Determinants of de novo B cell responses to drifted epitopes in post-vaccination SARS-CoV-2 infections

Vaccine-induced immunity may impact subsequent de novo responses to drifted epitopes in SARS-CoV-2 variants, but this has been difficult to quantify due to the challenges in recruiting unvaccinated control groups whose first exposure to SARS-CoV-2 is a primary infection. Through local, statewide, and national SARS-CoV-2 testing programs, we were able to recruit cohorts of individuals who had recovered from either primary or post-vaccination infections by either the Delta or Omicron BA.1 variants. Regardless of variant, we observed greater Spike-specific and neutralizing antibody responses in post-vaccination infections than in those who were infected without prior vaccination. Through analysis of variant-specific memory B cells as markers of de novo responses, we observed that Delta and Omicron BA.1 infections led to a marked shift in immunodominance in which some drifted epitopes elicited minimal responses, even in primary infections. Prior immunity through vaccination had a small negative impact on these de novo responses, but this did not correlate with cross-reactive memory B cells, arguing against competitive inhibition of naïve B cells. We conclude that dampened de novo B cell responses against drifted epitopes are mostly a function of altered immunodominance hierarchies that are apparent even in primary infections, with a more modest contribution from pre-existing immunity, perhaps due to accelerated antigen clearance.

Association of mRNA Vaccination With Clinical and Virologic Features of COVID-19 Among US Essential and Frontline Workers

Importance

Data on the epidemiology of mild to moderately severe COVID-19 are needed to inform public health guidance.

Objective

To evaluate associations between 2 or 3 doses of mRNA COVID-19 vaccine and attenuation of symptoms and viral RNA load across SARS-CoV-2 viral lineages.

Design, Setting, and Participants

A prospective cohort study of essential and frontline workers in Arizona, Florida, Minnesota, Oregon, Texas, and Utah with COVID-19 infection confirmed by reverse transcriptase-polymerase chain reaction testing and lineage classified by whole genome sequencing of specimens self-collected weekly and at COVID-19 illness symptom onset. This analysis was conducted among 1199 participants with SARS-CoV-2 from December 14, 2020, to April 19, 2022, with follow-up until May 9, 2022, reported.

Exposures

SARS-CoV-2 lineage (origin strain, Delta variant, Omicron variant) and COVID-19 vaccination status.

Main Outcomes and Measures

Clinical outcomes included presence of symptoms, specific symptoms (including fever or chills), illness duration, and medical care seeking. Virologic outcomes included viral load by quantitative reverse transcriptase-polymerase chain reaction testing along with viral viability.

Results

Among 1199 participants with COVID-19 infection (714 [59.5%] women; median age, 41 years), 14.0% were infected with the origin strain, 24.0% with the Delta variant, and 62.0% with the Omicron variant. Participants vaccinated with the second vaccine dose 14 to 149 days before Delta infection were significantly less likely to be symptomatic compared with unvaccinated participants (21/27 [77.8%] vs 74/77 [96.1%]; OR, 0.13 [95% CI, 0-0.6]) and, when symptomatic, those vaccinated with the third dose 7 to 149 days before infection were significantly less likely to report fever or chills (5/13 [38.5%] vs 62/73 [84.9%]; OR, 0.07 [95% CI, 0.0-0.3]) and reported significantly fewer days of symptoms (10.2 vs 16.4; difference, -6.1 [95% CI, -11.8 to -0.4] days). Among those with Omicron infection, the risk of symptomatic infection did not differ significantly for the 2-dose vaccination status vs unvaccinated status and was significantly higher for the 3-dose recipients vs those who were unvaccinated (327/370 [88.4%] vs 85/107 [79.4%]; OR, 2.0 [95% CI, 1.1-3.5]). Among symptomatic Omicron infections, those vaccinated with the third dose 7 to 149 days before infection compared with those who were unvaccinated were significantly less likely to report fever or chills (160/311 [51.5%] vs 64/81 [79.0%]; OR, 0.25 [95% CI, 0.1-0.5]) or seek medical care (45/308 [14.6%] vs 20/81 [24.7%]; OR, 0.45 [95% CI, 0.2-0.9]). Participants with Delta and Omicron infections who received the second dose 14 to 149 days before infection had a significantly lower mean viral load compared with unvaccinated participants (3 vs 4.1 log10 copies/μL; difference, -1.0 [95% CI, -1.7 to -0.2] for Delta and 2.8 vs 3.5 log10 copies/μL, difference, -1.0 [95% CI, -1.7 to -0.3] for Omicron).

Conclusions and Relevance

In a cohort of US essential and frontline workers with SARS-CoV-2 infections, recent vaccination with 2 or 3 mRNA vaccine doses less than 150 days before infection with Delta or Omicron variants, compared with being unvaccinated, was associated with attenuated symptoms, duration of illness, medical care seeking, or viral load for some comparisons, although the precision and statistical significance of specific estimates varied.

Pediatric Research Observing Trends and Exposures in COVID-19 Timelines (PROTECT): Protocol for a Multisite Longitudinal Cohort Study

BACKGROUND

Assessing the real-world effectiveness of COVID-19 vaccines and understanding the incidence and severity of SARS-CoV-2 illness in children are essential to inform policy and guide health care professionals in advising parents and caregivers of children who test positive for SARS-CoV-2.

OBJECTIVE

This report describes the objectives and methods for conducting the Pediatric Research Observing Trends and Exposures in COVID-19 Timelines (PROTECT) study. PROTECT is a longitudinal prospective pediatric cohort study designed to estimate SARS-CoV-2 incidence and COVID-19 vaccine effectiveness (VE) against infection among children aged 6 months to 17 years, as well as differences in SARS-CoV-2 infection and vaccine response between children and adolescents.

METHODS

The PROTECT multisite network was initiated in July 2021, which aims to enroll approximately 2305 children across four US locations and collect data over a 2-year surveillance period. The enrollment target was based on prospective power calculations and accounts for expected attrition and nonresponse. Study sites recruit parents and legal guardians of age-eligible children participating in the existing Arizona Healthcare, Emergency Response, and Other Essential Workers Surveillance (HEROES)-Research on the Epidemiology of SARS-CoV-2 in Essential Response Personnel (RECOVER) network as well as from surrounding communities. Child demographics, medical history, COVID-19 exposure, vaccination history, and parents/legal guardians' knowledge and attitudes about COVID-19 are collected at baseline and throughout the study. Mid-turbinate nasal specimens are self-collected or collected by parents/legal guardians weekly, regardless of symptoms, for SARS-CoV-2 and influenza testing via reverse transcription-polymerase chain reaction (RT-PCR) assay, and the presence of COVID-like illness (CLI) is reported. Children who test positive for SARS-CoV-2 or influenza, or report CLI are monitored weekly by online surveys to report exposure and medical utilization until no longer ill. Children, with permission of their parents/legal guardians, may elect to contribute blood at enrollment, following SARS-CoV-2 infection, following COVID-19 vaccination, and at the end of the study period. PROTECT uses electronic medical record (EMR) linkages where available, and verifies COVID-19 and influenza vaccinations through EMR or state vaccine registries.

RESULTS

Data collection began in July 2021 and is expected to continue through the spring of 2023. As of April 13, 2022, 2371 children are enrolled in PROTECT. Enrollment is ongoing at all study sites.

CONCLUSIONS

As COVID-19 vaccine products are authorized for use in pediatric populations, PROTECT study data will provide real-world estimates of VE in preventing infection. In addition, this prospective cohort provides a unique opportunity to further understand SARS-CoV-2 incidence, clinical course, and key knowledge gaps that may inform public health.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/37929.

Effectiveness of COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Frontline Workers Before and During B.1.617.2 (Delta) Variant Predominance - Eight U.S. Locations, December 2020-August 2021

During December 14, 2020-April 10, 2021, data from the HEROES-RECOVER Cohorts,* a network of prospective cohorts among frontline workers, showed that the Pfizer-BioNTech and Moderna mRNA COVID-19 vaccines were approximately 90% effective in preventing symptomatic and asymptomatic infection with SARS-CoV-2, the virus that causes COVID-19, in real-world conditions (1,2). This report updates vaccine effectiveness (VE) estimates including all COVID-19 vaccines available through August 14, 2021, and examines whether VE differs for adults with increasing time since completion of all recommended vaccine doses. VE before and during SARS-CoV-2 B.1.617.2 (Delta) variant predominance, which coincided with an increase in reported COVID-19 vaccine breakthrough infections, were compared (3,4).

Prevention and Attenuation of Covid-19 with the BNT162b2 and mRNA-1273 Vaccines

BACKGROUND

Information is limited regarding the effectiveness of the two-dose messenger RNA (mRNA) vaccines BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) in preventing infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and in attenuating coronavirus disease 2019 (Covid-19) when administered in real-world conditions.

METHODS

We conducted a prospective cohort study involving 3975 health care personnel, first responders, and other essential and frontline workers. From December 14, 2020, to April 10, 2021, the participants completed weekly SARS-CoV-2 testing by providing mid-turbinate nasal swabs for qualitative and quantitative reverse-transcriptase-polymerase-chain-reaction (RT-PCR) analysis. The formula for calculating vaccine effectiveness was 100% × (1 - hazard ratio for SARS-CoV-2 infection in vaccinated vs. unvaccinated participants), with adjustments for the propensity to be vaccinated, study site, occupation, and local viral circulation.

RESULTS

SARS-CoV-2 was detected in 204 participants (5%), of whom 5 were fully vaccinated (≥14 days after dose 2), 11 partially vaccinated (≥14 days after dose 1 and <14 days after dose 2), and 156 unvaccinated; the 32 participants with indeterminate vaccination status (<14 days after dose 1) were excluded. Adjusted vaccine effectiveness was 91% (95% confidence interval [CI], 76 to 97) with full vaccination and 81% (95% CI, 64 to 90) with partial vaccination. Among participants with SARS-CoV-2 infection, the mean viral RNA load was 40% lower (95% CI, 16 to 57) in partially or fully vaccinated participants than in unvaccinated participants. In addition, the risk of febrile symptoms was 58% lower (relative risk, 0.42; 95% CI, 0.18 to 0.98) and the duration of illness was shorter, with 2.3 fewer days spent sick in bed (95% CI, 0.8 to 3.7).

CONCLUSIONS

Authorized mRNA vaccines were highly effective among working-age adults in preventing SARS-CoV-2 infection when administered in real-world conditions, and the vaccines attenuated the viral RNA load, risk of febrile symptoms, and duration of illness among those who had breakthrough infection despite vaccination. (Funded by the National Center for Immunization and Respiratory Diseases and the Centers for Disease Control and Prevention.).

Interim Estimates of Vaccine Effectiveness of BNT162b2 and mRNA-1273 COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Health Care Personnel, First Responders, and Other Essential and Frontline Workers - Eight U.S. Locations, December 2020-March 2021

Messenger RNA (mRNA) BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) COVID-19 vaccines have been shown to be effective in preventing symptomatic COVID-19 in randomized placebo-controlled Phase III trials (1,2); however, the benefits of these vaccines for preventing asymptomatic and symptomatic SARS-CoV-2 (the virus that causes COVID-19) infection, particularly when administered in real-world conditions, is less well understood. Using prospective cohorts of health care personnel, first responders, and other essential and frontline workers* in eight U.S. locations during December 14, 2020-March 13, 2021, CDC routinely tested for SARS-CoV-2 infections every week regardless of symptom status and at the onset of symptoms consistent with COVID-19-associated illness. Among 3,950 participants with no previous laboratory documentation of SARS-CoV-2 infection, 2,479 (62.8%) received both recommended mRNA doses and 477 (12.1%) received only one dose of mRNA vaccine.^† Among unvaccinated participants, 1.38 SARS-CoV-2 infections were confirmed by reverse transcription-polymerase chain reaction (RT-PCR) per 1,000 person-days.^§ In contrast, among fully immunized (≥14 days after second dose) persons, 0.04 infections per 1,000 person-days were reported, and among partially immunized (≥14 days after first dose and before second dose) persons, 0.19 infections per 1,000 person-days were reported. Estimated mRNA vaccine effectiveness for prevention of infection, adjusted for study site, was 90% for full immunization and 80% for partial immunization. These findings indicate that authorized mRNA COVID-19 vaccines are effective for preventing SARS-CoV-2 infection, regardless of symptom status, among working-age adults in real-world conditions. COVID-19 vaccination is recommended for all eligible persons.

Interim Estimates of Vaccine Effectiveness of BNT162b2 and mRNA-1273 COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Health Care Personnel, First Responders, and Other Essential and Frontline Workers - Eight U.S. Locations, December 2020-March 2021

Messenger RNA (mRNA) BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) COVID-19 vaccines have been shown to be effective in preventing symptomatic COVID-19 in randomized placebo-controlled Phase III trials (1,2); however, the benefits of these vaccines for preventing asymptomatic and symptomatic SARS-CoV-2 (the virus that causes COVID-19) infection, particularly when administered in real-world conditions, is less well understood. Using prospective cohorts of health care personnel, first responders, and other essential and frontline workers* in eight U.S. locations during December 14, 2020-March 13, 2021, CDC routinely tested for SARS-CoV-2 infections every week regardless of symptom status and at the onset of symptoms consistent with COVID-19-associated illness. Among 3,950 participants with no previous laboratory documentation of SARS-CoV-2 infection, 2,479 (62.8%) received both recommended mRNA doses and 477 (12.1%) received only one dose of mRNA vaccine.† Among unvaccinated participants, 1.38 SARS-CoV-2 infections were confirmed by reverse transcription-polymerase chain reaction (RT-PCR) per 1,000 person-days.§ In contrast, among fully immunized (≥14 days after second dose) persons, 0.04 infections per 1,000 person-days were reported, and among partially immunized (≥14 days after first dose and before second dose) persons, 0.19 infections per 1,000 person-days were reported. Estimated mRNA vaccine effectiveness for prevention of infection, adjusted for study site, was 90% for full immunization and 80% for partial immunization. These findings indicate that authorized mRNA COVID-19 vaccines are effective for preventing SARS-CoV-2 infection, regardless of symptom status, among working-age adults in real-world conditions. COVID-19 vaccination is recommended for all eligible persons.

Methodology minute: An overview of the case-case study design and its applications in infection prevention

The case-case study design is a potentially useful tool for infection preventionists during outbreak or cluster investigations. This column clarifies terminology related to case-case, case-control, and case-case-control study designs. Examples of practical applications of the case-case study design include determining risk factors for health care-onset versus community-onset infections, or antibiotic-resistant versus antibiotic-susceptible infections.

1216. A Novel Antimicrobial Surface Coating Demonstrates Persistent Reduction of both Microbial Burden and Healthcare-Associated Infections at Two High-acuity Hospitals

Background

Healthcare-Associated Infections (HAIs) pose substantial risks to patients and hospitals. Surface disinfection practices in hospitals have limited efficacy because surfaces are frequently and easily re-contaminated. A need for innovative technologies to address these challenges exists. One such innovation is a novel antimicrobial surface coating with potential to persistently reduce environmental bacterial load. Here, we use a multicenter, nonrandomized, controlled, pre-post study design to assess the impact of an antimicrobial surface coating on environmental bioburden and HAIs at two high acuity hospitals.

Methods

An antimicrobial surface coating was applied via electrostatic spray to patient rooms and common areas in three selected units at each hospital. Quantitative surface cultures were sent to an independent microbiology laboratory pre- and 11-weeks post-application to identify total bacterial colony-forming units (CFU). HAI outcomes from treatment and contemporaneous control units were assessed using National Healthcare Safety Network protocols for multidrug-resistant organism bloodstream infections (MDRO-BSI) and Clostridium difficile infections (CDI). We used Poisson regression models to compare HAI rates for treated and untreated units for 12-months before and after application of surface coating.

Results

Both hospitals showed statistically significant decreases in total bacterial CFU following application of the antimicrobial surface coating (64% and 75% decreases in Hospitals A and B, respectively, P < 0.0001). Across both hospitals, there was a 36% decline in pooled HAIs (hospital-onset MDRO-BSI + CDI) following application of surface coating in treated units (IRR = 0.64, 95% CI = 0.44–0.91), and no decline in HAIs over the same period in nontreated units (IRR = 1.20, 95% CI = 0.92–1.55).

Conclusion

Significant and persistent reductions in both microbial burden and associated HAIs occurred in units where surfaces were treated with antimicrobial surface coating, suggesting the potential for improved patient outcomes and reduced healthcare costs. Optimal implementation methods and long-term impact should be assessed with further study of this novel environmental control intervention.

Disclosures

All authors: No reported disclosures.

Evaluation of a program to improve hand hygiene in Kenyan hospitals through production and promotion of alcohol-based Handrub - 2012-2014

Although critical to prevent healthcare-associated infections, hand hygiene (HH) compliance is poor in resource-limited settings. In 2012, three Kenyan hospitals began onsite production of alcohol-based handrub (ABHR) and HH promotion. Our aim is to determine the impact of local production of ABHR on HH compliance and perceptions of ABHR. We observed 25,738 HH compliance opportunities and conducted 15 baseline and post-intervention focus group discussions. Hand Hygiene compliance increased from 28% (baseline) to 38% (post-intervention, p = 0.0003). Healthcare workers liked the increased accessibility of ABHR, but disliked its smell, feel, and sporadic availability. Onsite production and promotion of ABHR resulted in modest HH improvement. Enhancing the quality of ABHR and addressing logistical barriers could improve program impact.

Male-to-Female Sexual Transmission of Zika Virus-United States, January-April 2016

We report on 9 cases of male-to-female sexual transmission of Zika virus in the United States occurring January-April 2016. This report summarizes new information about both timing of exposure and symptoms of sexually transmitted Zika virus disease, and results of semen testing for Zika virus from 2 male travelers.

Strategies to prevent healthcare-associated infections through hand hygiene

Previously published guidelines provide comprehensive recommendations for hand hygiene in healthcare facilities. The intent of this document is to highlight practical recommendations in a concise format, update recommendations with the most current scientific evidence, and elucidate topics that warrant clarification or more robust research. Additionally, this document is designed to assist healthcare facilities in implementing hand hygiene adherence improvement programs, including efforts to optimize hand hygiene product use, monitor and report back hand hygiene adherence data, and promote behavior change. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.

Introduction to "A compendium of strategies to prevent healthcare-associated infections in acute care hospitals: 2014 updates"

Since the publication of "A Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals" in 2008, prevention of healthcare-associated infections (HAIs) has become a national priority. Despite improvements, preventable HAIs continue to occur. The 2014 updates to the Compendium were created to provide acute care hospitals with up-to-date, practical, expert guidance to assist in prioritizing and implementing their HAI prevention efforts. It is the product of a highly collaborative effort led by the Society for Healthcare Epidemiology of America (SHEA), the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise, including the Centers for Disease Control and Prevention (CDC), the Institute for Healthcare Improvement (IHI), the Pediatric Infectious Diseases Society (PIDS), the Society for Critical Care Medicine (SCCM), the Society for Hospital Medicine (SHM), and the Surgical Infection Society (SIS).

Strategies to Prevent Healthcare-Associated Infections through Hand Hygiene

Previously published guidelines provide comprehensive recommendations for hand hygiene in healthcare facilities. The intent of this document is to highlight practical recommendations in a concise format, update recommendations with the most current scientific evidence, and elucidate topics that warrant clarification or more robust research. Additionally, this document is designed to assist healthcare facilities in implementing hand hygiene adherence improvement programs, including efforts to optimize hand hygiene product use, monitor and report back hand hygiene adherence data, and promote behavior change. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.

Clinical Incidence of Methicillin-Resistant Staphylococcus aureus (MRSA) Colonization or Infection as a Proxy Measure for MRSA Transmission in Acute Care Hospitals

Background.

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) colonization or infection has been used as a proxy measure for MRSA transmission, but incidence calculations vary depending on whether active surveillance culture (ASC) data are included.

Objective.

To evaluate the relationship between incidences of MRSA colonization or infection calculated with and without ASCs in intensive care units and non-intensive care units.

Setting.

A Veterans Affairs medical center.

Methods.

From microbiology records, incidences of MRSA colonization or infection were calculated with and without ASC data. Correlation coefficients were calculated for the 2 measures, and Poisson regression was used to model temporal trends. A Poisson interaction model was used to test for differences in incidence trends modeled with and without ASCs.

Results.

The incidence of MRSA colonization or infection calculated with ASCs was 4.9 times higher than that calculated without ASCs. Correlation coefficients for incidences with and without ASCs were 0.42 for intensive care units, 0.59 for non-intensive care units, and 0.48 hospital-wide. Trends over time for the hospital were similar with and without ASCs (incidence rate ratio with ASCs, 0.95 [95% confidence interval, 0.93-0.97]; incidence rate ratio without ASCs, 0.95 [95% confidence interval, 0.92-0.99]; P = .68). Without ASCs, 35% of prevalent cases were falsely classified as incident.

Conclusions.

At 1 Veterans Affairs medical center, the incidence of MRSA colonization or infection calculated solely on the basis of clinical culture results commonly misclassified incident cases and underestimated incidence, compared with measures that included ASCs; however, temporal changes were similar. These findings suggest that incidence measured without ASCs may not accurately reflect the magnitude of MRSA transmission but may be useful for monitoring transmission trends over time, a crucial element for evaluating the impact of prevention activities.

Evaluation of International Classification of Diseases, Ninth Revision, Clinical Modification Codes for Reporting Methicillin-Resistant Staphylococcus aureus Infections at a Hospital in Illinois

Background.

States, including Illinois, have passed legislation mandating the use of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for reporting healthcare-associated infections, such as methicillin-resistant Staphylococcus aureus (MRSA).

Objective.

To evaluate the sensitivity of ICD-9-CM code combinations for detection of MRSA infection and to understand implications for reporting.

Methods.

We reviewed discharge and microbiology databases from July through August of 2005, 2006, and 2007 for ICD-9-CM codes or microbiology results suggesting MRSA infection at a tertiary care hospital near Chicago, Illinois. Medical records were reviewed to confirm MRSA infection. Time from admission to first positive MRSA culture result was evaluated to identify hospital-onset MRSA (HO-MRSA) infections. The sensitivity of MRSA code combinations for detecting confirmed MRSA infections was calculated using all codes present in the discharge record (up to 15); the effect of reviewing only 9 diagnosis codes, the number reported to the Centers for Medicare and Medicaid Services, was also evaluated. The sensitivity of the combination of diagnosis codes for detection of HO-MRSA infections was compared with that for community-onset MRSA (CO-MRSA) infections.

Results.

We identified 571 potential MRSA infections with the use of screening criteria; 403 (71%) were confirmed MRSA infections, of which 61 (15%) were classified as HO-MRSA. The sensitivity of MRSA code combinations was 59% for all confirmed MRSA infections when 15 diagnoses were reviewed compared with 31% if only 9 diagnoses were reviewed (P &lt; .001). The sensitivity of code combinations was 33% for HO-MRSA infections compared with 62% for CO-MRSA infections (P &lt; .001).

Conclusions.

Limiting analysis to 9 diagnosis codes resulted in low sensitivity. Furthermore, code combinations were better at revealing CO-MRSA infections than HO-MRSA infections. These limitations could compromise the validity of ICD-9-CM codes for interfacility comparisons and for reporting of healthcare-associated MRSA infections.

Impact of Electronic Surveillance on Isolation Practices

Objective.

To assess the impact of an electronic surveillance system on isolation practices and rates of methicillin-resistant Staphylococcus aureus (MRSA).

Design.

A pre-post test intervention.

Setting.

Inpatient units (except psychiatry and labor and delivery) in 4 New York City hospitals.

Patients.

All patients for whom isolation precautions were indicated, May 2009–December 2011.

Methods.

Trained observers assessed isolation sign postings, availability of isolation carts, and staff use of personal protective equipment (PPE). Infection rates were obtained from the infection control department. Regression analyses were used to examine the association between the surveillance system, infection prevention practices, and MRSA infection rates.

Results.

A total of 54,159 isolation days and 7,628 staff opportunities for donning PPE were observed over a 31-month period. Odds of having an appropriate sign posted were significantly higher after intervention than before intervention (odds ratio [OR], 1.10 [95% confidence interval {CI}, 1.01–1.20]). Relative to baseline, postintervention sign posting improved significantly for airborne and droplet precautions but not for contact precautions. Sign posting improved for vancomycin-resistant enterococci (OR, 1.51 [95% CI, 1.23–1.86]; P = .0001), Clostridium difficile (OR, 1.59 [95% CI, 1.27–2.02]; P = .00005), and Acinetobacter baumannii (OR, 1.41 [95% CI, 1.21–1.64]; P = .00001) precautions but not for MRSA precautions (OR, 1.11 [95% CI, 0.89–1.39]; P = .36). Staff and visitor adherence to PPE remained low throughout the study but improved from 29.1% to 37.0% after the intervention (OR, 1.14 [95% CI, 1.01–1.29]). MRSA infection rates were not significantly different after the intervention.

Conclusions.

An electronic surveillance system resulted in small but statistically significant improvements in isolation practices but no reductions in infection rates over the short term. Such innovations likely require considerable uptake time.

Sustained Reduction in the Clinical Incidence of Methicillin-Resistant Staphylococcus aureus Colonization or Infection Associated with a Multifaceted Infection Control Intervention

Objective.

To assess the impact and sustainability of a multifaceted intervention to prevent methicillin-resistant Staphylococcus aureus (MRSA) transmission implemented in 3 chronologically overlapping phases at 1 hospital.

Design.

Interrupted time-series analyses.

Setting.

A Veterans Affairs hospital in the northeastern United States.

Patients and Participants.

Individuals admitted to acute care units from October 1, 1999, through September 30, 2008. To calculate the monthly clinical incidence of MRSA colonization or infection, the number of MRSA-positive cultures obtained from a clinical site more than 48 hours after admission among patients with no MRSA-positive clinical cultures during the previous year was divided by patient-days at risk. Secondary outcomes included clinical incidence of methicillin-sensitive S. aureus colonization or infection and incidence of MRSA bloodstream infections.

Interventions.

The intervention—implemented in a surgical ward beginning October 2001, in a surgical intensive care unit beginning October 2003, and in all acute care units beginning July 2005—included systems and behavior change strategies to increase adherence to infection control precautions (eg, hand hygiene and active surveillance culturing for MRSA).

Results.

Hospital-wide, the clinical incidence of MRSA colonization or infection decreased after initiation of the intervention in 2001, compared with the period before intervention (P = .002), and decreased by 61% (P < .001) in the 7-year postintervention period. In the postintervention period, the hospital-wide incidence of MRSA bloodstream infection decreased by 50% (P = .02), and the proportion of S. aureus isolates that were methicillin resistant decreased by 30% (P < .001).

Conclusions.

Sustained decreases in hospital-wide clinical incidence of MRSA colonization or infection, incidence of MRSA bloodstream infection, and proportion of S. aureus isolates resistant to methicillin followed implementation of a multifaceted prevention program at one Veterans Affairs hospital. Findings suggest that interventions designed to prevent transmission can impact endemic antimicrobial resistance problems.

Introduction to "A Compendium of Strategies To Prevent Healthcare-Associated Infections in Acute Care Hospitals: 2014 updates"

Since the publication of "A Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals" in 2008, prevention of healthcare-associated infections (HAIs) has become a national priority. Despite improvements, preventable HAIs continue to occur. The 2014 updates to the Compendium were created to provide acute care hospitals with up-to-date, practical, expert guidance to assist in prioritizing and implementing their HAI prevention efforts. It is the product of a highly collaborative effort led by the Society for Healthcare Epidemiology of America (SHEA), the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise, including the Centers for Disease Control and Prevention (CDC), the Institute for Healthcare Improvement (IHI), the Pediatric Infectious Diseases Society (PIDS), the Society for Critical Care Medicine (SCCM), the Society for Hospital Medicine (SHM), and the Surgical Infection Society (SIS).

Surveillance for respiratory health care-associated infections among inpatients in 3 Kenyan hospitals, 2010-2012

BACKGROUND

Although health care-associated infections are an important cause of morbidity and mortality worldwide, the epidemiology and etiology of respiratory health care-associated infections (rHAIs) have not been documented in Kenya. In 2010, the Ministry of Health, Kenya Medical Research Institute, and Centers for Disease Control and Prevention initiated surveillance for rHAIs at 3 hospitals.

METHODS

At each hospital, we surveyed intensive care units (ICUs), pediatric wards, and medical wards to identify patients with rHAIs, defined as any hospital-onset (≥3 days after admission) fever (≥38°C) or hypothermia (<35°C) with concurrent signs or symptoms of acute respiratory infection. Nasopharyngeal and oropharyngeal specimens were collected from these patients and tested by real-time reverse transcription polymerase chain reaction for influenza and 7 other viruses.

RESULTS

From April 2010-September 2012, of the 379 rHAI cases, 60.7% were men and 57.3% were children <18 years old. The overall incidence of rHAIs was 9.2 per 10,000 patient days, with the highest incidence in the ICUs. Of all specimens analyzed, 45.7% had at least 1 respiratory virus detected; 92.2% of all positive viral specimens were identified in patients <18 years old.

CONCLUSION

We identified rHAIs in all ward types under surveillance in Kenyan hospitals. Viruses may have a substantial role in these infections, particularly among pediatric populations. Further research is needed to refine case definitions and understand rHAIs in ICUs.

Perspectives on Federal Funding for State Health Care-Associated Infection Programs: Achievements, Barriers, and Implications for Sustainability

In September 2009, federal funding for health care-associated infection (HAI) program development was dispersed through a cooperative agreement to 51 state and territorial health departments. From July to September 2011, 69 stakeholders from six states-including state health department employees, representatives from partner organizations, and health care facility employees-were interviewed to assess state HAI program achievements, implementation barriers, and strategies for sustainability. Respondents most frequently cited enhanced HAI surveillance as a program achievement and resource constraints as an implementation barrier. To sustain programs, respondents recommended ongoing support for HAI prevention activities, improved surveillance processes, and maintenance of partnerships. Findings suggest that state-level HAI program growth was achieved during the cooperative agreement but that maintenance of programs faces challenges.

Enhancement of health department capacity for health care-associated infection prevention through Recovery Act-funded programs

OBJECTIVES

We evaluated capacity built and outcomes achieved from September 1, 2009, to December 31, 2011, by 51 health departments (HDs) funded through the American Recovery and Reinvestment Act (ARRA) for health care-associated infection (HAI) program development.

METHODS

We defined capacity for HAI prevention at HDs by 25 indicators of activity in 6 categories: staffing, partnerships, training, technical assistance, surveillance, and prevention. We assessed state-level infection outcomes by modeling quarterly standardized infection ratios (SIRs) for device- and procedure-associated infections with longitudinal regression models.

RESULTS

With ARRA funds, HDs created 188 HAI-related positions and supported 1042 training programs, 53 surveillance data validation projects, and 60 prevention collaboratives. All states demonstrated significant declines in central line-associated bloodstream and surgical site infections. States that implemented ARRA-funded catheter-associated urinary tract infection prevention collaboratives showed significantly greater SIR reductions over time than states that did not (P = .02).

CONCLUSIONS

ARRA-HAI funding substantially improved HD capacity to reduce HAIs not targeted by other national efforts, suggesting that HDs can play a critical role in addressing emerging or neglected HAIs.

Incidence and pathogen distribution of healthcare-associated infections in pilot hospitals in Egypt

OBJECTIVE

To report type and rates of healthcare-associated infections (HAIs) as well as pathogen distribution and antimicrobial resistance patterns from a pilot HAI surveillance system in Egypt.

METHODS

Prospective surveillance was conducted from April 2011 through March 2012 in 46 intensive care units (ICUs) in Egypt. Definitions were adapted from the Centers for Disease Control and Prevention's National Healthcare Safety Network. Trained healthcare workers identified HAIs and recorded data on clinical symptoms and up to 4 pathogens. A convenience sample of clinical isolates was tested for antimicrobial resistance at a central reference laboratory. Multidrug resistance was defined by international consensus criteria.

RESULTS

ICUs from 11 hospitals collected 90,515 patient-days of surveillance data. Of 472 HAIs identified, 47% were pneumonia, 22% were bloodstream infections, and 15% were urinary tract infections; case fatality among HAI case patients was 43%. The highest rate of device-associated infections was reported for ventilator-associated pneumonia (pooled mean rate, 7.47 cases per 1,000 ventilator-days). The most common pathogens reported were Acinetobacter species (21.8%) and Klebsiella species (18.4%). All Acinetobacter isolates tested (31/31) were multidrug resistant, and 71% (17/24) of Klebsiella pneumoniae isolates were extended-spectrum β-lactamase producers.

CONCLUSIONS

Infection control priorities in Egypt should include preventing pneumonia and preventing infections due to antimicrobial-resistant pathogens.

Automated hand hygiene count devices may better measure compliance than human observation

BACKGROUND

Hand hygiene is considered a critical factor in the prevention of health care-associated infections, and there have been many studies on ways to measure hand hygiene compliance.

OBJECTIVE

Our objective was to evaluate the utility of estimating hand hygiene compliance using automated count technology versus direct human observation before and after a feedback intervention. We used a before and after quasi-experimental study over 30 weeks, in the setting of one 12-bed neurocare intensive care unit (NCICU) and one 15-bed cardiac intensive care unit (CCU) in a university, tertiary care hospital.

METHODS

We assessed hand hygiene through a quasi-experimental study comparing estimated compliance using automated count technology and direct observation by a secret shopper with a feedback intervention at month 3. We used Poisson segmented regression and χ(2) tests to compare trends before and after the intervention.

RESULTS

Over 30 weeks, we collected 424,682 dispenser counts and 338 hours of human observations that included 1,783 room entries. Electronic hand hygiene dispenser counts increased significantly in the post-intervention period relative to the pre-intervention period (average count/patient-day increased 22.7 in the NCICU and 7.3 in the CCU, both P < .001), but direct observation of compliance did not change significantly (percent compliant increased by 2.9% in the NCICU and decreased by 6.7% in the CCU, P = .47 and P = .07, respectively).

CONCLUSION

Passive electronic monitoring of hand hygiene dispenser counts does not closely correlate with direct human observation and was more responsive than observation to a feedback intervention.

Monitoring hand hygiene via human observers: how should we be sampling?

OBJECTIVE

To explore how hand hygiene observer scheduling influences the number of events and unique individuals observed.

DESIGN

We deployed a mobile sensor network to capture detailed movement data for 6 categories of healthcare workers over a 2-week period.

SETTING

  University of Iowa Hospital and Clinic medical intensive care unit (ICU).

METHODS

We recorded 33,721 time-stamped healthcare worker entries to and exits from patient rooms and considered each entry or exit to be an opportunity for hand hygiene. Architectural drawings were used to derive 4 optimal line-of-sight placements for observers. We ran simulations for different observer movement schedules, all with a budget of 1 hour of total observation time. We considered observation times of 1-15, 15-30, 30, and 60 minutes per station. We stochastically generated healthcare worker hand hygiene compliance on the basis of all data and recorded the total unit compliance as it would be reported by each simulated observer.

RESULTS

Considering a 60-minute total observation period, aggregate simulated observers captured 1.7% of the average total number of opportunities per day at best and 0.5% at worst. The 1-15-minute schedule captures, on average, 16% fewer events than does the 60-minute (ie, static) schedule, but it samples 17% more unique individuals. The 1-15-minute schedule also provides the best estimator of compliance for the duration of the shift, with a mean standard deviation of 17%, compared with 23% for the 60-minute schedule.

CONCLUSIONS

Our results show that observations are sensitive to different observers' schedules and suggest the importance of using data-driven approaches to schedule hand hygiene audits.

Healthcare personnel perceptions of hand hygiene monitoring technology

OBJECTIVE

To assess healthcare personnel (HCP) perceptions regarding implementation of sensor-based electronic systems for automated hand hygiene adherence monitoring.

DESIGN

Using a mixed-methods approach, structured focus groups were designed to elicit quantitative and qualitative responses on familiarity, comfort level, and perceived impact of sensor-based hand hygiene adherence monitoring.

SETTING

A university hospital, a Veterans Affairs hospital, and a community hospital in the Midwest.

PARTICIPANTS

Focus groups were homogenous by HCP type, with separate groups held for leadership, midlevel management, and frontline personnel at each hospital.

RESULTS

Overall, 89 HCP participated in 10 focus groups. Levels of familiarity and comfort with electronic oversight technology varied by HCP type; when compared with frontline HCP, those in leadership positions were significantly more familiar with ([Formula: see text]) and more comfortable with ([Formula: see text]) the technology. The most common concerns cited by participants across groups included lack of accuracy in the data produced, such as the inability of the technology to assess the situational context of hand hygiene opportunities, and the potential punitive use of data produced. Across groups, HCP had decreased tolerance for electronic collection of spatial-temporal data, describing such oversight as Big Brother.

CONCLUSIONS

While substantial concerns were expressed by all types of HCP, participants' recommendations for effective implementation of electronic oversight technologies for hand hygiene monitoring included addressing accuracy issues before implementation and transparent communication with frontline HCP about the intended use of the data.

Estimated risk of human immunodeficiency virus and hepatitis C virus infection among potential organ donors from 17 organ procurement organizations in the United States

To prevent unintentional transmission of bloodborne pathogens through organ transplantation, organ procurement organizations (OPOs) screen potential donors by serologic testing to identify human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection. Newly acquired infection, however, may be undetectable by serologic testing. Our objective was to estimate the incidence of undetected infection among potential organ donors and to assess the significance of risk reductions conferred by nucleic acid testing (NAT) versus serology alone. We calculated prevalence of HIV and HCV-stratified by OPO risk designation-in 13,667 potential organ donors managed by 17 OPOs from 1/1/2004 to 7/1/2008. We calculated incidence of undetected infection using the incidence-window period approach. The prevalence of HIV was 0.10% for normal risk potential donors and 0.50% for high risk potential donors; HCV prevalence was 3.45% and 18.20%, respectively. For HIV, the estimated incidence of undetected infection by serologic screening was 1 in 50,000 for normal risk potential donors and 1 in 11,000 for high risk potential donors; for HCV, undetected incidence by serologic screening was 1 in 5000 and 1 in 1000, respectively. Projected estimates of undetected infection with NAT screening versus serology alone suggest that NAT screening could significantly reduce the rate of undetected HCV for all donor risk strata.

Are abusive fractures in young children becoming less common? Changes over 24 years

OBJECTIVE

To determine whether the proportion of fractures rated as abusive in children <36 months of age evaluated at a regional pediatric hospital increased over a 24-year period from 1979 to 2002. Fractures were chosen as an example of serious injuries in young children.

METHODS

Medical records were abstracted for all children <36 months of age who were seen at a single pediatric hospital with a fracture during three time periods: 1979-1983, 1991-1994, and 1999-2002. After reviewing the abstracted and radiographic information, two clinicians (one an expert on child abuse) and two pediatric radiologists each rated the likelihood of abuse using explicit criteria and a seven-point scale from definite abuse to definite unintentional injury. Ratings were done independently; when disagreements occurred, the case was discussed, and a joint rating was agreed upon, if possible. The proportions of cases rated as abuse were compared over the three time periods, and logistic regression was used to calculate adjusted odds ratios (OR).

RESULTS

In the early, middle, and late samples, there were 200, 240, and 232 children, respectively, with fractures. The proportion of cases rated as abuse decreased from 22.5% in the early period to 10.0% in the middle period and was 10.8% in the late period (p<.001). When comparing the odds of abuse in the middle and late groups to the odds of abuse in the early group (controlling for age, gender, ethnicity, type of medical insurance, and site of pediatric care), the adjusted ORs were .31 (95% CI=.15, .62) for the middle group and .45 (95% CI=.23, .86) for the late group. Thus, the odds of a given case being rated as abuse decreased by over 50% from the early period to the middle and late time periods. No statistically significant difference was found when comparing the odds of abuse for the middle group to those of the late group, OR: 1.46 (95% CI=.69, 3.08).

CONCLUSIONS

The proportion of abusive fractures in young children decreased substantially from 1979-1983 to 1991-1994 and 1999-2002 at a major pediatric hospital. We speculate that this decrease may reflect early recognition of less serious forms of maltreatment and the availability of services to high-risk families.