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With the exponential growth in investment attention to brain health—solutions spanning brain wellness to mental health to neurological disorders—tech giants, payers, and biotechnology companies have been making forays into this field to identify technology solutions and pharmaceutical amplifiers. So far, their investments have had mixed results. The concept of open innovation (OI) was first coined by Henry Chesbrough to describe the paradigm by which enterprises allow free flow of ideas, products, and services from the outside to the inside and vice versa in order to remain competitive, particularly in rapidly evolving fields where there is abundant, relevant knowledge outside the traditional walls of the enterprise. In this article, we advocate for further exploration and advancement of OI in brain health.
Water stress and weed competition are critical stressors during corn (Zea mays L.) development. Genetic improvements in corn have resulted in hybrids with greater tolerance to abiotic and biotic stressors; however, drought stress remains problematic. Therefore, in light of the anticipated change in precipitation throughout the Great Lakes Region, greenhouse experiments were conducted to evaluate water stress and weed competition on drought-tolerant corn performance. The study followed a completely randomized block design with four replications. Factorial treatment combinations consisted of drought-tolerant corn competition (presence or absence), water stress (100% or 50% volumetric water content [VWC]), and nine corn:common lambsquarters (Chenopodium album L., CHEAL) densities. Corn and C. album growth parameters were measured at 14 and 21 d after water-stress initiation. To explore the impact of reduced soil moisture and weed competition on corn and C. album growth parameters, photosynthetic response, and biomass, linear mixed-effects and nonlinear regression models were constructed in R. Chenopodium album biomass was reduced by 46% and 50% under corn competition at 2 and 4 weeds pot−1 (P = 0.0003, 0.0004). However, introducing crop competition under 6 and 9 weeds pot−1 did not reduce C. album biomass (P = 0.90, 1.00). Averaged across weed pressures, corn biomass was 22% less when grown under 50% compared with 100% VWC (P = 0.0003). However, averaged across VWC values, increasing weed competition from 0 to 2 (P = 0.04), 4 (P = <0.0001), 6 (P = 0.0002), or 9 (P = 0.0002) weeds pot−1 reduced biomass by 22%, 38%, 35%, and 36%. Overall, water stress and C. album competition negatively affected the parameters measured in this study; however, the magnitude of reduction is stronger under drought stress than increasing weed competition when water is not limiting. Therefore, field crop growers must modify current integrated weed management programs to maintain yield under future climate stress.
Background: Central-line–associated bloodstream infections (CLABSIs) arise from bacteria migrating from the skin along the catheter, by direct inoculation, or from pathogens that form biofilms on the interior surface of the catheter. However, given the oxygen-poor environments that obligate anaerobes require, these organisms are unlikely to survive long enough on the skin or on the catheter after direct inoculation to be the true cause of a CLABSI. Although some anaerobic CLABSIs may meet the definition for a mucosal-barrier-injury, laboratory-confirmed, bloodstream infection (MBI-LCBI), some may be not. We sought to determine the proportion of CLABSIs attributed to obligate anaerobic bacteria, and we sought to determine the pathophysiologic source of these infections. Methods: We performed a retrospective analysis of prospectively collected CLABSI data at 54 hospitals (academic and community) in the southeastern United States from January 2015 to December 2020. We performed chart reviews on a convenient sample for which medical records were available. We calculated the proportion of CLABSIs due to obligate anaerobes, and we have described a subset of anaerobic CLABSI cases. Results: We identified 60 anaerobic CLABSIs of 2,430 CLABSIs (2.5%). Of the 60 anaerobic CLABSIs, 7 were polymicrobial with nonanaerobic bacteria. The most common species we identified were Bacteroides, Clostridium, and Lactobacillus (Table 1). The proportion of anaerobic CLABSIs per year varied from 1.2% to 3.7% (Fig. 1). Of 60 anaerobic CLABSIs, 29 (48%) occurred in the only quaternary-care academic medical center in the database. In contrast, an average of 0.6 (SD, 0.6) anaerobic CLABSIs occurred in the 53 community hospitals over the 6-year study period. Of these 29 anaerobic CLABSIs, 23 (79%) were clinically consistent with secondary bloodstream infections (BSIs) due to gastrointestinal or genitourinary source, but they lacked appropriate documentation to meet NHSN criteria for secondary BSI or MBI-LCBI based on case reviews by infection prevention physicians. The other 6 anaerobic CLABSIs did not have a clear clinical etiology and did not meet MBI-LCBI criteria. In addition, 27 (93%) of 29 anaerobic CLABSIs occurred in patients who were either solid-organ transplant recipients, were stem-cell transplant recipients, or were receiving chemotherapy. Lastly, 27 (93%) of 29 anaerobic CLABSIs were treated with antibiotics. Conclusions: Anaerobic CLABSIs are uncommon events, but CLABSI may disproportionately affect large, academic hospitals caring for a high proportion of medically complex patients. Additional criteria could be added to the MBI-LCBI to better classify anaerobic BSI.
Background: Racial and ethnic disparities in healthcare access, medical treatment, and outcomes have been extensively reported. However, the impact of racial and ethnic differences in patient safety, including healthcare-associated infections, has not been well described. Methods: We performed a retrospective review analyzing prospectively collected data on central-line–associated bloodstream infection (CLABSI) and catheter-associated urinary tract infection (CAUTI) rates per 1,000 device days. Data for adult patients admitted to an academic medical center between 2018 and 2021 were stratified by 7 racial and ethnic groups: non-Hispanic White, non-Hispanic Black, Hispanic/Latino, Asian, American Indian/Alaska Native, Native Hawaiian/Pacific Islander, and othe. The “other” group was composed of bi- or multiracial patients, or those for whom no data were reported. We compared the CLABSI and CAUTI rates between the different racial and ethnic groups using Poisson regression. Results: Compared to non-Hispanic White patients, the rate of CLABSI was significantly higher in non-Hispanic Black patients (1.27; 95% CI, 1.02–1.58; P < .03) and those in the “other” race category (1.79; 95% CI, 1.39–2.30; P < .001, respectively), and these trends increased in Hispanic/Latino patients (Table 1). Similarly, Black patients had higher rates of CAUTI (1.42; 95% CI, 1.05–1.92; P < .02), as did Asian patients (2.49; 95% CI, 1.16–5.36; P < .02), and patients in the “other” category (1.52; 95% CI, 1.06–2.18; P < .02) (Table 2). Conclusions: Racial and ethnic minorities may be vulnerable to a higher rate of patient safety events, including CLABSIs and CAUTIs. Additional analyses controlling for potential confounding factors are needed to better understand the relationship between race or ethnicity, clinical management, and healthcare-associated infections. This evaluation is essential to inform mitigation strategies and to provide optimum, equitable care for all.
Using physiological markers to detect patients at risk of deterioration is common. Deaths at music festivals in Australia prompted scrutiny of tools to identify critically unwell patients for transport to hospital. This study evaluated initial physiological parameters to identify patients selected for transport to hospital from a music festival.
A retrospective audit of 2045 presentations at music festivals in Victoria, Australia, was performed. Presentation heart rate, systolic blood pressure, respiratory rate, oxygen saturation, temperature, and Glasgow Coma Scale were assessed using area under the receiver operating characteristic curve (AUROC) analysis, with a prespecified threshold of 0.7.
The only measured variable to exceed the prespecified cutpoint was initial systolic blood pressure, with an AUROC of 0.72 and optimal cutpoint of 122 mmHg. Using commonly accepted cutpoints for variables did not improve detection performance to acceptable levels, nor did using combination systems of cutpoints.
Initial physiological variables are poor predictors of the decision to transport to hospital from music festivals. Systolic blood pressure was significant, but only at a clinically insignificant value. Decisions on which patients to transport from an event site should incorporate more information than initial physiology. Senior clinicians should lead decision-making about hospital transport from music festivals.
The 2019-2020 “Black Summer” bushfires in Australia focused the attention of the nation on the critical role that volunteer firefighters play in the response to such a disaster, spurring a national conversation about how to best support those on the frontline. The objective of this research was to explore the impact of the Black Summer bushfires on volunteer firefighter well-being and to investigate how to deliver effective well-being support.
An explorative qualitative design underpinned by a phenomenological approach was applied. Participant recruitment followed a multi-modal sampling strategy and data were collected through semi-structured, in-depth interviews.
Qualitative data were collected from 58 participants aged from 23 to 61-years-of-age (average age of 46 years). All self-reported as volunteer firefighters who had responded to the Black Summer bushfires in Australia. Just over 80% of participants were male and the majority lived in the Australian states of New South Wales (65%) and Victoria (32%). All participants reported impact on their well-being, resulting from cumulative trauma exposure, responding to fires in local communities, intense work demands, minimal intervals between deployments, and disruption to primary employment. In regard to supporting well-being, four key themes emerged from data analysis: (1) Well-being support needs to be both proactive and reactive and empower local leaders to “reach in” while encouraging responders to “reach out;” (2) Employee Assistance Programs (EAPs) should not be the only well-being support option available; (3) The sharing of lived experience is important; and (4) Support programs need to address self-stigmatization.
Participants in this research identified that effective well-being support needs to be both proactive and reactive and holistic in approach.
A substantial body of research exists regarding vicarious trauma (VT) exposure among helping professionals across disciplines and settings. There is limited research, however, on exposure to VT in qualitative researchers studying traumatized populations. The objective of this study was to explore the experiences of qualitative researchers who study traumatized populations and to identify potential protective strategies for reducing the risk of VT.
The study utilized a qualitative methodological design. Focus groups and in-depth interviews were conducted using a semi-structured script. Thematic analysis was conducted to identify both risk factors and protective factors associated with VT. A sample of 58 research participants were recruited using a multimodal recruitment strategy.
Using thematic analysis, the following key themes emerged: exposure to primary trauma, the impact of stigma, organizational context, individual context, and research context. The opportunity for posttraumatic growth was also identified.
Qualitative researchers of traumatized populations need to recognize the potential for VT and implement appropriate protection strategies from the risk of VT. The development of policies and guidelines that recognize the importance of both self-care and plan for researcher safety and well-being is a potential strategy for building researcher resilience and preventing VT.
As the understanding of health care worker lived experience during coronavirus disease 2019 (COVID-19) grows, the experiences of those utilizing emergency health care services (EHS) during the pandemic are yet to be fully appreciated.
The objective of this research was to explore lived experience of EHS utilization in Victoria, Australia during the COVID-19 pandemic from March 2020 through March 2021.
An explorative qualitative design underpinned by a phenomenological approach was applied. Data were collected through semi-structured, in-depth interviews, which were transcribed verbatim and analyzed using Colaizzi’s approach.
Qualitative data were collected from 67 participants aged from 32 to 78-years-of-age (average age of 52). Just over one-half of the research participants were male (54%) and three-quarters lived in metropolitan regions (75%). Four key themes emerged from data analysis: (1) Concerns regarding exposure and infection delayed EHS utilization among participants with chronic health conditions; (2) Participants with acute health conditions expressed concern regarding the impact of COVID-19 on their care, but continued to access services as required; (3) Participants caring for people with sensory and developmental disabilities identified unique communication needs during interactions with EHS during the COVID-19 pandemic; communicating with emergency health care workers wearing personal protective equipment (PPE) was identified as a key challenge, with face masks reported as especially problematic for people who are deaf or hard-of-hearing; and (4) Children and older people also experienced communication challenges associated with PPE, and the need for connection with emergency health care workers was important for positive lived experience during interactions with EHS throughout the pandemic.
This research provides an important insight into the lived experience of EHS utilization during the COVID-19 pandemic, a perspective currently lacking in the published peer-reviewed literature.
The majority of research investigating healthcare workers’ (HCWs) willingness to work during public health emergencies, asks participants to forecast their perceptions based on hypothetical emergencies, rather than in response to the actual public health emergencies they have experienced. This research explored frontline HCWs willingness to work during Australia’s first wave of the COVID-19 pandemic among frontline HCWs.
Participants (n = 580) completed an online questionnaire regarding their willingness to work during the pandemic.
A total of 42% of participants reported being less willing to work during the pandemic compared to before. Availability of personal protective equipment (PPE), concern expressed by family members, and viral exposure were significant barriers. A third of participants disagreed that some level of occupational risk for exposure to infectious disease was acceptable while a quarter of participants had received communications from their workplace concerning obligations to work during COVID-19.
The COVID-19 pandemic has impacted Australian frontline HCWs’ willingness to work. Scarcity of PPE and exposure to the virus were the most cited reasons impacting on willingness to work. Appropriate policies and practices should be implemented and communicated efficiently to frontline HCW’s. This research provides insight into the lived experiences of Australian healthcare professionals’ willingness to work during a pandemic.
In a single day, the September 11, 2001 US terrorist attacks (9/11) killed nearly 3,000 people, including 412 first responders. More than 91,000 responders were exposed to a range of hazards during the recovery and clean-up operation that followed. Various health programs track the on-going health effects of 9/11, including the World Trade Center (WTC) Health Program (WTCHP). The objective of this research was to review WTCHP statistics reported by the Centers for Disease Control and Prevention (CDC) to analyze health trends among enrolled responders as the 20-year anniversary of the terrorist attacks approaches.
The WTCHP statistics reported by the CDC were analyzed to identify health trends among enrolled responders from 2011 through 2021. Statistics for non-responders were excluded.
A total of 80,745 responders were enrolled in the WTCHP as of March 2021: 62,773 were classified as general responders; 17,023 were Fire Department of New York (FDNY) responders; and 989 were Pentagon and Shanksville responders. Of the total responders in the program, 3,439 are now deceased. Just under 40% of responders with certified health issues were aged 45-64 and 83% were male. The top three certified conditions among enrolled responders were: aerodigestive disorders; cancer; and mental ill health. The top ten certified cancers have remained the same over the last five years, however, leukemia has now overtaken colon and bladder cancer as the 20-year anniversary approaches. Compared to the general population, 9/11 first responders had a higher rate of all cancers combined, as well as higher rates of prostate cancer, thyroid cancer, and leukemia.
Trends in these program statistics should be viewed with some caution. While certain illnesses have been linked with exposure to the WTC site, differences in age, sex, ethnicity, smoking status, and other factors between exposed and unexposed groups should also be considered. Increased rates of some illnesses among this cohort may be associated with heightened surveillance rather than an actual increase in disease. Still, cancer in general, as well as lung disease, heart disease, and posttraumatic stress disorder (PTSD), seem to be increasing among 9/11 responders, even now close to 20 years later.
Responders should continue to avail themselves of the health care and monitoring offered through programs like the WTCHP.
The state of California, in the United States of America, has a population of nearly 40 million people and is the 5th largest economy in the world. During the coronavirus disease 2019 (COVID-19) pandemic in 2020-2021, the state experienced a medical surge that stressed its sophisticated health-care and public health system. During this period, ventilators, oxygen, and other equipment necessary for providing ventilatory support became a scarce resource in many health-care settings. When demand overwhelms supply, creative solutions are required at all levels of disaster management and health care. This study describes the disaster response by the state of California to mitigate the emergency demands for oxygen delivery resources.
Physical health of psychiatric inpatients is worse than the general population. Physical health monitoring of these patients can have positive effects on outcomes. Birmingham and Solihull Mental Health Foundation Trust (BSMHFT) states that a physical health assessment (PHA) should be completed within 72 hours of admission. This comprises a physical health form (PHF) and minimum data set (MDS): BP, BMI, TB and BBV status, alcohol and drug screen, smoking status, Hba1c and lipids. In a 2017 audit, compliance was shown to need improvement, with 28.3% of admissions not having a PHF documented.
To assess whether PHAs for new admissions to the Oleaster, Birmingham during the first wave of COVID-19 were completed in line with trust policy
To compare findings with a previous audit
To make recommendations to improve inpatient physical health and compliance with trust policy
A retrospective audit was conducted, with PHA details accessed via the electronic medical records system RiO. Admissions from 16/03/2020-30/06/2020 were accessed and 158 admissions (155 patients) were included. 21 admissions were excluded as they were internal transfers; only data from the initial admission were included. Data were collected by 2 medical students and a psychiatry trainee using a data collection tool. Data were recorded and analysed on Excel.
Of 158 admissions, 81 had PHFs (51.3%). 59 were completed within 72 hours of admission (34.3%); 39 were completed fully (24.7%). Of incomplete PHFs, 2 explicitly stated incompletion due to COVID-19. 22 PHFs were created but not completed within 72 hours. 15 gave a deferral reason e.g., refusal to consent or agitation. For 77 admissions (47.3%), no assessment was documented, with no reason given.
2 admissions (1.3%) recorded the full MDS within 72 hours of admission.
2 admissions (1.3%) had fully complete PHAs (PHF and MDS) within 72 hours of admission, fulfilling trust policy.
51.3% of admissions had a PHF, with 34.3% documented within 72 hours of admission. However, only 1.3% of admissions fulfilled trust policy of both a completed PHF and MDS within 72 hours of admission. There were more admissions without a PHF than in the previous 2017 audit; 47.33% compared to 28.3% previously. Given trust targets that a PHA should be fully completed for 100% of admissions, it was found that the Oleaster did not meet these guidelines during this period and improvements must be made to maintain integrity of patient care.
First responders are at greater risk of mental ill health and compromised well-being compared to the general population. It is important to identify strategies that will be effective in supporting mental health, both during and after the first responder’s career.
A scoping review was conducted using the PubMed database (1966 to October 1, 2020) and the Google Scholar database (October 1, 2020) using relevant search terms, truncation symbols, and Boolean combination functions. The reference lists of all relevant publications were also reviewed to identify further publications.
A total of 172 publications were retrieved by the combined search strategies. Of these, 56 met the inclusion criteria and informed the results of this overview paper. These publications identified that strategies supporting first responder mental health and well-being need to break down stigma and build resilience. Normalizing conversations around mental health is integral for increasing help-seeking behaviors, both during a first responder’s career and in retirement. Organizations should consider the implementation of both pre-retirement and post-retirement support strategies to improve mental health and well-being.
Strategies for supporting mental health and well-being need to be implemented early in the first responder career and reinforced throughout and into retirement. They should utilize holistic approaches which encourage “reaching in” rather than placing an onus on first responders to “reach out” when they are in crisis.
The National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) are studying how samples might be brought back to Earth from Mars safely. Backward planetary protection is key in this complex endeavour, as it is required to prevent potential adverse effects from returning materials to Earth's biosphere. As the question of whether or not life exists on Mars today or whether it ever did in the past is still unanswered, the effort to return samples from Mars is expected to be categorized as a ‘Restricted Earth Return’ mission, for which NASA policy requires the containment of any unsterilized material returned to Earth. NASA is investigating several solutions to contain Mars samples and sterilize any uncontained Martian particles. This effort has significant implications for both NASA's scientific mission, and the Earth's environment; and so special care and vigilance are needed in planning and execution in order to assure acceptance of safety to Earth's biosphere. To generate a technically acceptable sterilization process across a wide array of scientific and other stakeholders, on 30–31 January 2019, 10–11 June 2019 and 19–20 February 2020, NASA informally convened a Sterilization Working Group (SWG) composed of experts from industry, academia and government to assess methods for sterilization and inactivation, to identify future work needed to verify these methods against biological challenges, and to determine their feasibility for implementation on robotic spacecraft in deep space. The goals of the SWG were:
(1) Understand what it means to sterilize and/or inactivate Martian materials and how that understanding can be applied to the Mars Sample Return (MSR) mission.
(2) Assess methods for sterilization and inactivation, and identify future work needed to verify these methods.
(3) Provide an effective plan for communicating with other agencies and the public.
This paper provides a summary of the discussions and conclusions of the SWG over these three workshops. It reflects a consensus position based on qualitative discussion of how agencies might approach the problem of sterilization of Mars material. The SWG reached a consensus that sterilization options can be considered on the basis of biology as we know it, and that sterilization modalities that are effective on terrestrial materials and organisms should be part of the MSR planetary protection strategy. Conclusions pointed to several industry standards for sterilization to include heat, chemical, UV radiation and low-heat plasma. Technical trade-offs for each sterilization modality were discussed while simultaneously considering the engineering challenges and limitations for spaceflight. Future work includes more in-depth discussions on technical trade-offs of sterilization modalities, identifying and testing Earth analogue challenge organisms and proteinaceous molecules against chosen modalities, and executing collaborative agreements between NASA and external working group partners to help close data gaps, and to establish strong, scientifically grounded sterilization and inactivation standards for MSR.
To describe epidemiologic and genomic characteristics of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in a large skilled-nursing facility (SNF), and the strategies that controlled transmission.
Design, setting, and participants:
This cohort study was conducted during March 22–May 4, 2020, among all staff and residents at a 780-bed SNF in San Francisco, California.
Contact tracing and symptom screening guided targeted testing of staff and residents; respiratory specimens were also collected through serial point prevalence surveys (PPSs) in units with confirmed cases. Cases were confirmed by real-time reverse transcription–polymerase chain reaction testing for SARS-CoV-2, and whole-genome sequencing (WGS) was used to characterize viral isolate lineages and relatedness. Infection prevention and control (IPC) interventions included restricting from work any staff who had close contact with a confirmed case; restricting movement between units; implementing surgical face masking facility-wide; and the use of recommended PPE (ie, isolation gown, gloves, N95 respirator and eye protection) for clinical interactions in units with confirmed cases.
Of 725 staff and residents tested through targeted testing and serial PPSs, 21 (3%) were SARS-CoV-2 positive: 16 (76%) staff and 5 (24%) residents. Fifteen cases (71%) were linked to a single unit. Targeted testing identified 17 cases (81%), and PPSs identified 4 cases (19%). Most cases (71%) were identified before IPC interventions could be implemented. WGS was performed on SARS-CoV-2 isolates from 4 staff and 4 residents: 5 were of Santa Clara County lineage and the 3 others were distinct lineages.
Early implementation of targeted testing, serial PPSs, and multimodal IPC interventions limited SARS-CoV-2 transmission within the SNF.
This process evaluation aimed to understand factors affecting the implementation of a government-sponsored short message service (SMS) programme for delivering nutrition information to rural populations, including message access, acceptability and putting messages into action.
The study was nested within a larger randomised controlled trial. Cross-sectional data collection included structured surveys and in-depth interviews. Data were analysed for key trends and themes using Stata and ATLAS.ti software.
The study took place in Tanzania’s Mtwara region.
Surveys were conducted with 205 women and 93 men already enrolled in the randomised controlled trial. A sub-set of 30 women and 14 men participated in the in-depth interviews.
Among women relying on a spouse’s phone, sharing arrangements impeded regular SMS access; men were commonly away from home, forgot to share SMS or did not share them in women’s preferred way. Phone-owning women faced challenges related to charging their phones and defective handsets. Once SMS were delivered, most participants viewed them as trustworthy and comprehensible. However, economic conditions limited the feasibility of applying certain recommendations, such as feeding meat to toddlers. A sub-set of participants concurrently enrolled in an interpersonal counselling (IPC) intervention indicated that the SMS provided reminders of lessons learned during the IPC; yet, the SMS did not help participants contextualise information and overcome the challenges of putting that information into practice.
The challenges to accessing and implementing SMS services highlighted here suggest that such platforms may work well as one component of a comprehensive nutrition intervention, yet not as an isolated effort.
Social cognitive deficits can have many negative consequences, spanning social withdrawal to psychopathology. Prior work has shown that child maltreatment may associate with poorer social cognitive skills in later life. However, no studies have examined this association from early childhood into adolescence. Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC; n = 4,438), we examined the association between maltreatment (caregiver physical or emotional abuse; sexual or physical abuse), assessed repeatedly (every 1–3 years) from birth to age 9, and social cognitive skills at ages 7.5, 10.5, and 14 years. We evaluated the role of both the developmental timing (defined by age at exposure) and accumulation of maltreatment (defined as the number of occasions exposed) using a least angle regression variable selection procedure, followed by structural equation modeling. Among females, accumulation of maltreatment explained the most variation in social cognitive skills. For males, no significant associations were found. These findings underscore the importance of early intervention to minimize the accumulation of maltreatment and showcase the importance of prospective studies to understand the development of social cognition over time.
Tracing the flow of solid matter during an explosion requires a rugged tag that can be measured by a unique identifiable signature. Silica-covered semiconductor quantum dots (QDs) provide a unique and tunable photoluminescent signature that emits from within a sacrificial outer layer. Five types of silica-covered zinc sulfide QDs were synthesized and covalently bound to commercial luminescent powders. The combination of five dots and five powders enables a matrix of 25 unique tags. The tracers are shown to be tolerant of environments associated with chemical explosives and provides a unique tag to evaluate debris fields.
Background: Chlorhexidine bathing reduces bacterial skin colonization and prevents infections in specific patient populations. As chlorhexidine use becomes more widespread, concerns about bacterial tolerance to chlorhexidine have increased; however, testing for chlorhexidine minimum inhibitory concentrations (MICs) is challenging. We adapted a broth microdilution (BMD) method to determine whether chlorhexidine MICs changed over time among 4 important healthcare-associated pathogens. Methods: Antibiotic-resistant bacterial isolates (Staphylococcus aureus from 2005 to 2019 and Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae complex from 2011 to 2019) were collected through Emerging Infections Program surveillance in 2 sites (Georgia and Tennessee) or through public health reporting in 1 site (Orange County, California). A convenience sample of isolates were collected from facilities with varying amounts of chlorhexidine use. We performed BMD testing using laboratory-developed panels with chlorhexidine digluconate concentrations ranging from 0.125 to 64 μg/mL. After successfully establishing reproducibility with quality control organisms, 3 laboratories performed MIC testing. For each organism, epidemiological cutoff values (ECVs) were established using ECOFFinder. Results: Among 538 isolates tested (129 S. aureus, 158 E. coli, 142 K. pneumoniae, and 109 E. cloacae complex), S. aureus, E. coli, K. pneumoniae, and E. cloacae complex ECVs were 8, 4, 64, and 64 µg/mL, respectively (Table 1). Moreover, 14 isolates had an MIC above the ECV (12 E. coli and 2 E. cloacae complex). The MIC50 of each species is reported over time (Table 2). Conclusions: Using an adapted BMD method, we found that chlorhexidine MICs did not increase over time among a limited sample of S. aureus, E. coli, K. pneumoniae, and E. cloacae complex isolates. Although these results are reassuring, continued surveillance for elevated chlorhexidine MICs in isolates from patients with well-characterized chlorhexidine exposure is needed as chlorhexidine use increases.