension to HCWs.

Adult inpatient hospitals across an academic hospital network.

In total, 40 HCWs, comprising infection preventionists and nurses from intensive care units, emergency departments, and medical-surgical floors rated the similarity of tasks. To identify the meaning of each dimension, another 6 nurses rated each task in terms of specific characteristics of tasks.

Each HCW population perceived patient care tasks to vary along 3 common dimensions; most salient was the perceived magnitude of infection risk to the patient in a task, followed by the perceived dirtiness and risk of HCW exposure to body fluids, and lastly, the relative importance of a task for preventing versus controlling an infection in a patient.

For a patient requiring only standard precautions, different populations of HCWs have similar mental models of how various patient care tasks relate to IPC. Techniques for eliciting mental models open new avenues for understanding and ultimately modifying the cognitive determinants of IPC behaviors.

To measure the impact of exposure to patients using carbapenem on the acquisition of carbapenem-resistant gram-negative bacilli (CR-GNB) among patients not using carbapenems.

An ecological study and a cohort study.

Two medical surgical intensive care units (ICUs) in inner Brazil.

Patients admitted to 2 ICUs from 2013 through 2018 to whom carbapenem was not prescribed.

In the ecologic study, the monthly use of carbapenems (days of therapy [DOT] per 1,000 patient days) was tested for linear correlation with the 2-month moving average of incidence CR-GNB among patients to whom carbapenem was not prescribed. In the cohort study, those patients were addressed individually for risk factors (demographics, invasive interventions, use of antimicrobials) for acquisition of CR-GNB, including time at risk and the “carbapenem pressure,” described as the aggregate DOT among other ICU patients during time at risk. The analysis was performed in univariate and multivariable Poisson regression models.

The linear regression model revealed an association of total carbapenem use and incidence of CR-GNB (coefficient, 0.04; 95% confidence interval [CI], 0.02–0.06; P = .001). In the cohort model, the adjusted rate ratio (RR) for carbapenem DOT was 1.009 (95% CI, 1.001–1.018; P = .03). Other significant risk factors were mechanical ventilation and the previous use of ceftazidime (with or without avibactam).

Every additional DOT of total carbapenem use increased the risk of CR-GNB acquisition by patients not using carbapenems by nearly 1%. We found evidence for a population (“herd effect”-like) impact of antimicrobial use in the ICUs.

Assess the accumulation of protein and biofilm on the inner surfaces of new flexible gastroscope (FG) channels after 30 and 60 days of patient use and full reprocessing.

Clinical use study of biofilm accumulation in FG channels.

Endoscopy service of a public hospital.

First, we tested an FG in clinical use before the implementation of a revised reprocessing protocol (phase 1 baseline; n = 1). After replacement of the channels by new ones and the implementation of the protocol, 3 FGs were tested after 30 days of clinical use (phase 2; n = 3) and 3 FGs were tested after 60 days of clinical use (phase 3; n = 3), and the same FGs were tested in phase 2 and 3. Their biopsy, air, water, and air/water junction channels were removed and subjected to protein testing (n = 21), bacteriological culture (n = 21), and scanning electron microscopy (SEM) (n = 28). Air–water junction channels fragments were subjected to SEM only.

For the FGs, the average number of uses and reprocessing cycles was 60 times. Extensive biofilm was detected in air, water, and air–water junction channels (n = 18 of 28). All channels (28 of 28) showed residual matter, and structural damage was identified in most of them (20 of 28). Residual protein was detected in the air and water channels of all FG evaluated (phases 1–3), except for 1 air channel from phase 2. Bacteria were recovered from 8 of 21 channels, most air or water channels.

The short time before damage and biofilm accumulation in the channels was evident and suggests that improving the endoscope design is necessary. Better reprocessing methods and channel maintenance are needed.

The rapid spread of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) throughout key regions of the United States in early 2020 placed a premium on timely, national surveillance of hospital patient censuses. To meet that need, the Centers for Disease Control and Prevention’s National Healthcare Safety Network (NHSN), the nation’s largest hospital surveillance system, launched a module for collecting hospital coronavirus disease 2019 (COVID-19) data. We present time-series estimates of the critical hospital capacity indicators from April 1 to July 14, 2020.

From March 27 to July 14, 2020, the NHSN collected daily data on hospital bed occupancy, number of hospitalized patients with COVID-19, and the availability and/or use of mechanical ventilators. Time series were constructed using multiple imputation and survey weighting to allow near–real-time daily national and state estimates to be computed.

During the pandemic’s April peak in the United States, among an estimated 431,000 total inpatients, 84,000 (19%) had COVID-19. Although the number of inpatients with COVID-19 decreased from April to July, the proportion of occupied inpatient beds increased steadily. COVID-19 hospitalizations increased from mid-June in the South and Southwest regions after stay-at-home restrictions were eased. The proportion of inpatients with COVID-19 on ventilators decreased from April to July.

The NHSN hospital capacity estimates served as important, near–real-time indicators of the pandemic’s magnitude, spread, and impact, providing quantitative guidance for the public health response. Use of the estimates detected the rise of hospitalizations in specific geographic regions in June after they declined from a peak in April. Patient outcomes appeared to improve from early April to mid-July.

To evaluate the use of colorimetric indicators for monitoring ultraviolet-C (UV-C) light delivery to sites in patient rooms.

In laboratory testing, we examined the correlation between changes in color of 2 commercial colorimetric indicators and log10 reductions in methicillin-resistant Staphylococcus aureus (MRSA) and Clostridioides difficile spores with exposure to increasing doses of UV-C from a low-pressure mercury room decontamination device. In patient rooms, 1 of the colorimetric indicators was used to assess UV-C dose delivery to 27 sites in the room.

In laboratory testing, the manufacturer’s reference colors for MRSA and C. difficile reduction corresponded with doses of ∼10,000 and 46,000 µJ/cm2; these doses resulted in >3 log10 reductions in MRSA and C. difficile spores, respectively. In patient rooms, the colorimetric indicators demonstrated suboptimal delivery of UV-C dosing to shadowed areas, which was improved by providing cycles on each side of the patient bed rather than in a single position and altering device placement. Increasing duration of exposure increased the number of sites achieving adequate dosing to kill C. difficile spores.

Commercial colorimetric indicators provide rapid and easy-to-interpret information on the UV-C dose delivered to sites in patient rooms. The indicators may be useful for training environmental services personnel and optimizing the effectiveness of UV-C room decontamination devices.

To describe interfacility transfer communication (IFTC) methods for notification of multidrug-resistant organism (MDRO) status in a diverse sample of acute-care hospitals.

Cross-sectional survey.

Hospitals within the Society for Healthcare Epidemiology of America (SHEA) Research Network (SRN).

SRN members completed an electronic survey on protocols and methods for IFTC. We assessed differences in IFTC frequency, barriers, and perceived benefit by presence of an IFTC protocol.

Among 136 hospital representatives who were sent the survey, 54 (40%) responded, of whom 72% reported having an IFTC protocol in place. The presence of a protocol did not differ significantly by hospital size, academic affiliation, or international status. Of those with IFTC protocols, 44% reported consistent notification of MDRO status (>75% of the time) to receiving facilities, as opposed to 13% from those with no IFTC protocol (P = .04). Respondents from hospitals with IFTC protocols reported significantly fewer barriers to communication compared to those without (2.8 vs 4.3; P = .03). Overall, however, most respondents (56%) reported a lack of standardization in communication. Presence of an IFTC protocol did not affect whether respondents perceived IFTC protocols as having a significant impact on infection prevention or antimicrobial stewardship.

Most respondents reported having an IFTC protocol, which was associated with reduced communication barriers at transfer. Standardization of protocols and clarity about expectations for sending and receipt of information related to MDRO status may facilitate IFTC and promote appropriate and timely infection prevention practices.

Measuring the appropriateness of antibiotic prescribing in nursing homes remains a challenge. The revised McGeer criteria, which are widely used to conduct infection surveillance in nursing homes, were not designed to assess antibiotic appropriateness. The Loeb criteria were explicitly designed for this purpose but are infrequently used outside investigational studies. The extent to which the revised McGeer and Loeb criteria overlap and can be used interchangeably for tracking antibiotic appropriateness in nursing homes remains insufficiently studied.

We conducted a cross-sectional chart review study in 5 Wisconsin nursing homes and applied the revised McGeer and Loeb criteria to all nursing home–initiated antibiotic treatment courses. Kappa (κ) statistics were employed to assess level of agreement overall and by treatment indications.

Overall, 734 eligible antibiotic courses were initiated in participating nursing homes during the study period. Of 734 antibiotic courses, 372 (51%) satisfied the Loeb criteria, while only 211 (29%) of 734 satisfied the revised McGeer criteria. Only 169 (23%) of 734 antibiotic courses satisfied both criteria, and the overall level of agreement between them was fair (κ = 0.35). When stratified by infection type, levels of agreement between the revised McGeer and Loeb criteria were moderate for urinary tract infections (κ = 0.45), fair for skin and soft-tissue infections (0.36), and slight for respiratory tract infections (0.17).

Agreement between the revised McGeer and Loeb criteria is limited, and nursing homes should employ the revised McGeer and Loeb criteria for their intended purposes. Studies to establish the best method for ongoing monitoring of antibiotic appropriateness in nursing homes are needed.

To study the airflow, transmission, and clearance of aerosols in the clinical spaces of a hospital ward that had been used to care for patients with coronavirus disease 2019 (COVID-19) and to examine the impact of portable air cleaners on aerosol clearance.

Observational study.

A single ward of a tertiary-care public hospital in Melbourne, Australia.

Glycerin-based aerosol was used as a surrogate for respiratory aerosols. The transmission of aerosols from a single patient room into corridors and a nurses’ station in the ward was measured. The rate of clearance of aerosols was measured over time from the patient room, nurses’ station and ward corridors with and without air cleaners [ie, portable high-efficiency particulate air (HEPA) filters].

Aerosols rapidly travelled from the patient room into other parts of the ward. Air cleaners were effective in increasing the clearance of aerosols from the air in clinical spaces and reducing their spread to other areas. With 2 small domestic air cleaners in a single patient room of a hospital ward, 99% of aerosols could be cleared within 5.5 minutes.

Air cleaners may be useful in clinical spaces to help reduce the risk of acquisition of respiratory viruses that are transmitted via aerosols. They are easy to deploy and are likely to be cost-effective in a variety of healthcare settings.

To determine the impact of clinical decision support on guideline-concordant Clostridioides difficile infection (CDI) treatment.

Quasi-experimental study in >50 ambulatory clinics.

Primary, specialty, and urgent-care clinics.

Adult patients were eligible for inclusion if they were diagnosed with and treated for a first episode of symptomatic CDI at an ambulatory clinic between November 1, 2019, and November 30, 2020.

An outpatient best practice advisory (BPA) was implemented to notify prescribers that “vancomycin or fidaxomicin are preferred over metronidazole for C.difficile infection” when metronidazole was prescribed to a patient with CDI.

In total, 189 patients were included in the study: 92 before the BPA and 97 after the BPA. Their median age was 59 years; 31% were male; 75% were white; 30% had CDI-related comorbidities; 35% had healthcare exposure; 65% had antibiotic exposure; 44% had gastric acid suppression therapy within 90 days of CDI diagnosis. The BPA was accepted 23 of 26 times and was used to optimize the therapy of 16 patients in 6 months. Guideline-concordant therapy increased after implementation of the BPA (72% vs 91%; P = .001). Vancomycin prescribing increased and metronidazole prescribing decreased after the BPA. There was no difference in clinical response or unplanned encounter within 14 days after treatment initiation. Fewer patients after the BPA had CDI recurrence within 14–56 days of the initial episode (27% vs 7%; P < .001).

Clinical decision support increased prescribing of guideline-concordant CDI therapy in the outpatient setting. A targeted BPA is an effective stewardship intervention and may be especially useful in settings with limited antimicrobial stewardship resources.

The “HygArzt” project investigated the effectiveness of hygiene measures introduced by an infection prevention link physician (PLP).

To investigate whether the introduction of a standardized aseptic dressing change concept (ADCC) by a PLP can increase hand hygiene adherence and adherence to specific process steps during an aseptic dressing change (ADC) in a trauma surgery and orthopedic department.

We defined 4 required hand disinfection indications: (1) before the preparation of ADC equipment, (2) immediately before the ADC, (3) before the clean phase, and (4) after the ADC. A process analysis of the preintervention phase (331 ADCs) was used to develop a standardized ADCC. The ADCC was introduced and iteratively adopted during the intervention phase. The effect was evaluated during the postintervention phase (374 ADCs).

Hand hygiene adherence was significantly increased by the introduction of the ADCC for all indications: (1) before the preparation of the ADC equipment (from 34% before to 85% after, P <.001), (2) immediately before an ADC (from 32% before to 85% after; P < .001), (3) before the clean phase (from 42% before to 96% after; P < .001), and (4) after an ADC (from 74% before to 99% after; P < .001). Overall hand hygiene adherence was analyzed before the indications for an ADC (from 9.6% before to 74% after; P < .001). The same strategy was applied to the following process parameters: use of a clean work surface, clean withdrawal of equipment from the dressing trolley, and appropriate waste disposal.

A PLP sufficiently implemented a standardized concept for aseptic dressing change during an iterative improvement process, which resulted in a significant improvement in hand hygiene and adherence to other specific ADCC process steps.

We examined the impact of microbiological results from respiratory samples on choice of antibiotic therapy in patients treated for hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP).

Four-year retrospective study.

Veterans’ Health Administration (VHA).

VHA patients hospitalized with HAP or VAP and with respiratory cultures between October 1, 2014, and September 30, 2018.

We compared patients with positive and negative respiratory culture results, assessing changes in antibiotic class and Antibiotic Spectrum Index (ASI) from the day of sample collection (day 0) through day 7.

Between October 1, 2014, and September 30, 2018, we identified 5,086 patients with HAP/VAP: 2,952 with positive culture results and 2,134 with negative culture results. All-cause 30-day mortality was 21% for both groups. The mean time from respiratory sample receipt in the laboratory to final respiratory culture result was longer for those with positive (2.9 ± 1.3 days) compared to negative results (2.5 ± 1.3 days; P < .001). The most common pathogens were Staphylococcus aureus and Pseudomonas aeruginosa. Vancomycin and β-lactam/β-lactamase inhibitors were the most commonly prescribed agents. The decrease in the median ASI from 13 to 8 between days 0 and 6 was similar among patients with positive and negative respiratory cultures. Patients with negative cultures were more likely to be off antibiotics from day 3 onward.

The results of respiratory cultures had only a small influence on antibiotics used during the treatment of HAP/VAP. The decrease in ASI for both groups suggests the integration of antibiotic stewardship principles, including de-escalation, into the care of patients with HAP/VAP.

To assess the rate and factors associated with healthcare personnel (HCP) testing positive for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) after an occupational exposure.

Retrospective cohort study.

Academic medical center with sites in Minnesota, Wisconsin, Arizona, and Florida.

HCP with a high or medium risk occupational exposure to a patient or other HCP with SARS-CoV-2.

We reviewed the records of HCP with significant occupational exposures from March 20, 2020, through December 31, 2020. We then performed regression analysis to assess the impact of demographic and occupational variables to assess their impact on the likelihood of testing positive for SARS-CoV-2.

In total, 2,253 confirmed occupational exposures occurred during the study period. Employees were the source for 57.1% of exposures. Overall, 101 HCP (4.5%) tested positive in the postexposure period. Of these, 80 had employee sources of exposure and 21 had patient sources of exposure. The postexposure infection rate was 6.2% when employees were the source, compared to 2.2% with patient sources. In a multivariate analysis, occupational exposure from an employee source had a higher risk of testing positive compared to a patient source (odds ratio [OR], 3.22; 95% confidence interval [CI], 1.72–6.04). Sex, age, high-risk exposure, and HCP role were not associated with an increased risk of testing positive.

The risk of acquiring coronavirus disease 2019 (COVID-19) following a significant occupational exposure has remained relatively low, even in the prevaccination era. Exposure to an infectious coworker carries a higher risk than exposure to a patient. Continued vigilance and precautions remain necessary in healthcare settings.