BACKGROUND: While there is evidence that COVID-19 vaccination protects against development of post-COVID conditions (PCC) after severe infection data are limited on whether vaccination reduces the risk after cases of less-severe non-hospitalized COVID-19 disease with more recent SARS-CoV-2 variant viruses. This study assessed whether COVID-19 vaccination was protective against subsequent development of PCC in persons with predominantly mild initial infections during both Delta and Omicron variant predominance. METHODS: This study utilized a case-control design, nested within the HEROES-RECOVER cohort. Participants aged ≥18 years with PCR-confirmed SARS-CoV-2 infection between 6/28/2021 and 9/14/2022 were surveyed for PCC, defined by symptoms lasting >1 month after initial infection Cases were participants self-reporting PCC and controls were participants that did not self-report PCC. The exposure was mRNA COVID-19 vaccination (2 or 3 monovalent doses) versus no COVID-19 vaccination. Logistic regression was used to compare the odds of PCC among vaccinated and unvaccinated persons; additional analyses evaluating PCC subtypes were also performed. RESULTS: A total of 936 participants with documented SARS-CoV-2 infection were included; of these 23.6% (221) reported PCC and 83.3% (779) were vaccinated. Participants who received a 3rd COVID-19 monovalent mRNA dose prior to infection had lower odds of PCC-related gastrointestinal, neurological, and other symptoms compared to unvaccinated participants (aOR: 0.37; 95% CI: 0.16-0.85; aOR: 0.56; 95% CI: 0.32-0.97; aOR:0.48; 95% CI: 0.25-0.91). CONCLUSIONS: COVID-19 vaccination protected against development of PCC among persons with mild infection during both Delta and Omicron variant predominance, supporting vaccination as an important tool for PCC prevention.

BACKGROUND: Previous estimates of vaccine effectiveness (VE) against asymptomatic influenza virus infection based on seroconversion have varied widely and may be biased. We estimated 2022-2023 influenza VE against illness and asymptomatic infection in a prospective cohort. METHODS: In the HEROES-RECOVER cohort, adults at increased occupational risk of influenza exposure across 7 US sites provided weekly symptom reports and nasal swabs for reverse transcription-polymerase chain reaction (RT-PCR) influenza testing. Laboratory-confirmed influenza virus infections were classified as symptomatic (≥1 symptom) or asymptomatic during the week of testing. Participants reported demographic information and vaccination through surveys; most sites verified vaccination through medical record and immunization registry review. Person-time was calculated as days from the site-specific influenza season start (September-October 2022) through date of infection, study withdrawal, or season end (May 2023). We compared influenza incidence among vaccinated versus unvaccinated participants overall, by symptom status, and by influenza A subtype, using Cox proportional hazards regression adjusted for site and occupation. We estimated VE as (1 - adjusted hazard ratio) × 100%. RESULTS: In total, 269 of 3785 (7.1%) participants had laboratory-confirmed influenza, including 263 (98%) influenza A virus infections and 201 (75%) symptomatic illnesses. Incidence of laboratory-confirmed influenza illness among vaccinated versus unvaccinated participants was 23.7 and 33.2 episodes per 100 000 person-days, respectively (VE: 38%; 95% CI: 15%-55%). Incidence of asymptomatic influenza virus infection was 8.0 versus 11.6 per 100 000 (VE: 13%; 95% CI: -47%, 49%). CONCLUSIONS: Vaccination reduced incidence of symptomatic but not asymptomatic influenza virus infection, suggesting that influenza vaccination attenuates progression from infection to illness.

Households are a primary setting for transmission of SARS-CoV-2. We examined the role of prior SARS-CoV-2 immunity on the risk of infection in household close contacts. Households in the United States with an individual who tested positive for SARS-CoV-2 during September 2021-May 2023 were enrolled if the index case's illness began ≤6 days prior. Household members had daily self-collected nasal swabs tested by RT-PCR for SARS-CoV-2. The effects of prior SARS-CoV-2 immunity (vaccination, prior infection, or hybrid immunity) on SARS-CoV-2 infection risk among household contacts were assessed by robust, clustered multivariable Poisson regression. Of 1,532 contacts (905 households), 8% had immunity from prior infection alone, 51% from vaccination alone, 29% hybrid immunity, and 11% had no prior immunity. Sixty percent of contacts tested SARS-CoV-2-positive during follow-up. The adjusted risk of SARS-CoV-2 infection was lowest among contacts with vaccination and prior infection (aRR: 0.81, 95% CI: 0.70, 0.93, compared with contacts with no prior immunity) and was lowest when the last immunizing event occurred ≤6 months before COVID-19 affected the household (aRR: 0.69, 95% CI: 0.57, 0.83). In high-transmission settings like households, immunity from COVID-19 vaccination and prior infection was synergistic in protecting household contacts from SARS-CoV-2 infection.

Hybrid immunity, as a result of infection and vaccination to SARS-CoV-2, has been well studied in adults but limited evidence is available in children. We evaluated the antibody responses to primary SARS-CoV-2 infection among vaccinated and unvaccinated children aged ≥ 5 years. METHODS: A longitudinal cohort study of children aged ≥ 5 was conducted during August 2021-August 2022, at sites in Arizona, Texas, Utah, and Florida. Children submitted weekly nasal swabs for PCR testing and provided sera 14-59 days after PCR-confirmed SARS-CoV-2 infection. Antibodies were measured by ELISA against the receptor-binding domain (RBD) and S2 domain of ancestral Spike (WA1), in addition to Omicron (BA.2) RBD, following infection in children, with and without prior monovalent ancestral mRNA COVID-19 vaccination. RESULTS: Among the 257 participants aged 5 to 18 years, 166 (65%) had received at least two mRNA COVID-19 vaccine doses ≥ 14 days prior to infection. Of these, 53 occurred during Delta predominance, with 37 (70%) unvaccinated at the time of infection. The remaining 204 infections occurred during Omicron predominance, with 53 (26%) participants unvaccinated. After adjusting for weight, age, symptomatic infection, and gender, significantly higher mean RBD AUC values were observed among the vaccinated group compared to the unvaccinated group for both WA1 and Omicron (p < 0.0001). A smaller percentage of vaccinated children reported fever during illness, with 55 (33%) reporting fever compared to 44 (48%) unvaccinated children reporting fever (p = 0.021). CONCLUSIONS: Children with vaccine-induced immunity at the time of SARS-CoV-2 infection had higher antibody levels during convalescence and experienced less fever compared to unvaccinated children during infection.

BACKGROUND: Nirmatrelvir/ritonavir (N/R) reduces severe outcomes from coronavirus disease 2019 (COVID-19); however, rebound after treatment has been reported. We compared symptom and viral dynamics in individuals with COVID-19 who completed N/R treatment and similar untreated individuals. METHODS: We identified symptomatic participants who tested severe acute respiratory syndrome coronavirus 2-positive and were N/R eligible from a COVID-19 household transmission study. Index cases from ambulatory settings and their households contacts were enrolled. We collected daily symptoms, medication use, and respiratory specimens for quantitative polymerase chain reaction for 10 days during March 2022-May 2023. Participants who completed N/R treatment (treated) were propensity score matched to untreated participants. We compared symptom rebound, viral load (VL) rebound, average daily symptoms, and average daily VL by treatment status measured after N/R treatment completion or 7 days after symptom onset if untreated. RESULTS: Treated (n = 130) and untreated participants (n = 241) had similar baseline characteristics. After treatment completion, treated participants had greater occurrence of symptom rebound (32% vs 20%; P = .009) and VL rebound (27% vs 7%; P < .001). Average daily symptoms were lower among treated participants without symptom rebound (1.0 vs 1.6; P < .01) but not statistically lower with symptom rebound (3.0 vs 3.4; P = .5). Treated participants had lower average daily VLs without VL rebound (0.9 vs 2.6; P < .01) but not statistically lower with VL rebound (4.8 vs 5.1; P = .7). CONCLUSIONS: Individuals who completed N/R treatment experienced fewer symptoms and lower VL but rebound occured more often compared with untreated individuals. Providers should prescribe N/R, when indicated, and communicate rebound risk to patients.

As population immunity to SARS-CoV-2 evolves and new variants emerge, the role and accuracy of antigen tests remain active questions. To describe recent test performance, the detection of SARS-CoV-2 by antigen testing was compared with that by reverse transcription-polymerase chain reaction (RT-PCR) and viral culture testing during November 2022-May 2023. Participants who were enrolled in a household transmission study completed daily symptom diaries and collected two nasal swabs (tested for SARS-CoV-2 via RT-PCR, culture, and antigen tests) each day for 10 days after enrollment. Among participants with SARS-CoV-2 infection, the percentages of positive antigen, RT-PCR, and culture results were calculated each day from the onset of symptoms or, in asymptomatic persons, from the date of the first positive test result. Antigen test sensitivity was calculated using RT-PCR and viral culture as references. The peak percentage of positive antigen (59.0%) and RT-PCR (83.0%) results occurred 3 days after onset, and the peak percentage of positive culture results (52%) occurred 2 days after onset. The sensitivity of antigen tests was 47% (95% CI = 44%-50%) and 80% (95% CI = 76%-85%) using RT-PCR and culture, respectively, as references. Clinicians should be aware of the lower sensitivity of antigen testing compared with RT-PCR, which might lead to false-negative results. This finding has implications for timely initiation of SARS-CoV-2 antiviral treatment, when early diagnosis is essential; clinicians should consider RT-PCR for persons for whom antiviral treatment is recommended. Persons in the community who are at high risk for severe COVID-19 illness and eligible for antiviral treatment should seek testing from health care providers with the goal of obtaining a more sensitive diagnostic test than antigen tests (i.e., an RT-PCR test).

BACKGROUND: There are limited data on whether hybrid immunity differs by count and order of immunity-conferring events (SARS-CoV-2 infection or COVID-19 vaccination). From a cohort of health care personnel, first responders, and other frontline workers in six US states, we examined heterogeneity of the effect of hybrid immunity on SARS-CoV-2 antibody levels. METHODS: Exposures included event-count (sum of infections and vaccine doses) and event-order, categorized into seven permutations of vaccination and/or infection. Outcome was level of serum binding antibodies against receptor binding domain (RBD) of the ancestral SARS-CoV-2 spike protein (total RBD-binding Ig), measured by enzyme-linked immunosorbent assay. Mean antibody levels were examined up to 365 days after each of the 1st-7th events. RESULTS: Analysis included 5,793 participants measured from August 7, 2020 to April 15, 2023. Hybrid immunity from infection before one or two vaccine doses elicited modestly superior antibody responses after the 2nd and 3rd events (compared to infections or vaccine-doses alone). This superiority was not evident after the 4th and 5th events (additional doses). Among adults infected before vaccination, adjusted geometric mean ratios (95% CI) of anti-RBD early response (versus vaccinated-only) were 1.23 (1.14-1.33), 1.09 (1.03-1.14), 0.87 (0.81-0.94), and 0.99 (0.85-1.15) after the 2nd-5th events, respectively. Post-vaccination infections elicited superior responses: adjusted geometric mean ratios (95% CI) of anti-RBD early response (versus vaccinated-only) were: 0.93 (0.75-1.17), 1.11 (1.06-1.16), 1.17 (1.11-1.24), and 1.20 (1.07-1.34) after the 2nd-5th events, respectively. CONCLUSIONS AND RELEVANCE: Findings reflecting heterogeneity in antibody levels by permutations of infection and vaccination history could inform COVID-19 vaccination policy.

IMPORTANCE: Bivalent mRNA COVID-19 vaccines were recommended in the US for children and adolescents aged 12 years or older on September 1, 2022, and for children aged 5 to 11 years on October 12, 2022; however, data demonstrating the effectiveness of bivalent COVID-19 vaccines are limited. OBJECTIVE: To assess the effectiveness of bivalent COVID-19 vaccines against SARS-CoV-2 infection and symptomatic COVID-19 among children and adolescents. DESIGN, SETTING, AND PARTICIPANTS: Data for the period September 4, 2022, to January 31, 2023, were combined from 3 prospective US cohort studies (6 sites total) and used to estimate COVID-19 vaccine effectiveness among children and adolescents aged 5 to 17 years. A total of 2959 participants completed periodic surveys (demographics, household characteristics, chronic medical conditions, and COVID-19 symptoms) and submitted weekly self-collected nasal swabs (irrespective of symptoms); participants submitted additional nasal swabs at the onset of any symptoms. EXPOSURE: Vaccination status was captured from the periodic surveys and supplemented with data from state immunization information systems and electronic medical records. MAIN OUTCOME AND MEASURES: Respiratory swabs were tested for the presence of the SARS-CoV-2 virus using reverse transcriptase-polymerase chain reaction. SARS-CoV-2 infection was defined as a positive test regardless of symptoms. Symptomatic COVID-19 was defined as a positive test and 2 or more COVID-19 symptoms within 7 days of specimen collection. Cox proportional hazards models were used to estimate hazard ratios for SARS-CoV-2 infection and symptomatic COVID-19 among participants who received a bivalent COVID-19 vaccine dose vs participants who received no vaccine or monovalent vaccine doses only. Models were adjusted for age, sex, race, ethnicity, underlying health conditions, prior SARS-CoV-2 infection status, geographic site, proportion of circulating variants by site, and local virus prevalence. RESULTS: Of the 2959 participants (47.8% were female; median age, 10.6 years [IQR, 8.0-13.2 years]; 64.6% were non-Hispanic White) included in this analysis, 25.4% received a bivalent COVID-19 vaccine dose. During the study period, 426 participants (14.4%) had laboratory-confirmed SARS-CoV-2 infection. Among these 426 participants, 184 (43.2%) had symptomatic COVID-19, 383 (89.9%) were not vaccinated or had received only monovalent COVID-19 vaccine doses (1.38 SARS-CoV-2 infections per 1000 person-days), and 43 (10.1%) had received a bivalent COVID-19 vaccine dose (0.84 SARS-CoV-2 infections per 1000 person-days). Bivalent vaccine effectiveness against SARS-CoV-2 infection was 54.0% (95% CI, 36.6%-69.1%) and vaccine effectiveness against symptomatic COVID-19 was 49.4% (95% CI, 22.2%-70.7%). The median observation time after vaccination was 276 days (IQR, 142-350 days) for participants who received only monovalent COVID-19 vaccine doses vs 50 days (IQR, 27-74 days) for those who received a bivalent COVID-19 vaccine dose. CONCLUSION AND RELEVANCE: The bivalent COVID-19 vaccines protected children and adolescents against SARS-CoV-2 infection and symptomatic COVID-19. These data demonstrate the benefit of COVID-19 vaccine in children and adolescents. All eligible children and adolescents should remain up to date with recommended COVID-19 vaccinations.

Since the initial publication of A Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals in 2008, the prevention of healthcare-associated infections (HAIs) has continued to be a national priority. Progress in healthcare epidemiology, infection prevention, antimicrobial stewardship, and implementation science research has led to improvements in our understanding of effective strategies for HAI prevention. Despite these advances, HAIs continue to affect ∼1 of every 31 hospitalized patients, leading to substantial morbidity, mortality, and excess healthcare expenditures, and persistent gaps remain between what is recommended and what is practiced.The widespread impact of the coronavirus disease 2019 (COVID-19) pandemic on HAI outcomes in acute-care hospitals has further highlighted the essential role of infection prevention programs and the critical importance of prioritizing efforts that can be sustained even in the face of resource requirements from COVID-19 and future infectious diseases crises.The Compendium: 2022 Updates document provides acute-care hospitals with up-to-date, practical expert guidance to assist in prioritizing and implementing HAI prevention efforts. It is the product of a highly collaborative effort led by the Society for Healthcare Epidemiology of America (SHEA), the Infectious Disease Society of America (IDSA), the Association for Professionals in Infection Control and Epidemiology (APIC), the American Hospital Association (AHA), and The Joint Commission, with major contributions from representatives of organizations and societies with content expertise, including the Centers for Disease Control and Prevention (CDC), the Pediatric Infectious Disease Society (PIDS), the Society for Critical Care Medicine (SCCM), the Society for Hospital Medicine (SHM), the Surgical Infection Society (SIS), and others.

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous throughout the United States. Previous studies have shown PFAS exposure to be associated with a reduced immune response. However, the relationship between serum PFAS and antibody levels following SARS-CoV-2 infection or COVID-19 vaccination has not been examined. We examined differences in peak immune response and the longitudinal decline of antibodies following SARS-CoV-2 infection and COVID-19 vaccination by serum PFAS levels in a cohort of essential workers in the United States. We measured serum antibodies using an in-house semi-quantitative enzyme-linked immunosorbent assay (ELISA). Two cohorts contributed blood samples following SARS-CoV-2 infection or COVID-19 vaccination. We used linear mixed regression models, adjusting for age, race/ethnicity, gender, presence of chronic conditions, location, and occupation, to estimate differences in immune response with respect to serum PFAS levels. Our study populations included 153 unvaccinated participants that contributed 316 blood draws over a 14-month period following infection, and 860 participants and 2451 blood draws over a 12-month period following vaccination. Higher perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA) concentrations were associated with a lower peak antibody response after infection (p = 0.009, 0.031, 0.015). Higher PFOS, perfluorooctanoic acid (PFOA), PFHxS, and PFNA concentrations were associated with slower declines in antibodies over time after infection (p = 0.003, 0.014, 0.026, 0.025). PFOA, PFOS, PFHxS, and PFNA serum concentrations prior to vaccination were not associated with differences in peak antibody response after vaccination or with differences in decline of antibodies over time after vaccination. These results suggest that elevated PFAS may impede potential immune response to SARS-CoV-2 infection by blunting peak antibody levels following infection; the same finding was not observed for immune response to vaccination.

BACKGROUND: The PROTECT study is a longitudinal cohort study initiated in July 2021 with weekly testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 4 states: Arizona, Florida, exas, and Utah. This study aims to examine vaccine-elicited antibody response against postvaccination SARS-CoV-2 infections. METHODS: Children aged 5-11 years had serum collected 14-59 days after their second dose of monovalent Pfizer-BioNTech coronavirus disease 2019 messenger RNA vaccine. Vaccine-elicited antibodies were measured using the area under the curve (AUC) and end-point titer using enzyme-linked immunosorbent assay (receptor-binding domain [RBD] and S2) and surrogate neutralization assays against ancestral (WA1) and Omicron (BA.2). RESULTS: 79 vaccinated participants (33 [41.7%] female; median age, 8.8 years [standard deviation, 1.9 years]), 48 (60.8%) were from Tucson, Arizona; 64 (81.0%) were non-Hispanic white; 63 (80.8%) attended school in person; 68 (86.1%) did not have any chronic conditions; and 47 (59.5%) were infected after vaccination. Uninfected children had higher AUCs against WA1 (P = .009) and Omicron (P = .02). The geometric mean and surrogate neutralization titer above the limit of detection was 346.0 for WA1 and 39.7 for Omicron, an 8.7-fold decrease (P < .001). After adjustment of covariates in the WA1-specific model, we observed a 47% reduction in the odds of postvaccination infection for every standard deviation increase in RBD AUC (aOR, 0.53 [95% confidence interval, .29-.97) and a 69% reduction in the odds of infection for every 3-fold increase in RBD end titer (0.31 [.06-1.57]). CONCLUSIONS: Children with higher antibody levels experienced a lower incidence of postvaccination SARS-CoV-2 infection.

Strategies to prevent catheter-associated urinary tract infections (CAUTIs) | Essential practices | Infrastructure and resources | 1 Perform a CAUTI risk assessment and implement an organization-wide program to identify and remove catheters that are no longer necessary using 1 or | more methods documented to be effective. (Quality of evidence: MODERATE) | 2 Provide appropriate infrastructure for preventing CAUTI. (Quality of evidence: LOW) | 3 Provide and implement evidence-based protocols to address multiple steps of the urinary catheter life cycle: catheter appropriateness (step 0), insertion | technique (step 1), maintenance care (step 2), and prompt removal (step 3) when no longer appropriate. (Quality of evidence: LOW) | 4 Ensure that only trained healthcare personnel (HCP) insert urinary catheters and that competency is assessed regularly. (Quality of evidence: LOW) | 5 Ensure that supplies necessary for aseptic technique for catheter insertion are available and conveniently located. (Quality of evidence: LOW) | 6 Implement a system for documenting the following in the patient record: physician order for catheter placement, indications for catheter insertion, date | and time of catheter insertion, name of individual who inserted catheter, nursing documentation of placement, daily presence of a catheter and | maintenance care tasks, and date and time of catheter removal. Record criteria for removal and justification for continued use. (Quality of evidence: | LOW) | 7 Ensure that sufficiently trained HCP and technology resources are available to support surveillance for catheter use and outcomes. (Quality of evidence: | LOW) | 8 Perform surveillance for CAUTI if indicated based on facility risk assessment or regulatory requirements. (Quality of evidence: LOW) | 9 Standardize urine culturing by adapting an institutional protocol for appropriate indications for urine cultures in patients with and without indwelling | catheters. Consider incorporating these indications into the electronic medical record, and review indications for ordering urine cultures in the CAUTI | risk assessment. (Quality of evidence: LOW) | Education and training | 1 Educate HCP involved in the insertion, care, and maintenance of urinary catheters about CAUTI prevention, including alternatives to indwelling | catheters, and procedures for catheter insertion, management, and removal. (Quality of evidence: LOW) | 2 Assess healthcare professional competency in catheter use, catheter care, and maintenance. (Quality of evidence: LOW) | 3 Educate HCP about the importance of urine-culture stewardship and provide indications for urine cultures. (Quality of evidence: LOW) | 4 Provide training on appropriate collection of urine. Specimens should be collected and should arrive at the microbiology laboratory as soon as possible, | preferably within an hour. If delay in transport to the laboratory is expected, samples should be refrigerated (no more than 24 hours) or collected in | preservative urine transport tubes. (Quality of evidence: LOW) | 5 Train clinicians to consider other methods for bladder management, such as intermittent catheterization or external male or female collection devices, | when appropriate, before placing an indwelling urethral catheter. (Quality of evidence: LOW) | 6 Share data in a timely fashion and report to appropriate stakeholders. (Quality of evidence: LOW) | Insertion of indwelling catheters | 1 Insert urinary catheters only when necessary for patient care and leave in place only as long as indications remain. (Quality of evidence: MODERATE) | 2 Consider other methods for bladder management such as intermittent catheterization, or external male or female collection devices, when appropriate. | (Quality of evidence: LOW) | 3 Use appropriate technique for catheter insertion. (Quality of evidence: MODERATE). | 4 Consider working in pairs to help perform patient positioning and monitor for potential contamination during placement. (Quality of evidence: LOW) | 5 Practice hand hygiene (based on CDC or WHO guidelines) immediately before insertion of the catheter and before and after any manipulation of the | catheter site or apparatus. (Quality of evidence: LOW) | 6 Insert catheters following aseptic technique and using sterile equipment. (Quality of evidence: LOW) | 7 Use sterile gloves, drape, and sponges, a sterile antiseptic solution for cleaning the urethral meatus, and a sterile single-use packet of lubricant jelly for | insertion. (Quality of evidence: LOW) | 8 Use a catheter with the smallest feasible diameter consistent with proper drainage to minimize urethral trauma but consider other catheter types and | sizes when warranted for patients with anticipated difficult catheterization to reduce the likelihood that a patient will experience multiple, sometimes | traumatic, catheterization attempts. (Quality of evidence: LOW) | Management of indwelling catheters | 1 Properly secure indwelling catheters after insertion to prevent movement and urethral traction. (Quality of evidence: LOW) | 2 Maintain a sterile, continuously closed drainage system. (Quality of evidence: LOW) | 3 Replace the catheter and the collecting system using aseptic technique when breaks in aseptic technique, disconnection, or leakage occur. (Quality of | evidence: LOW) | 4 For examination of fresh urine, collect a small sample by aspirating urine from the needleless sampling port with a sterile syringe/cannula adaptor after | cleansing the port with disinfectant. (Quality of evidence: LOW) | (Continued) | 2 Deborah S. Yokoe et al | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Strategies to prevent central-line–associated bloodstream infections (CLABSIs) | (Continued ) | 5 Facilitate timely transport of urine samples to laboratory. If timely transport is not feasible, consider refrigerating urine samples or using samplecollection cups with preservatives. Obtain larger volumes of urine for special analyses (eg, 24-hour urine) aseptically from the drainage bag. (Quality of | evidence: LOW) | 6 Maintain unobstructed urine flow. (Quality of evidence: LOW) | 7 Employ routine hygiene. Cleaning the meatal area with antiseptic solutions is an unresolved issue, though emerging literature supports chlorhexidine | use prior to catheter insertion. Alcohol-based products should be avoided given concerns about the alcohol causing drying of the mucosal tissues. | (Quality of evidence: LOW) | Additional approaches | 1 Develop a protocol for standardizing diagnosis and management of postoperative urinary retention, including nurse-directed use of intermittent | catheterization and use of bladder scanners when appropriate as alternatives to indwelling urethral catheterization. (Quality of evidence: MODERATE) | 2 Establish a system for analyzing and reporting data on catheter use and adverse events from catheter use. (Quality of evidence: LOW) | 3 Establish a system for defining, analyzing, and reporting data on non–catheter-associated UTIs, particularly UTIs associated with the use of devices | being used as alternatives to indwelling urethral catheters. (Quality of evidence: LOW) | Essential practices | Before insertion | 1 Provide easy access to an evidence-based list of indications for CVC use to minimize unnecessary CVC placement. (Quality of evidence: LOW) | 2 Require education and competency assessment of healthcare personnel (HCP) involved in insertion, care and maintenance of CVCs about CLABSI | prevention. (Quality of evidence: MODERATE) | 3 Bathe ICU patients aged >2 months with a chlorhexidine preparation on a daily basis. (Quality of evidence: HIGH) | At insertion | 1 In ICU and non-ICU settings, a facility should have a process in place, such as a checklist, to ensure adherence to infection prevention practices at the | time of CVC insertion. (Quality of evidence: MODERATE) | 2 Perform hand hygiene prior to catheter insertion or manipulation. (Quality of evidence: MODERATE) | 3 The subclavian site is preferred to reduce infectious complications when the catheter is placed in the ICU setting. (Quality of evidence: HIGH) | 4 Use an all-inclusive catheter cart or kit. (Quality of evidence: MODERATE) | 5 Use ultrasound guidance for catheter insertion. (Quality of evidence: HIGH) | 6 Use maximum sterile barrier precautions during CVC insertion. (Quality of evidence: MODERATE) | After insertion | 1 Ensure appropriate nurse-to-patient ratio and limit use of float nurses in ICUs. (Quality of evidence: HIGH) | 2 Use chlorhexidine-containing dressings for CVCs in patients aged >2 months. (Quality of evidence: HIGH) | 3 For nontunneled CVCs in adults and children, change transparent dressings and perform site care with a chlorhexidine-based antiseptic at least every 7 | days or immediately if the dressing is soiled, loose, or damp. Change gauze dressings every 2 days or earlier if the dressing is soiled, loose, or damp. | (Quality of evidence: MODERATE) | 4 Disinfect catheter hubs, needleless connectors, and injection ports before accessing the catheter. (Quality of evidence: MODERATE) | 5 Remove nonessential catheters. (Quality of evidence: MODERATE) | 6 Routine replacement of administration sets not used for blood, blood products, or lipid formulations can be performed at intervals up to 7 days. | (Quality of evidence: HIGH) | 7 Perform surveillance for CLABSI in ICU and non-ICU settings. (Quality of evidence: HIGH) | Additional approaches | 1 Use antiseptic or antimicrobial-impregnated CVCs. (Quality of evidence: HIGH in adult patients; MODERATE in pediatric patients) | 2 Use antimicrobial lock therapy for long-term CVCs. (Quality of evidence: HIGH) | 3 Use recombinant tissue plasminogen activating factor (rt-PA) once weekly after hemodialysis in patients undergoing hemodialysis through a CVC. | (Quality of evidence: HIGH) | 4 Utilize infusion or vascular access teams for reducing CLABSI rates. (Quality of evidence: LOW) | 5 Use antimicrobial ointments for hemodialysis catheter-insertion sites. (Quality of evidence: HIGH) | 6 Use an antiseptic-containing hub, connector cap, or port protector to cover connectors. (Quality of evidence: MODERATE) | Infection Control & Hospital Epidemiology 3 | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Strategies to prevent Clostridioides difficile infections (CDIs) | Strategies to prevent methicillin-resistant Staphylococcus aureus (MRSA) transmission and infection | Essential practices | 1 Encourage appropriate use of antimicrobials through implementation of an antimicrobial stewardship program. (Quality of evidence: MODERATE) | 2 Implement diagnostic stewardship practices for ensuring appropriate use and interpretation of C. difficile testing. (Quality of evidence: LOW) | 3 Use contact precautions for infected patients, single-patient room preferred. (Quality of evidence: LOW for hand hygiene; MODERATE for gloves; LOW | for gowns; LOW for single-patient room) | 4 Adequately clean and disinfect equipment and the environment of patients with CDI. (Quality of evidence: LOW for equipment; LOW for environment) | 5 Assess the adequacy of room cleaning. (Quality of evidence: LOW) | 6 Implement a laboratory-based alert system to provide immediate notification to infection preventionists and clinical personnel about newly diagnosed | patients with CDI. (Quality of evidence: LOW) | 7 Conduct CDI surveillance and analyze and report CDI data. (Quality of evidence: LOW) | 8 Educate healthcare personnel (HCP), environmental service personnel, and hospital administration about CDI. (Quality of evidence: LOW) | 9 Educate patients and their families about CDI as appropriate. (Quality of evidence: LOW) | 10 Measure compliance with CDC or WHO hand hygiene and contact precaution recommendations. (Quality of evidence: LOW) | Additional approaches | 1 Intensify the assessment of compliance with process measures. (Quality of evidence: LOW) | 2 Perform hand hygiene with soap and water as the preferred method following care of or interacting with the healthcare environment of a patient with | CDI. (Quality of evidence: LOW) | 3 Place patients with diarrhea on contact precautions while C. difficile testing is pending. (Quality of evidence: LOW) | 4 Prolong the duration of contact precautions after the patient becomes asymptomatic until hospital discharge. (Quality of evidence: LOW) | 5 Use an EPA-approved sporicidal disinfectant, such as diluted (1:10) sodium hypochlorite, for environmental cleaning and disinfection. Implement a | system to coordinate with environmental services if it is determined that sodium hypochlorite is needed for environmental disinfection. (Quality of | evidence: LOW) | Essential practices | 1 Implement an MRSA monitoring program. (Quality of evidence: LOW) | 2 Conduct an MRSA risk assessment. (Quality of evidence: LOW) | 3 Promote compliance with CDC or World Health Organization (WHO) hand hygiene recommendations. (Quality of evidence: MODERATE) | 4 Use contact precautions for MRSA-colonized and MRSA-infected patients. A facility that chooses or has already chosen to modify the use of contact | precautions for some or all of these patients should conduct an MRSA-specific risk assessment to evaluate the facility for transmission risks and to | assess the effectiveness of other MRSA risk mitigation strategies (eg, hand hygiene, cleaning and disinfection of the environment, single occupancy | patient rooms) and should establish a process for ongoing monitoring, oversight, and risk assessment. (Quality of evidence: MODERATE) | 5 Ensure cleaning and disinfection of equipment and the environment. (Quality of evidence: MODERATE) | 6 Implement a laboratory-based alert system that notifies healthcare personnel (HCP) of new MRSA-colonized or MRSA-infected patients in a timely | manner. (Quality of evidence: LOW) | 7 Implement an alert system that identifies readmitted or transferred MRSA-colonized or MRSA-infected patients. (Quality of evidence: LOW) | 8 Provide MRSA data and outcome measures to key stakeholders, including senior leadership, physicians, nursing staff, and others. (Quality of evidence: | LOW) | 9 Educate healthcare personnel about MRSA. (Quality of evidence: LOW) | 10 Educate patients and families about MRSA. (Quality of evidence: LOW) | 11 Implement an antimicrobial stewardship program. (Quality of evidence: LOW) | Additional approaches | Active surveillance testing (AST) | 1 Implement an MRSA AST program for select patient populations as part of a multifaceted strategy to control and prevent MRSA. (Quality of evidence: | MODERATE) Note: specific populations may have different evidence ratings. | 2 Active surveillance for MRSA in conjunction with decolonization can be performed in targeted populations prior to surgery to prevent postsurgical | MRSA infection. (Quality of evidence: MODERATE) | (Continued) | 4 Deborah S. Yokoe et al | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Strategies to prevent surgical-site infections (SSIs) | (Continued ) | 3 Active surveillance with contact precautions is inferior to universal decolonization for reduction of MRSA clinical isolates in adult ICUs. (Quality of | evidence: HIGH) | 4 Hospital-wide active surveillance for MRSA can be used in conjunction with contact precautions to reduce the incidence of MRSA infection. (Quality of | evidence: MODERATE) | 5 Active surveillance can be performed in the setting of an MRSA outbreak or evidence of ongoing transmission of MRSA within a unit as part of a | multifaceted strategy to halt transmission. (Quality of evidence: MODERATE) | Screen healthcare personnel for MRSA infection or colonization | 1 Screen HCP for MRSA infection or colonization if they are epidemiologically linked to a cluster of MRSA infections. (Quality of evidence: LOW) | MRSA decolonization therapy | 1 Use universal decolonization (ie, daily CHG bathing plus 5 days of nasal decolonization) for all patients in adult ICUs to reduce endemic MRSA clinical | cultures. (Quality of evidence: HIGH) | 2 Perform preoperative nares screening with targeted use of CHG and nasal decolonization in MRSA carriers to reduce MRSA SSI from surgical | procedures involving implantation of hardware. (Quality of evidence: MODERATE) | 3 Screen for MRSA and provide targeted decolonization with CHG bathing and nasal decolonization to MRSA carriers in surgical units to reduce | postoperative MRSA inpatient infections. (Quality of evidence: MODERATE) | 4 Provide CHG bathing plus nasal decolonization to known MRSA carriers outside the ICU with medical devices, specifically central lines, midline | catheters, and lumbar drains to reduce MRSA clinical cultures. (Quality of evidence: MODERATE) | 5 Consider postdischarge decolonization of MRSA carriers to reduce postdischarge MRSA infections and readmissions. (Quality of evidence: HIGH) | 6 Neonatal ICUs should consider targeted or universal decolonization during times of above-average MRSA infection rates or targeted decolonization for | patients at high risk of MRSA infection (eg, low birth weight, indwelling devices, or prior to high-risk surgeries). (Quality of evidence: MODERATE) | 7 Burn units should consider targeted or universal decolonization during times of above-average MRSA infection rates. (Quality of evidence: MODERATE) | 8 Consider targeted or universal decolonization of hemodialysis patients. (Quality of evidence: MODERATE) | 9 Decolonization should be strongly considered as part of a multimodal approach to control MRSA outbreaks. (Quality of evidence: MODERATE) | Universal use of gowns and gloves | 1 Use gowns and gloves when providing care to or entering the room of any adult ICU patient, regardless of MRSA colonization status. (Quality of | evidence: MODERATE) | Essential practices | 1 Administer antimicrobial prophylaxis according to evidence-based standards and guidelines. (Quality of evidence: HIGH) | 2 Use a combination of parenteral and oral antimicrobial prophylaxis prior to elective colorectal surgery to reduce the risk of SSI. (Quality of evidence: | HIGH) | 3 Decolonize surgical patients with an anti-staphylococcal agent in the preoperative setting for orthopedic and cardiothoracic procedures. (Quality of | evidence: HIGH) | Decolonize surgical patients in other procedures at high risk of staphylococcal SSI, such as those involving prosthetic material. (Quality of evidence: | LOW) | 4 Use antiseptic-containing preoperative vaginal preparation agents for patients undergoing cesarean delivery or hysterectomy. (Quality of evidence: | MODERATE) | 5 Do not remove hair at the operative site unless the presence of hair will interfere with the surgical procedure. (Quality of evidence: MODERATE) | 6 Use alcohol-containing preoperative skin preparatory agents in combination with an antiseptic. (Quality of evidence: HIGH) | 7 For procedures not requiring hypothermia, maintain normothermia (temperature >35.5 °C) during the perioperative period. (Quality of evidence: HIGH). | 8 Use impervious plastic wound protectors for gastrointestinal and biliary tract surgery. (Quality of evidence: HIGH) | 9 Perform intraoperative antiseptic wound lavage. (Quality of evidence: MODERATE) | 10 Control blood glucose level during the immediate postoperative period for all patients. (Quality of evidence: HIGH) | 11 Use a checklist and/or bundle to ensure compliance with best practices to improve surgical patient safety. (Quality of evidence: HIGH) | 12 Perform surveillance for SSI. (Quality of evidence: MODERATE) | 13 Increase the efficiency of surveillance by utilizing automated data. (Quality of evidence: MODERATE) | 14 Provide ongoing SSI rate feedback to surgical and perioperative personnel and leadership. (Quality of evidence: MODERATE) | 15 Measure and provide feedback to healthcare personnel (HCP) regarding rates of compliance with process measures. (Quality of evidence: LOW) | (Continued) | Infection Control & Hospital Epidemiology 5 | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Strategies to prevent ventilator-associated pneumonia (VAP) and ventilator-associated events (VAEs) | Adult patients | (Continued ) | 16 Educate surgeons and perioperative personnel about SSI prevention measures. (Quality of evidence: LOW) | 17 Educate patients and their families about SSI prevention as appropriate. (Quality of evidence: LOW) | 18 Implement policies and practices to reduce the risk of SSI for patients that align with applicable evidence-based standards, rules and regulations, and | medical device manufacturer instructions for use. (Quality of evidence: MODERATE) | 19 Observe and review operating room personnel and the environment of care in the operating room and in central sterile reprocessing. (Quality of | evidence: LOW) | Additional approaches | 1 Perform an SSI risk assessment. (Quality of evidence: LOW) | 2 Consider use of negative-pressure dressings in patients who may benefit. (Quality of evidence: MODERATE) | 3 Observe and review practices in the preoperative clinic, post-anesthesia care unit, surgical intensive care unit, and/or surgical ward. (Quality of | evidence: MODERATE) | 4 Use antiseptic-impregnated sutures as a strategy to prevent SSI. (Quality of evidence: MODERATE) | Essential practices | Interventions with little risk of harm and that are associated with decreases in duration of mechanical ventilation, length of stay, mortality, antibiotic utilization, | and/or costs | Avoid intubation and prevent reintubation if possible. | 1 Use high flow nasal oxygen or non-invasive positive pressure ventilation (NIPPV) as appropriate, whenever safe and feasible. (Quality of evidence: HIGH) | Minimize sedation. | 1 Minimize sedation of ventilated patients whenever possible. (Quality of evidence: HIGH) | 2 Preferentially use multimodal strategies and medications other than benzodiazepines to manage agitation. (Quality of evidence: HIGH) | 3 Utilize a protocol to minimize sedation. (Quality of evidence: HIGH) | 4 Implement a ventilator liberation protocol. (Quality of evidence: HIGH) | Maintain and improve physical conditioning. | 1 Provide early exercise and mobilization. (Quality of evidence: MODERATE) | Elevate the head of the bed to 30°–45°. (Quality of evidence: LOW) | Provide oral care with toothbrushing but without chlorhexidine. (Quality of evidence: MODERATE) | Provide early enteral rather than parenteral nutrition. (Quality of evidence: HIGH) | Maintain ventilator circuits. | 1 Change the ventilator circuit only if visibly soiled or malfunctioning (or per manufacturers’ instructions) (Quality of evidence: HIGH). | Additional approaches | May decrease duration of mechanical ventilation, length of stay, and/or mortality in some populations but not in others, and they may confer some risk of harm | in some populations. | 1 Consider using selective decontamination of the oropharynx and digestive tract to decrease microbial burden in ICUs with low prevalence of antibiotic | resistant organisms. Antimicrobial decontamination is not recommended in countries, regions, or ICUs with high prevalence of antibiotic-resistant | organisms. (Quality of evidence: HIGH) | Additional approaches | May lower VAP rates, but current data are insufficient to determine their impact on duration of mechanical ventilation, length of stay, and mortality. | 1 Consider using endotracheal tubes with subglottic secretion drainage ports to minimize pooling of secretions above the endotracheal cuff in patients | likely to require >48–72 hours of intubation. (Quality of evidence: MODERATE) | 2 Consider early tracheostomy. (Quality of evidence: MODERATE) | 3 Consider postpyloric feeding tube placement in patients with gastric feeding intolerance at high risk for aspiration. (Quality of evidence: MODERATE) | 6 Deborah S. Yokoe et al | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Preterm neonatal patients | Pediatric patients | Essential practices | Confer minimal risk of harm and may lower VAP and/or PedVAE rates. | Avoid intubation. (Quality of evidence: HIGH) | Minimize duration of mechanical ventilation. (Quality of evidence: HIGH) | 1 Manage patients without sedation whenever possible. (Quality of evidence: LOW) | 2 Use caffeine therapy for apnea of prematurity within 72 hours after birth to facilitate extubation. (Quality of evidence: HIGH) | 3 Assess readiness to extubate daily. (Quality of evidence: LOW) | 4 Take steps to minimize unplanned extubation and reintubation. (Quality of evidence: LOW) | 5 Provide regular oral care with sterile water (extrapolated from practice in infants and children, no data in preterm neonates). (Quality of evidence: | LOW) | 6 Change the ventilator circuit only if visibly soiled or malfunctioning or according to the manufacturer’s instructions for use (extrapolated from studies in | adults and children, no data in preterm neonates). (Quality of evidence: LOW) | Additional approaches | Minimal risks of harm, but impact on VAP and VAE rates is unknown. | 1 Lateral recumbent positioning. (Quality of evidence: LOW) | 2 Reverse Trendelenberg positioning. (Quality of evidence: LOW) | 3 Closed or in-line suctioning. (Quality of evidence: LOW) | 4 Oral care with maternal colostrum. (Quality of evidence: MODERATE) | Essential practices | Confer minimal risk of harm and some data suggest that they may lower VAP rates, PedVAE rates, and/or duration of mechanical ventilation. | Avoid intubation. | 1 Use noninvasive positive pressure ventilation (NIPPV) or high-flow oxygen by nasal cannula whenever safe and feasible. (Quality of evidence: | MODERATE) | Minimize duration of mechanical ventilation. | 1 Assess readiness to extubate daily using spontaneous breathing trials in patients without contraindications. (Quality of evidence: MODERATE) | 2 Take steps to minimize unplanned extubations and reintubations. (Quality of evidence: LOW) | 3 Avoid fluid overload. (Quality of evidence: MODERATE) | Provide regular oral care (ie, toothbrushing or gauze if no teeth). (Quality of evidence: LOW) | Elevate the head of the bed unless medically contraindicated. (Quality of evidence: LOW) | Maintain ventilator circuits. | 1 Change ventilator circuits only when visibly soiled or malfunctioning (or per manufacturer’s instructions). (Quality of evidence: MODERATE) | 2 Remove condensate from the ventilator circuit frequently and avoid draining the condensate toward the patient. (Quality of evidence: LOW) | Endotracheal tube selection and management | 1 Use cuffed endotracheal tubes. (Quality of evidence: LOW) | 2 Maintain cuff pressure and volume at the minimal occlusive settings to prevent clinically significant air leaks around the endotracheal tube, typically | 20-25cm H2O. This “minimal leak” approach is associated with lower rates of post-extubation stridor. (Quality of evidence: LOW) | 3 Suction oral secretions before each position change. (Quality of evidence: LOW) | Additional approaches | Minimal risks of harm and some evidence of benefit in adult patients but data in pediatric populations are limited. | 1 Minimize sedation. (Quality of evidence: MODERATE) | 2 Use endotracheal tubes with subglottic secretion drainage ports for patients ≥10 years of age. (Quality of evidence: LOW) | 3 Consider early tracheostomy. (Quality of evidence: LOW) | Infection Control & Hospital Epidemiology 7 | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Strategies to prevent nonventilator hospital-acquired pneumonia (NV-HAP) | Strategies to prevent healthcare-associated infections through hand hygiene | Essential practices | Promote the maintenance of healthy hand skin and nails. (Quality of evidence: HIGH) | 1 Promote the preferential use of alcohol-based hand sanitizer (ABHS) in most clinical situations. (Quality of evidence: HIGH) | 2 Perform hand hygiene as indicated by CDC or the WHO Five Moments. (Quality of evidence: HIGH) | 3 Include fingernail care in facility-specific policies related to hand hygiene. (Quality of evidence: HIGH) | a) Healthcare personnel (HCP) should maintain short, natural fingernails. | b) Nails should not extend past the fingertip. | c) HCP who provide direct or indirect care in high-risk areas | (eg, ICU or perioperative) should not wear artificial fingernail extenders. | d) Prohibitions against fingernail polish (standard or gel shellac) are at the discretion of the infection prevention program, except among scrubbed | individuals who interact with the sterile field during surgical procedures; these individuals should not wear fingernail polish or gel shellac. | 4 Engage all HCP in primary prevention of occupational irritant and allergic contact dermatitis. (Quality of evidence: HIGH) | 5 Provide cotton glove liners for HCP with hand irritation and educate these HCP on their use. (Quality of evidence: MODERATE) | Select appropriate products. | 1 For routine hand hygiene, choose liquid, gel, or foam ABHS with at least 60% alcohol. (Quality of evidence: HIGH) | 2 Involve HCP in selection of products. (Quality of evidence: HIGH) | 3 Obtain and consider manufacturers’ product-specific data if seeking ABHS with ingredients that may enhance efficacy against organisms anticipated to | be less susceptible to biocides. (Quality of evidence: MODERATE) | 4 Confirm that the volume of ABHS dispensed is consistent with the volume shown to be efficacious. (Quality of evidence: HIGH) | 5 Educate HCP about an appropriate volume of ABHS and the time required to obtain effectiveness. (Quality of evidence: HIGH) | 6 Provide facility-approved hand moisturizer that is compatible with antiseptics and gloves. (Quality of evidence: HIGH) | 7 For surgical antisepsis, use an FDA-approved surgical hand scrub or waterless surgical hand rub. (Quality of evidence: HIGH) | Ensure the accessibility of hand hygiene supplies. (Quality of evidence: HIGH) | 1 Ensure ABHS dispensers are unambiguous, visible, and accessible within the workflow of HCP. (Quality of evidence: HIGH) | 2 In private rooms, consider 2 ABHS dispensers the minimum threshold for adequate numbers of dispensers: 1 dispenser in the hallway, and 1 in the | patient room. (Quality of evidence: HIGH) | 3 In semiprivate rooms, suites, bays, and other multipatient bed configurations, consider 1 dispenser per 2 beds the minimum threshold for adequate | numbers of dispensers. Place ABHS dispensers in the workflow of HCP. (Quality of evidence: LOW) | 4 Ensure that the placement of hand hygiene supplies (eg, individual pocket-sized dispensers, bed mounted ABHS dispenser, single use pump bottles) is | easily accessible for HCP in all areas where patients receive care. (Quality of evidence: HIGH) | 5 Evaluate for the risk of intentional consumption. Utilize dispensers that mitigate this risk, such as wall-mounted dispensers that allow limited numbers | of activations within short periods (eg, 5 seconds). (Quality of evidence: LOW) | 6 Have surgical hand rub and scrub available in perioperative areas. (Quality of evidence: HIGH) | 7 Consider providing ABHS hand rubs or handwash with FDA-approved antiseptics for use in procedural areas and prior to high-risk bedside procedures | (eg, central-line insertion). (Quality of evidence: LOW) | (Continued) | Practices supported by interventional studies suggesting lower | NV-HAP rates | 1 Provide regular oral care. | 2 Diagnose and manage dysphagia. | 3 Provide early mobilization. | 4 Implement multimodal interventions to prevent viral infections. | 5 Use prevention bundles. | 8 Deborah S. Yokoe et al | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Implementing strategies to prevent healthcare-associated infections | Standard approach to implementation | Examples of implementation frameworks | (Continued ) | Ensure appropriate glove use to reduce hand and environmental contamination. (Quality of Evidence: HIGH) | 1 Use gloves for all contact with the patient and environment as indicated by standard and contact precautions during the care of individuals with | organisms confirmed to be less susceptible to biocides (e.g., C. difficile or norovirus) | 2 Educate HCP about the potential for self-contamination and environmental contamination when gloves are worn. (Quality of evidence: HIGH) | 3 Educate and confirm the ability of HCP to doff gloves in a manner that avoids contamination. (Quality of evidence: HIGH) | Take steps to reduce environmental contamination associated with sinks and sink drains. (Quality of evidence: HIGH) | Monitor adherence to hand hygiene. (Quality of evidence: HIGH) | Provide timely and meaningful feedback to enhance a culture of safety. (Quality of evidence: MODERATE) | Additional approaches during outbreaks | 1 Consider educating HCP using a structured approach (eg, WHO Steps) for handwashing or hand sanitizing. Evaluate HCP adherence to technique. | (Quality of evidence: LOW) | 2 For waterborne pathogens of premise plumbing, consider disinfection of sink drains using an EPA-registered disinfectant with claims against biofilms. | Consult with state or local public health for assistance in determining appropriate protocols for use and other actions needed to ensure safe supply. | (Quality of evidence: LOW) | 3 For C. difficile and norovirus, in addition to contact precautions, encourage hand washing with soap and water after the care of patients with known or | suspected infections. (Quality of evidence: LOW) | 1 Assess determinants of change and | classify as follows: | • Facilitators: promote practice or | change, or | • Barriers: hinder practice or change | Individual level: healthcare personnel, leaders, patients, and visitors’ preferences, needs, attitudes, and | knowledge. | Facility level: team composition, communication, culture, capacity, policies, resources. | Partners: degree of support and buy-in. | 2 Choose measures Measurement methods must be appropriate for the question(s) they seek to answer and adhere to the | methods’ data collection and analysis rules: | • Outcome measure: ultimate goal (eg, HAI reduction). | • Process measure: action reliability (eg, bundle adherence). | • Balancing measure: undesired outcome of change (eg, staff absences due to required vaccine side effects). | 3 Select framework(s) See below and “Implementing Strategies to Prevent Infections in Acute Care Settings” (Table 3) | 32 | Framework Published Experience Resources | 4Es Settings | • Healthcare facilities | • Large-scale projects including multiple | sites | Infection prevention and control | • HAI prevention (including mortality | reduction and cost savings) | • 4Es Framework11 | • HAI reduction12–14 | • Mortality reduction15 | • Cost savings16 | Behavior Change Wheel Settings | • Community-based practice | • Healthcare facilities | Healthy behaviors | • Smoking cessation | • Obesity prevention | • Increased physical activity | Infection prevention and control | • Hand hygiene adherence | • Antibiotic prescribing17 | • Behavior Change Wheel: A Guide to Designing Interventions18 | • Stand More at Work (SMArT Work)19 | (Continued) | Infection Control & Hospital Epidemiology 9 | https://doi.org/10.1017/ice.2023.138 Published online by Cambridge University Press | Acknowledgments. The Compendium Partners thank the authors for their | dedication to this work, including maintaining adherence to the rigorous | process for the development of the Compendium: 2022 Updates, involving but | not limited to screening of thousands of articles; achieving multilevel consensus; | and consideration of, response to, and incorporation of many organizations’ | feedback and comments. We acknowledge these efforts especially because they | occurred as the authors handled the demands of the COVID-19 pandemic. The | authors thank Valerie Deloney, MBA, for her organizational expertise in the | development of this manuscript and Janet Waters, MLS, BSN, RN, for her | expertise in developing the strategies used for the literature searches that | informed this manuscript. The authors thank the many individuals and | organizations who gave their time and expertise to review and provide | (Continued ) | Comprehensive Unit-based | Safety Program (CUSP) | Settings | • Intensive care units | • Ambulatory centers | Improvements | • Antibiotic prescribing | • CLABSI prevention | • CAUTI prevention | • CUSP Implementation Toolkit20 | • AHA/HRET: Eliminating CAUTI (Stop CAUTI)21 | • AHRQ Toolkit to Improve Safety in Ambulatory Surgery Centers22 | European Mixed Methods Settings | • European institutions of varied | healthcare systems and cultures | Improvements: | • CLABSI prevention | • Hand hygiene | • PROHIBIT: Description and Materials23 | Getting to Outcomes (GTO)® Settings | • Community programs and services | Improvements | • Sexual health promotion | • Dual-disorder treatment program in | veterans | • Community emergency preparedness | • RAND Guide for Emergency Preparedness24 (illustrated overview of GTO® methodology) | Model for Improvement Settings | • Healthcare (inpatient, perioperative, | ambulatory) | • Public health | Interventions | • PPE use | • HAI prevention | • Public health process evaluation | • Institute for Healthcare Improvement25 | • The Improvement Guide26 | • Deming’s System of Profound Knowledge27 | Reach, Effectiveness, Adoption, | Implementation, Maintenance | (RE-AIM) | Settings | • Healthcare | • Public health | • Community programs | • Sexual health | Evaluations | • Antimicrobial stewardship in the ICU | • Clinical practice guidelines for STIs | • Promotion of vaccination | • Implementation of contact tracing | • RE-AIM.org28 | • Understanding and applying the RE-AIM framework: Clarifications and | resources29 | Replicating Effective Practices | (REP) | Settings | • Healthcare | • Public health | • HIV prevention | Interventions that have produced | positive results are reframed for local | relevance | CDC Compendium of HIV Prevention Interventions with Evidence of | Effectiveness30 (see Section C, Intervention Checklist) | Theoretical Domains Settings | • Healthcare (inpatient, perioperative, | ambulatory) | • Community (individual and communitybased behaviors) | Health maintenance | • Diabetes management in primary care | • Pregnancy weight management | HCP practice | • ICU blood transfusion | • Selective GI tract decontamination | • Preoperative testing | • Spine imaging | • Hand hygiene

BACKGROUND Information is limited on messenger RNA (mRNA) BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) COVID-19 vaccine effectiveness (VE) in preventing SARS-CoV-2 infection or attenuating disease when administered in real-world conditions.METHODS Prospective cohorts of 3,975 healthcare personnel, first responders, and other essential and frontline workers completed weekly SARS-CoV-2 testing during December 14 2020—April 10 2021. Self-collected mid-turbinate nasal swabs were tested by qualitative and quantitative reverse-transcription–polymerase-chain-reaction (RT-PCR). VE was calculated as 100%×(1−hazard ratio); adjusted VE was calculated using vaccination propensity weights and adjustments for site, occupation, and local virus circulation.RESULTS SARS-CoV-2 was detected in 204 (5.1%) participants; 16 were partially (≥14 days post-dose-1 to 13 days after dose-2) or fully (≥14 days post-dose-2) vaccinated, and 156 were unvaccinated; 32 with indeterminate status (&lt;14 days after dose-1) were excluded. Adjusted mRNA VE of full vaccination was 91% (95% confidence interval [CI]=76%–97%) against symptomatic or asymptomatic SARS-CoV-2 infection; VE of partial vaccination was 81% (95% CI=64%-90%). Among partially or fully vaccinated participants with SARS-CoV-2 infection, mean viral RNA load (Log10 copies/mL) was 40% lower (95% CI=16%-57%), the risk of self-reported febrile COVID-19 was 58% lower (Risk Ratio=0.42, 95% CI=0.18-0.98), and 2.3 fewer days (95% CI=0.8-3.7) were spent sick in bed compared to unvaccinated infected participants.CONCLUSIONS Authorized mRNA vaccines were highly effective among working-age adults in preventing SARS-CoV-2 infections when administered in real-world conditions and attenuated viral RNA load, febrile symptoms, and illness duration among those with breakthrough infection despite vaccination.Competing Interest StatementAllison L. Naleway reported funding from Pfizer for a meningococcal B vaccine study unrelated to the submitted work. Kurt T. Hegmann serves at the Editor of the American College of Occupational and Environmental Medicine evidence-based practice guidelines. Matthew S. These reported grants and personal fees from Reed Group and the American College of Occupational and Environmental Medicine, outside the submitted work. Other authors have reported no conflicts of interest.Funding StatementFunding provided in whole or in part by federal funds from the National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention under contract numbers 75D30120R68013 awarded to Marshfield Clinic Research Laboratory, 75D30120C08379 to University of Arizona, and 75D30120C08150 awarded to Abt Associates, Inc.Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:This study was reviewed and approved by the University of Arizona IRB as the single IRB for this studyAll necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesSummary data will be available once all study objectives are met.

Law Enforcement Officers (LEOs), firefighters, and other first responders are at increased risk of SARS-CoV-2 infection compared to healthcare personnel but have relatively low COVID-19 vaccine uptake. Resistance to COVID-19 vaccine mandates among first responders has the potential to disrupt essential public services and threaten public health and safety. Using data from the HEROES-RECOVER prospective cohorts, we report on the increased illness burden of COVID-19 among unvaccinated first responders. From January to September 2021, first responders contributed to weekly active surveillance for COVID-19-like illness (CLI). Self-collected respiratory specimens collected weekly, irrespective of symptoms, and at the onset CLI were tested by Reverse Transcription Polymerase Chain Reaction (RT-PCR) assay for SARSCoV-2. Among 1415 first responders, 17% were LEOs, 68% firefighters, and 15% had other first responder occupations. Unvaccinated (41%) compared to fully vaccinated (59%) first responders were less likely to believe COVID-19 vaccines are very or extremely effective (17% versus 54%) or very or extremely safe (15% versus 54%). From January through September 2021, among unvaccinated LEOs, the incidence of COVID-19 was 11.9 per 1,000 person-weeks (95%CI=7.0-20.1) compared to only 0.6 (95%CI=0.2-2.5) among vaccinated LEOs. Incidence of COVID-19 was also higher among unvaccinated firefighters (9.0 per 1,000 person-weeks; 95%CI=6.4-12.7) compared to those vaccinated (1.8 per 1,000; 95%CI=1.1-2.8). Once they had laboratory-confirmed COVID-19, unvaccinated first responders were sick for a mean+/-SD of 14.7+/-21.7 days and missed a mean of 38.0+/-46.0 hours of work. These findings suggest that state and local governments with large numbers of unvaccinated first responders may face major disruptions in their workforce due to COVID-19 illness. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license.

Background: The natural history of SARS-CoV-2 infection and transmission dynamics may have changed as SARS-CoV-2 has evolved and population immunity has shifted. Method(s): Household contacts, enrolled from two multi-site case-ascertained household transmission studies (April 2020-April 2021 and September 2021-September 2022), were followed for 10-14 days after enrollment with daily collection of nasal swabs and/or saliva for SARS-CoV-2 testing and symptom diaries. SARS-CoV-2 virus lineage was determined by whole genome sequencing, with multiple imputation where sequences could not be recovered. Adjusted infection risks were estimated using modified Poisson regression. Finding(s): 858 primary cases with 1473 household contacts were examined. Among unvaccinated household contacts, the infection risk adjusted for presence of prior infection and age was 58% (95% confidence interval [CI]: 49-68%) in households currently exposed to pre-Delta lineages and 90% (95% CI: 74-100%) among those exposed to Omicron BA.5 (detected May - September 2022). The fraction of infected household contacts reporting any symptom was similarly high between pre-Delta (86%, 95% CI: 81-91%) and Omicron lineages (77%, 70-85%). Among Omicron BA.5-infected contacts, 48% (41-56%) reported fever, 63% (56-71%) cough, 22% (17-28%) shortness of breath, and 20% (15-27%) loss of/change in taste/smell. Interpretation(s): The risk of infection among household contacts exposed to SARS-CoV-2 is high and increasing with more recent SARS-CoV-2 lineages. This high infection risk highlights the importance of vaccination to prevent severe disease. Funding(s): Funded by the Centers for Disease Control and Prevention and the Food and Drug Administration. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available for use under a CC0 license.

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.

In a cohort of essential workers in the United States previously infected with SARS-CoV-2, risk factors for reinfection included being unvaccinated, infrequent mask use, time since first infection, and being non-Hispanic Black. Protecting workers from reinfection requires a multipronged approach including up-to-date vaccination, mask use as recommended, and reduction in underlying health disparities.

The purpose of this document is to highlight practical recommendations to assist acute-care hospitals in prioritization and implementation of strategies to prevent healthcare-associated infections through hand hygiene. This document updates the Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals through Hand Hygiene, published in 2014. This expert guidance document is sponsored by the Society for Healthcare Epidemiology (SHEA). It is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America, the Association for Professionals in Infection Control and Epidemiology, the American Hospital Association, and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise.

IMPORTANCE: Influenza virus infections declined globally during the COVID-19 pandemic. Loss of natural immunity from lower rates of influenza infection and documented antigenic changes in circulating viruses may have resulted in increased susceptibility to influenza virus infection during the 2021-2022 influenza season. OBJECTIVE: To compare the risk of influenza virus infection among household contacts of patients with influenza during the 2021-2022 influenza season with risk of influenza virus infection among household contacts during influenza seasons before the COVID-19 pandemic in the US. DESIGN, SETTING, AND PARTICIPANTS: This prospective study of influenza transmission enrolled households in 2 states before the COVID-19 pandemic (2017-2020) and in 4 US states during the 2021-2022 influenza season. Primary cases were individuals with the earliest laboratory-confirmed influenza A(H3N2) virus infection in a household. Household contacts were people living with the primary cases who self-collected nasal swabs daily for influenza molecular testing and completed symptom diaries daily for 5 to 10 days after enrollment. EXPOSURES: Household contacts living with a primary case. MAIN OUTCOMES AND MEASURES: Relative risk of laboratory-confirmed influenza A(H3N2) virus infection in household contacts during the 2021-2022 season compared with prepandemic seasons. Risk estimates were adjusted for age, vaccination status, frequency of interaction with the primary case, and household density. Subgroup analyses by age, vaccination status, and frequency of interaction with the primary case were also conducted. RESULTS: During the prepandemic seasons, 152 primary cases (median age, 13 years; 3.9% Black; 52.0% female) and 353 household contacts (median age, 33 years; 2.8% Black; 54.1% female) were included and during the 2021-2022 influenza season, 84 primary cases (median age, 10 years; 13.1% Black; 52.4% female) and 186 household contacts (median age, 28.5 years; 14.0% Black; 63.4% female) were included in the analysis. During the prepandemic influenza seasons, 20.1% (71/353) of household contacts were infected with influenza A(H3N2) viruses compared with 50.0% (93/186) of household contacts in 2021-2022. The adjusted relative risk of A(H3N2) virus infection in 2021-2022 was 2.31 (95% CI, 1.86-2.86) compared with prepandemic seasons. CONCLUSIONS AND RELEVANCE: Among cohorts in 5 US states, there was a significantly increased risk of household transmission of influenza A(H3N2) in 2021-2022 compared with prepandemic seasons. Additional research is needed to understand reasons for this association.

BACKGROUND: Three doses of coronavirus disease 2019 (COVID-19) messenger RNA (mRNA) vaccines produce robust antibody responses, but data are limited among individuals previously infected with SARS-CoV-2. From a cohort of health care personnel (75.5%), first responders (4.6%), and other frontline workers (19.8%) in 6 US states, we longitudinally assessed antibody waning after dose-2, and response to dose-3, according to SARS-CoV-2 infection history. METHODS: Participants submitted sera every three months, after SARS-CoV-2 infection, and after each COVID-19 vaccine dose. Sera were tested for antibodies and reported quantitatively as area under the serial dilution curve (AUC). Changes in the AUC values over time were compared as fold-changes using a linear mixed model. RESULTS: Analysis included 388 participants who received dose-3 by November 2021. Three comparison groups: (1) vaccine only with no known prior SARS-CoV-2 infection (n = 224); (2) infection prior to dose-1 (n = 123); and (3) infection after dose 2 and before dose-3 (n = 41). The interval from dose 2 and dose 3 was approximately 8-months. After dose-3, antibody levels rose 2.5-fold (95%CI = 2.2-3.0) in group 2, and 2.9-fold (95%CI = 2.6-3.3) in group 1. Those infected within 90 days before dose-3 (and median 233 days (IQR = 213-246) after dose-2) did not increase significantly after dose-3. CONCLUSIONS: A third dose of mRNA vaccine typically elicited a robust humoral immune response among those with primary vaccination regardless of SARS-CoV-2 infection >3 months prior to boosting. Those with infection < 3 months prior to boosting did not have a significant increase in antibody concentrations in response to a booster.

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/L; difference, -1.0 [95% CI, -1.7 to -0.2] for Delta and 2.8 vs 3.5 log10 copies/L, 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.

What is already known on this topic? In June 2022, COVID-19 vaccines were authorized for use in children aged 6 months-5 years. Intent to vaccinate and vaccination rates in children have been low. What is added by this report? During July 2021-May 2022, in a longitudinal cohort of 393 children aged <5 years in four states, parental intent to vaccinate children against COVID-19 and perception of COVID-19 vaccine safety and effectiveness declined over a 3-month period, but intent to vaccinate and perceptions of vaccine safety returned to baseline after 6 months. What are the implications for public health practice? Identifying and addressing barriers to COVID-19 vaccination in children aged <5 years and educating parents about COVID-19 vaccine effectiveness and safety in young children are critical to increasing pediatric COVID-19 vaccination coverage. © 2022 Department of Health and Human Services. All rights reserved.

BACKGROUND: Assessing the real-world effectiveness of COVID-19 vaccines and understanding the incidence and severity of SARS-CoV-2 illness in children is essential to inform policy and guide healthcare professionals 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 and aims to enroll approximately 2,305 children across four U.S. locations and collect data over a two-year surveillance period; the enrollment target was based on prospective power calculations and account for expected attrition and nonresponse. Study sites recruit parents and legal guardians (PLGs) of age-eligible children participating in the existing HEROES-RECOVER network as well as from surrounding communities. Child demographics, medical history, COVID-19 exposure, vaccination history, and PLGs' knowledge and attitudes about COVID-19 are collected at baseline and throughout the study. Mid-turbinate nasal specimens are self- or PLG-collected 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 their PLG's permission, 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 records (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 Spring 2023. As of 05/13/2022, 2,371 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.

Data are needed regarding the effectiveness of a third dose of a messenger RNA (mRNA) vaccine against the B.1.1.529 (omicron) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that are based on scientifically rigorous, population-level surveillance. Health care personnel, first responders, and other essential and frontline workers who are being evaluated in the HEROES-RECOVER cohorts at eight sites in six states across the United States underwent weekly reverse-transcriptase–polymerase-chain-reaction (RT-PCR) testing regardless of the presence or absence of coronavirus disease 2019 (Covid-19) symptoms.1-3 Here, we report the vaccine effectiveness of two or three doses of an mRNA vaccine against infection caused by the omicron and B.1.617.2 (delta) variants.

The BNT162b2 (Pfizer-BioNTech) mRNA COVID-19 vaccine was recommended by CDC's Advisory Committee on Immunization Practices for persons aged 12-15 years (referred to as adolescents in this report) on May 12, 2021, and for children aged 5-11 years on November 2, 2021 (1-4). Real-world data on vaccine effectiveness (VE) in these age groups are needed, especially because when the B.1.1.529 (Omicron) variant became predominant in the United States in December 2021, early investigations of VE demonstrated a decline in protection against symptomatic infection for adolescents aged 12-15 years and adults* (5). The PROTECT(†) prospective cohort of 1,364 children and adolescents aged 5-15 years was tested weekly for SARS-CoV-2, irrespective of symptoms, and upon COVID-19-associated illness during July 25, 2021-February 12, 2022. Among unvaccinated participants (i.e., those who had received no COVID-19 vaccine doses) with any laboratory-confirmed SARS-CoV-2 infection, those with B.1.617.2 (Delta) variant infections were more likely to report COVID-19 symptoms (66%) than were those with Omicron infections (49%). Among fully vaccinated children aged 5-11 years, VE against any symptomatic and asymptomatic Omicron infection 14-82 days (the longest interval after dose 2 in this age group) after receipt of dose 2 of the Pfizer-BioNTech vaccine was 31% (95% CI = 9%-48%), adjusted for sociodemographic characteristics, health information, frequency of social contact, mask use, location, and local virus circulation. Among adolescents aged 12-15 years, adjusted VE 14-149 days after dose 2 was 87% (95% CI = 49%-97%) against symptomatic and asymptomatic Delta infection and 59% (95% CI = 22%-79%) against Omicron infection. Fully vaccinated participants with Omicron infection spent an average of one half day less sick in bed than did unvaccinated participants with Omicron infection. All eligible children and adolescents should remain up to date with recommended COVID-19 vaccinations.

BACKGROUND: Adult residents of skilled nursing facilities (SNF) have experienced high morbidity and mortality from SARS-CoV-2 infection and are at increased risk for severe COVID-19 disease. Use of monoclonal antibody (mAb) treatment improves clinical outcomes among high-risk outpatients with mild-to-moderate COVID-19, but information on mAb effectiveness in SNF residents with COVID-19 is limited. We assessed outcomes in SNF residents with mild-to-moderate COVID-19 associated with an outbreak in Arizona during January-February 2021 that did and did not receive a mAb. METHODS: Medical records were reviewed to describe the effect of bamlanivimab therapy on COVID-19 mortality. Secondary outcomes included referral to an acute care setting and escalation of medical therapies at the SNF (e.g., new oxygen requirements). Residents treated with bamlanivimab were compared to residents who were eligible for treatment under the FDA's Emergency Use Authorization (EUA) but were not treated. Multivariable logistic regression was used to determine association between outcomes and treatment status. RESULTS: Seventy-five residents identified with COVID-19 during this outbreak met eligibility for mAb treatment, of whom 56 received bamlanivimab. Treated and untreated groups were similar in age and comorbidities associated with increased risk of severe COVID-19 disease. Treatment with bamlanivimab was associated with reduced 21-day mortality (adjusted OR=0.06; 95% CI: 0.01, 0.39) and lower odds of initiating oxygen therapy (adjusted OR=0.07; 95% CI: 0.02, 0.34). Referrals to acute care were not significantly different between treated and untreated residents. CONCLUSIONS: mAb therapy was successfully administered to SNF residents with COVID-19 in a large outbreak setting. Treatment with bamlanivimab reduced 21-day mortality and reduced initiation of oxygen therapy. As the COVID-19 pandemic evolves and newer immunotherapies gain FDA authorization, more studies of the effectiveness of mAb therapies for treating emerging SARS-CoV-2 variants of concern in high-risk congregate settings are needed. This article is protected by copyright. All rights reserved.

BACKGROUND: We sought to evaluate the impact of changes in estimates of COVID-19 vaccine effectiveness on the incidence of laboratory-confirmed infection among frontline workers at high risk for SARS-CoV-2. METHODS: We analyzed data from a prospective frontline worker cohort to estimate the incidence of COVID-19 by month as well as the association of COVID-19 vaccination, occupation, demographics, physical distancing, and mask use with infection risk. Participants completed baseline and quarterly surveys, and each week self-collected mid-turbinate nasal swabs and reported symptoms. RESULTS: Among 1018 unvaccinated and 3531 fully vaccinated workers, the monthly incidence of laboratory-confirmed SARS-CoV-2 infection in January 2021 was 13.9 (95% confidence interval [CI]: 10.4-17.4), declining to 0.5 (95% CI -0.4-1.4) per 1000 person-weeks in June. By September 2021, when the Delta variant predominated, incidence had once again risen to 13.6 (95% CI 7.8-19.4) per 1000 person-weeks. In contrast, there was no reportable incidence among fully vaccinated participants at the end of January 2021, and incidence remained low until September 2021 when it rose modestly to 4.1 (95% CI 1.9-3.8) per 1000. Below average facemask use was associated with a higher risk of infection for unvaccinated participants during exposure to persons who may have COVID-19 and vaccinated participants during hours in the community. CONCLUSIONS: COVID-19 vaccination was significantly associated with a lower risk of SARS-CoV-2 infection despite Delta variant predominance. Our data demonstrate the added protective benefit of facemask use among both unvaccinated and vaccinated frontline workers.

The BNT162b2 (Pfizer-BioNTech) mRNA COVID-19 vaccine has demonstrated high efficacy in preventing infection with SARS-CoV-2 (the virus that causes COVID-19) in randomized placebo-controlled Phase III trials in persons aged 12-17 years (referred to as adolescents in this report) (1); however, data on real-word vaccine effectiveness (VE) among adolescents are limited (1-3). As of December 2021, the Pfizer-BioNTech vaccine is approved by the Food and Drug Administration (FDA) for adolescents aged 16-17 years and under FDA emergency use authorization for those aged 12-15 years. In a prospective cohort in Arizona, 243 adolescents aged 12-17 years were tested for SARS-CoV-2 by reverse transcription-polymerase chain reaction (RT-PCR) each week, irrespective of symptoms, and upon onset of COVID-19-like illness during July 25-December 4, 2021; the SARS-CoV-2 B.1.617.2 (Delta) variant was the predominant strain during this study period. During the study, 190 adolescents contributed fully vaccinated person-time (≥14 days after receiving 2 doses of Pfizer-BioNTech vaccine), 30 contributed partially vaccinated person-time (receipt of 1 dose or receipt of 2 doses but with the second dose completed <14 days earlier), and 66 contributed unvaccinated person-time. Using the Cox proportional-hazards model, the estimated VE of full Pfizer-BioNTech vaccination for preventing SARS-CoV-2 infection was 92% (95% CI = 79%-97%), adjusted for sociodemographic characteristics, health information, frequency of social contact, mask use, location, and local virus circulation. These findings from a real-world setting indicate that 2 doses of Pfizer-BioNTech vaccine are highly effective in preventing SARS-CoV-2 infection among Arizona adolescents. CDC recommends COVID-19 vaccination for all eligible persons in the United States, including persons aged 12-17 years.

IMPORTANCE: Understanding the relative risk of SARS-CoV-2 infection across occupations can inform guidance to protect workers and communities. Less is known about infection risk for first responders and other essential workers than for health care personnel. OBJECTIVE: To compare the prevaccination incidence of SARS-CoV-2 infection among first responders and other essential workers with incidence among health care personnel. DESIGN SETTING AND PARTICIPANTS: This was a prospective cohort study of health care personnel, first responders, and other essential workers in Arizona from July 20, 2020, to March 14, 2021. Participants were seronegative at enrollment, had frequent direct contact with others at work, worked at least 20 hours per week, and submitted weekly nasal swab specimens for real-time reverse transcriptase polymerase chain reaction analysis. Data analyses were performed from April 19, 2021, to June 4, 2021. EXPOSURES: Occupation was the primary exposure of interest. Confounders assessed were sociodemographic characteristics, health status, community exposure, and work exposure. MAIN OUTCOMES AND MEASURES: Crude incidence of SARS-CoV-2 infection was defined as the sum of first positive SARS-CoV-2 infections in participants divided by person-weeks at risk. Negative binomial regression was used to model SARS-CoV-2 infection by occupation to estimate unadjusted and adjusted incidence rate ratios (IRRs). The least absolute shrinkage and selection operator (LASSO) method was used to generate a parsimonious multivariable model. RESULTS: The study cohort comprised 1766 Arizona workers (mean age [SD], 43.8 [11.1] years; 1093 [61.9%] female; 401 [22.7%] were Hispanic and 1530 [86.6%] were White individuals) of whom 44.2% were health care personnel, 22.4% first responders, and 33.4% other essential workers. The cohort was followed up for 23 393 person-weeks. Crude incidence of SARS-CoV-2 infection was 6.7, 13.2, and 7.4 per 1000 person-weeks at risk for health care personnel, first responders, and other essential workers, respectively. In unadjusted models, first responders had twice the incidence of infection as health care personnel (IRRs, 2.01; 95% CI, 1.44-2.79). While attenuated, this risk remained elevated in adjusted LASSO-optimized models (IRR, 1.60; 95% CI, 1.07-2.38). Risk of infection among other essential workers was no different than for health care personnel in unadjusted or adjusted models. CONCLUSIONS AND RELEVANCE: This prospective cohort study found that first responders had a higher incidence of SARS-CoV-2 infection than health care personnel, even after adjusting for potential confounding factors. Given their frequent contact with each other and with the public and their high rates of SARS-CoV-2 infection, the safety challenges for first responders warrant greater public health attention and research.

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).