To provide comprehensive population-level estimates of the burden of healthcare-associated influenza.

Retrospective cross-sectional study.

US Influenza Hospitalization Surveillance Network (FluSurv-NET) during 2012–2013 through 2018–2019 influenza seasons.

Laboratory-confirmed influenza-related hospitalizations in an 8-county catchment area in Tennessee.

The incidence of healthcare-associated influenza was determined using the traditional definition (ie, positive influenza test after hospital day 3) in addition to often underrecognized cases associated with recent post-acute care facility admission or a recent acute care hospitalization for a noninfluenza illness in the preceding 7 days.

Among the 5,904 laboratory-confirmed influenza-related hospitalizations, 147 (2.5%) had traditionally defined healthcare-associated influenza. When we included patients with a positive influenza test obtained in the first 3 days of hospitalization and who were either transferred to the hospital directly from a post-acute care facility or who were recently discharged from an acute care facility for a noninfluenza illness in the preceding 7 days, we identified an additional 1,031 cases (17.5% of all influenza-related hospitalizations).

Including influenza cases associated with preadmission healthcare exposures with traditionally defined cases resulted in an 8-fold higher incidence of healthcare-associated influenza. These results emphasize the importance of capturing other healthcare exposures that may serve as the initial site of viral transmission to provide more comprehensive estimates of the burden of healthcare-associated influenza and to inform improved infection prevention strategies.

Admission laboratory screening for asymptomatic coronavirus disease 2019 (COVID-19) has been utilized to mitigate healthcare-associated severe acute respiratory coronavirus virus 2 (SARS-CoV-2) transmission. An understanding of the impact of such testing across a variety of patient populations is needed.

SARS-CoV-2 nucleic acid amplification admission testing results for all asymptomatic patients across 4 distinct inpatient facilities between April 20, 2020, and June 14, 2021, were analyzed. Positivity rates and the number needed to test (NNT) to identify 1 asymptomatic infected patient were calculated. Admission results were compared to COVID-19 community incidence rates for the system’s surrounding metropolitan service area. Using a national survey of hospital epidemiologists, a clinically meaningful NNT of 1:100 was identified.

In total, 51,187 tests were collected (positivity rate, 1.8%). During periods of high transmission, the NNT met the clinically relevant threshold in all populations. The NNT approached or met the threshold for most locations during periods of lower transmission. For all transmission levels, the NNT for fully vaccinated patients did not meet the threshold.

Implementing an asymptomatic patient admission testing program can provide clinically relevant data based on the NNT, even during periods of lower transmission and among different patient populations. Limiting admission testing to non–fully vaccinated patients during periods of lower transmission may be a strategy to address resource concerns around this practice. Although the impact of such testing on healthcare-associated COVID-19 among patients and healthcare workers could not be clearly determined, these data provide important information as facilities weigh the costs and benefits of such testing.

Although a growing number of healthcare facilities are implementing healthcare personnel (HCP) coronavirus disease 2019 (COVID-19) vaccination requirements, vaccine exemption request management as a part of such programs is not well described.

Cross-sectional survey.

Infectious disease (ID) physician members of the Emerging Infections Network with infection prevention or hospital epidemiology responsibilities.

Eligible persons were sent a web-based survey focused on hospital plans and practices around exemption allowances from HCP COVID-19 vaccine requirements.

Of the 695 ID physicians surveyed, 263 (38%) responded. Overall, 160 respondent institutions (92%) allowed medical exemptions, whereas 132 (76%) allowed religious exemptions. In contrast, only 14% (n = 24) allowed deeply held personal belief exemptions. The types of medical exemptions allowed varied considerably across facilities, with allergic reactions to the vaccine or its components accepted by 145 facilities (84%). For selected scenarios commonly used as the basis for religious and deeply held personal belief exemption requests, 144 institutions (83%) would not approve exemptions focused on concerns regarding right of consent or violations of freedom of personal choice, and 140 institutions (81%) would not approve exemptions focused on introducing foreign substances into one’s body or the sanctity of the body. Most respondents noted plans for additional infection prevention interventions for HCP who received an exemption for COVID-19 vaccination.

Although many respondent institutions allowed exemptions from HCP COVID-19 vaccination requirements, the types of exemptions allowed and how the exemption programs were structured varied widely.

Evaluation of a mandatory immunization program to increase and sustain high immunization coverage for healthcare personnel (HCP).

Descriptive study with before-and-after analysis.

Tertiary-care academic medical center.

Medical center HCP.

A comprehensive mandatory immunization initiative was implemented in 2 phases, starting in July 2014. Key facets of the initiative included a formalized exemption review process, incorporation into institutional quality goals, data feedback, and accountability to support compliance.

Both immunization and overall compliance rates with targeted immunizations increased significantly in the years after the implementation period. The influenza immunization rate increased from 80% the year prior to the initiative to >97% for the 3 subsequent influenza seasons (P < .0001). Mumps, measles and varicella vaccination compliance increased from 94% in January 2014 to >99% by January 2017, rubella vaccination compliance increased from 93% to 99.5%, and hepatitis B vaccination compliance from 95% to 99% (P < .0001 for all comparisons). An associated positive effect on TB testing compliance, which was not included in the mandatory program, was also noted; it increased from 76% to 92% over the same period (P < .0001).

Thoughtful, step-wise implementation of a mandatory immunization program linked to professional accountability can be successful in increasing immunization rates as well as overall compliance with policy requirements to cover all recommended HCP immunizations.

Vanderbilt University Medical Center (VUMC) requires that all faculty and staff receive the seasonal influenza vaccine annually or receive an approved vaccine exemption, either for a medical or deeply held religious or personal belief. We sought to understand the underlying principles behind these exemption requests and their interaction with a multidisciplinary exemption review process.

All of the personal and religious exemption requests at VUMC for 3 consecutive influenza seasons from 2015 to 2018 were analyzed, categorizing these requests by 1 of 12 standardized employee categories and 1 of 18 unique reasons for vaccine exemption.

Tertiary-care academic medical center.

Healthcare personnel (HCP).

Among the 3 influenza seasons, 1.1%–2.1% of all VUMC HCP requested religious or personal exemption from vaccination. The frequency of religious and personal exemption approval increased annually from 296 of 452 (65.5%) to 196 of 248 (80.2%) to 283 of 323 (87.6%) over the 3 seasons, representing a statistically significant increase each year. Of the 5 most common reasons against vaccination, 4 were explicitly religious in nature; the most common reason was that the “body is a temple or sacred.” Nonclinical staff submitted the most religious and personal exemption requests of any job category, submitting approximately one-third of all requests every year.

These results demonstrate how detailed the personal or religious convictions behind vaccine avoidance can be among HCP and how vaccine avoidance stems from much more than simple misinformation regarding vaccination. The intersection between misinformation and personal or religious beliefs provides a unique opportunity to address HCP opinions toward vaccination in an exemption and appeals process like the one described here.

To characterize associations between exposures within and outside the medical workplace with healthcare personnel (HCP) SARS-CoV-2 infection, including the effect of various forms of respiratory protection.

Case–control study.

We collected data from international participants via an online survey.

In total, 1,130 HCP (244 cases with laboratory-confirmed COVID-19, and 886 controls healthy throughout the pandemic) from 67 countries not meeting prespecified exclusion (ie, healthy but not working, missing workplace exposure data, COVID symptoms without lab confirmation) were included in this study.

Respondents were queried regarding workplace exposures, respiratory protection, and extra-occupational activities. Odds ratios for HCP infection were calculated using multivariable logistic regression and sensitivity analyses controlling for confounders and known biases.

HCP infection was associated with non–aerosol-generating contact with COVID-19 patients (adjusted OR, 1.4; 95% CI, 1.04–1.9; P = .03) and extra-occupational exposures including gatherings of ≥10 people, patronizing restaurants or bars, and public transportation (adjusted OR range, 3.1–16.2). Respirator use during aerosol-generating procedures (AGPs) was associated with lower odds of HCP infection (adjusted OR, 0.4; 95% CI, 0.2–0.8, P = .005), as was exposure to intensive care and dedicated COVID units, negative pressure rooms, and personal protective equipment (PPE) observers (adjusted OR range, 0.4–0.7).

COVID-19 transmission to HCP was associated with medical exposures currently considered lower-risk and multiple extra-occupational exposures, and exposures associated with proper use of appropriate PPE were protective. Closer scrutiny of infection control measures surrounding healthcare activities and medical settings considered lower risk, and continued awareness of the risks of public congregation, may reduce the incidence of HCP infection.

To identify risk factors of patients placed in airborne infection isolation (AII) for possible pulmonary tuberculosis (TB) to better predict TB diagnosis and allow more judicious use of AII.

Case-control, retrospective study at a single tertiary-care academic medical center. The study included all adult patients admitted from October 1, 2014, through October 31, 2017, who were placed in AII for possible pulmonary TB. Cases were defined as those ultimately diagnosed with pulmonary TB. Controls were defined as those not diagnosed with pulmonary TB. Those with TB diagnosed prior to admission were excluded. In total, 662 admissions (558 patients) were included.

Overall, 15 cases of pulmonary TB were identified (2.7%); of these, 2 were people living with human immunodeficiency virus (HIV; PLWH). Statistical analysis was limited by low case number. Those diagnosed with pulmonary TB were more likely to have been born outside the United States (53% vs 13%; P < .001) and to have had prior positive TB testing, regardless of prior treatment (50% vs 19%; P = .015). A multivariate analysis using non–US birth and prior positive TB testing predicted an 18.2% probability of pulmonary TB diagnosis when present, compared with 1.0% if both factors were not present.

The low number of pulmonary TB cases indicated AII overuse, especially in PLWH, and more judicious use of AII is warranted. High-risk groups, including those born outside the United States and those with prior positive TB testing, should be considered for AII in the appropriate clinical setting.

Ventilator bundles encompass practices that reduce the risk of ventilator complications, including ventilator-associated pneumonia. The impact of ventilator bundles on the risk of developing ventilator-associated events (VAEs) is unknown. We sought to determine whether decreased compliance to the ventilator bundle increases the risk for VAE development.

Nested case-control study.

This study was conducted at 6 adult intensive care units at an academic tertiary-care center in Tennessee.

In total, 273 patients with VAEs were randomly matched in a 1:4 ratio to controls by mechanical ventilation duration and ICU type.

Controls were selected from the primary study population at risk for a VAE after being mechanically ventilated for the same number of days as a specified case. Using conditional logistic regression analysis, overall cumulative compliance, and compliance with individual components of the bundle in the 3 and 7 days prior to VAE development (or the control match day) were examined.

Overall bundle compliance at 3 days (odds ratio [OR], 1.15; P=.34) and 7 days prior to VAE diagnosis (OR, 0.96; P=.83) were not associated with VAE development. This finding did not change when limiting the outcome to infection-related ventilator-associated complications (IVACs) and after adjusting for age and gender. In the examination of compliance with specific bundle components increased compliance with chlorhexidine oral care was associated with increased risk of VAE development in all analyses.

Ventilator bundle compliance was not associated with a reduced risk for VAEs. Higher compliance with chlorhexidine oral care was associated with a greater risk for VAE development.

Infect Control Hosp Epidemiol 2018;39:637–643

Outpatient central venous catheters (CVCs) are being used more frequently; however, data describing mechanical complications and central-line–associated bloodstream infections (CLABSI) in the outpatient setting are limited. We performed a retrospective observational cohort study to understand the burden of these complications to elucidate their impact on the healthcare system.

Data were retrospectively collected on patients discharged from Vanderbilt University Medical Center with a CVC in place and admitted into the care of Vanderbilt Home Care Services. Risk factors for medically attended catheter-associated complications (CACs) and outpatient CLABSIs were analyzed.

A CAC developed in 143 patients (21.9%), for a total of 165 discrete CAC events. Among these, 76 (46%) required at least 1 visit to the emergency department or an inpatient admission, while the remaining 89 (54%) required an outpatient clinic visit. The risk for developing a CAC was significantly increased in female patients, patients with a CVC with >1 lumen, and patients receiving total parenteral nutrition. The absolute number of CLABSIs identified in the study population was small at 16, or 2.4% of the total cohort.

Medically attended catheter complications were common among outpatients discharged with a CVC, and reduction of these events should be the focus of outpatient quality improvement programs.

Infect Control Hosp Epidemiol 2018;39:439–444

Infants and young children are frequently colonized with C. difficile but rarely have symptomatic disease. However, C. difficile testing remains prevalent in this age group.

To design a computerized provider order entry (CPOE) alert to decrease testing for C. difficile in young children and infants.

An interventional age-targeted before-after trial with comparison group

Monroe Carell Jr. Children’s Hospital at Vanderbilt University, Nashville, Tennessee.

All children seen in the inpatient or emergency room settings from July 2012 through July 2013 (pre-CPOE alert) and September 2013 through September 2014 (post-CPOE alert)

In August of 2013, we implemented a CPOE alert advising against testing in infants and young children based on the American Academy of Pediatrics recommendations with an optional override. We further offered healthcare providers educational seminars regarding recommended C. difficile testing.

The average monthly testing rate significantly decreased after the CPOE alert for children 0–11 months old (11.5 pre-alert vs 0 post-alert per 10,000 patient days; P<.001) and 12–35 months old (61.6 pre-alert vs 30.1 post-alert per 10,000 patients days; P<.001), but not for those children ≥36 months old (50.9 pre-alert vs 46.4 post-alert per 10,000 patient days; P=.3) who were not targeted with a CPOE alert. There were no complications in those children who testing positive for C. difficile.

The average monthly testing rate for C. difficile for children <35 months old decreased without complication after the use of a CPOE alert in those who tested positive for C. difficile.

Infect Control Hosp Epidemiol 2017;38:542–546

We report an outbreak of respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) infections in a dementia care ward containing 2 separately locked units (A and B) to heighten awareness of these pathogens in the older adult population and highlight some of the infection prevention challenges faced during a noninfluenza respiratory viral outbreak in a congregate setting.

Cases were defined by the presence of new signs or symptoms that included (1) a single oral temperature ≥ 37.8°C (100.0°F) and (2) the presence of at least 2 of the following symptoms: cough, dyspnea, rhinorrhea, hoarseness, congestion, fatigue, and malaise. Attempted infection-control measures included cohorting patients and staff, empiric isolation precautions, and cessation of group activities. Available nasopharyngeal swab specimens were sent to the Tennessee Department of Health for identification by rT-PCR testing.

We identified 30 of the 41 (73%) residents as cases over this 16-day outbreak. Due to high numbers of sick personnel, we were unable to cohort staff to 1 unit. Unit B developed its first case 8 days after infection control measures were implemented. Of the 14 cases with available specimens, 6 patients tested positive for RSV-B, 7 for HMPV and 1 patient test positive for influenza A. Overall, 15 cases (50%) required transfer to acute care facilities; 10 of these patients (34%) had chest x-ray confirmed pulmonary infiltrates; and 5 residents (17%) died.

This case report highlights the importance of RSV and HMPV in causing substantial disease in the older adult population and highlights the challenges in preventing transmission of these viruses.

Infect Control Hosp Epidemiol 2017;38:399–404

The effectiveness of practice bundles on reducing ventilator-associated pneumonia (VAP) has been questioned.

To implement a comprehensive program that included a real-time bundle compliance dashboard to improve compliance and reduce ventilator-associated complications.

Before-and-after quasi-experimental study with interrupted time-series analysis.

Academic medical center.

In 2007 a comprehensive institutional ventilator bundle program was developed. To assess bundle compliance and stimulate instant course correction of noncompliant parameters, a real-time computerized dashboard was developed. Program impact in 6 adult intensive care units (ICUs) was assessed. Bundle compliance was noted as an overall cumulative bundle adherence assessment, reflecting the percentage of time all elements were concurrently in compliance for all patients.

The VAP rate in all ICUs combined decreased from 19.5 to 9.2 VAPs per 1,000 ventilator-days following program implementation (P<.001). Bundle compliance significantly increased (Z100 score of 23% in August 2007 to 83% in June 2011 [P<.001]). The implementation resulted in a significant monthly decrease in the overall ICU VAP rate of 3.28/1,000 ventilator-days (95% CI, 2.64–3.92/1,000 ventilator-days). Following the intervention, the VAP rate decreased significantly at a rate of 0.20/1,000 ventilator-days per month (95% CI, 0.14–0.30/1,000 ventilator-days per month). Among all adult ICUs combined, improved bundle compliance was moderately correlated with monthly VAP rate reductions (Pearson correlation coefficient, −0.32).

A prevention program using a real-time bundle adherence dashboard was associated with significant sustained decreases in VAP rates and an increase in bundle compliance among adult ICU patients.

Infect. Control Hosp. Epidemiol. 2015;36(11):1261–1267