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Abstract Background Environmental surfaces play an important role in transmission of healthcare-associated pathogens. There is a need for new disinfection methods that are effective against Clostridium difficile spores, but also safe and rapid. The Sterilray™ Disinfection Wand device is a hand-held room decontamination technology that utilizes far-ultraviolet radiation (185-230 nm) to kill pathogens. Methods We examined the efficacy of disinfection using the Sterilray device in the laboratory, in rooms of hospitalized patients, and on surfaces outside of patient rooms (i.e. keyboards and portable medical equipment). Cultures for C. difficile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE) were collected from commonly-touched surfaces before and after use of the Sterilray device. Results On inoculated surfaces in the laboratory, application of the Sterilray device at a radiant dose of 100 mJ/cm2 for ~ 5 seconds consistently reduced recovery of C. difficile spores by 4.4 CFU log10, MRSA by 5.4 log10CFU and of VRE by 6.9 log10CFU. A >3 log10 reduction of MRSA and VRE was achieved in ~2 seconds at a lower radiant dose, but killing of C. difficile spores was significantly reduced. On keyboards and portable medical equipment that were inoculated with C. difficile spores, application of the Sterilray device at a radiant dose of 100���mJ/cm2 for ~ 5 seconds reduced contamination by 3.2 log10CFU. However, the presence of organic material reduced the lethal effect of the far-UV radiation. In hospital rooms that were not pre-cleaned, disinfection with the Sterilray device significantly reduced the frequency of positive C. difficile and MRSA cultures (P =0.007). Conclusions The Sterilray™ Disinfection Wand is a novel environmental disinfection technology that rapidly kills C. difficile spores and other healthcare-associated pathogens on surfaces. However, the presence of organic matter reduces the efficacy of far-UV radiation, possibly explaining the more modest results observed on surfaces in hospital rooms that were not pre-cleaned. more...

Abstract Background Fluoroquinolones are among the most commonly prescribed antimicrobials and are an important risk factor for colonization and infection with fluoroquinolone-resistant gram-negative bacilli and for Clostridium difficile infection (CDI). In this study, our aim was to determine current patterns of inappropriate fluoroquinolone prescribing among hospitalized patients, and to test the hypothesis that longer than necessary treatment durations account for a significant proportion of unnecessary fluoroquinolone use. Methods We conducted a 6-week prospective, observational study to determine the frequency of, reasons for, and adverse effects associated with unnecessary fluoroquinolone use in a tertiary-care academic medical center. For randomly-selected adult inpatients receiving fluoroquinolones, therapy was determined to be necessary or unnecessary based on published guidelines or standard principles of infectious diseases. Adverse effects were determined based on chart review 6 weeks after completion of therapy. Results Of 1,773 days of fluoroquinolone therapy, 690 (39%) were deemed unnecessary. The most common reasons for unnecessary therapy included administration of antimicrobials for non-infectious or non-bacterial syndromes (292 days-of-therapy) and administration of antimicrobials for longer than necessary durations (234 days-of-therapy). The most common syndrome associated with unnecessary therapy was urinary tract infection or asymptomatic bacteriuria (30% of all unnecessary days-of-therapy). Twenty-seven percent (60/227) of regimens were associated with adverse effects possibly attributable to therapy, including gastrointestinal adverse effects (14% of regimens), colonization by resistant pathogens (8% of regimens), and CDI (4% of regimens). Conclusions In our institution, 39% of all days of fluoroquinolone therapy were unnecessary. Interventions that focus on improving adherence with current guidelines for duration of antimicrobial therapy and for management of urinary syndromes could significantly reduce overuse of fluoroquinolones. more...

Abstract Background Environmental surfaces play an important role in transmission of healthcare-associated pathogens. There is a need for new disinfection methods that are effective against Clostridium difficile spores, but also safe, rapid, and automated. Methods The Tru-D™ Rapid Room Disinfection device is a mobile, fully-automated room decontamination technology that utilizes ultraviolet-C irradiation to kill pathogens. We examined the efficacy of environmental disinfection using the Tru-D device in the laboratory and in rooms of hospitalized patients. Cultures for C. difficile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE) were collected from commonly touched surfaces before and after use of Tru-D. Results On inoculated surfaces, application of Tru-D at a reflected dose of 22,000 μWs/cm2 for ~45 minutes consistently reduced recovery of C. difficile spores and MRSA by >2-3 log10 colony forming units (CFU)/cm2 and of VRE by >3-4 log10 CFU/cm2. Similar killing of MRSA and VRE was achieved in ~20 minutes at a reflected dose of 12,000 μWs/cm2, but killing of C. difficile spores was reduced. Disinfection of hospital rooms with Tru-D reduced the frequency of positive MRSA and VRE cultures by 93% and of C. difficile cultures by 80%. After routine hospital cleaning of the rooms of MRSA carriers, 18% of sites under the edges of bedside tables (i.e., a frequently touched site not easily amenable to manual application of disinfectant) were contaminated with MRSA, versus 0% after Tru-D (P < 0.001). The system required Conclusions The Tru-D Rapid Room Disinfection device is a novel, automated, and efficient environmental disinfection technology that significantly reduces C. difficile, VRE and MRSA contamination on commonly touched hospital surfaces. more...

Abstract Background Intestinal colonization by Staphylococcus aureus among hospitalized patients has been associated with increased risk of staphylococcal infection and could potentially contribute to transmission. We hypothesized that S. aureus intestinal colonization is associated with increased frequency of S. aureus on patients' skin and nearby environmental surfaces. Methods Selected inpatients were cultured weekly for S. aureus from stool, nares, skin (groin and axilla), and environmental surfaces (bed rail and bedside table). Investigator's hands were cultured after contacting the patients' skin and the environmental surfaces. Results Of 71 subjects, 32 (45.1%) had negative nares and stool cultures, 23 (32.4%) had positive nares and stool cultures, 13 (18.3%) were nares carriers only, and 3 (4.2%) were stool carriers only. Of the 39 patients with S. aureus carriage, 30 (76.9%) had methicillin-resistant isolates. In comparison to nares colonization only, nares and intestinal colonization was associated with increased frequency of positive skin cultures (41% versus 77%; p = 0.001) and trends toward increased environmental contamination (45% versus 62%; p = 0.188) and acquisition on investigator's hands (36% versus 60%; p = 0.057). Patients with negative nares and stool cultures had low frequency of S. aureus on skin and the environment (4.8% and 11.3%, respectively). Conclusion We found that hospitalized patients with S. aureus nares and/or stool carriage frequently had S. aureus on their skin and on nearby environmental surfaces. S. aureus intestinal colonization was associated with increased frequency of positive skin cultures, which could potentially facilitate staphylococcal infections and nosocomial transmission. more...

Abstract Background Contaminated environmental surfaces may play an important role in transmission of some healthcare-associated pathogens. In this study, we assessed the adequacy of cleaning practices in rooms of patients with Clostridium difficile-associated diarrhea (CDAD) and vancomycin-resistant Enterococcus (VRE) colonization or infection and examined whether an intervention would result in improved decontamination of surfaces. Methods During a 6-week period, we cultured commonly touched surfaces (i.e. bedrails, telephones, call buttons, door knobs, toilet seats, and bedside tables) in rooms of patients with CDAD and VRE colonization or infection before and after housekeeping cleaning, and again after disinfection with 10% bleach performed by the research staff. After the housekeeping staff received education and feedback, additional cultures were collected before and after housekeeping cleaning during a 10-week follow-up period. Results Of the 17 rooms of patients with VRE colonization or infection, 16 (94%) had one or more positive environmental cultures before cleaning versus 12 (71%) after housekeeping cleaning (p = 0.125), whereas none had positive cultures after bleach disinfection by the research staff (p < 0.001). Of the 9 rooms of patients with CDAD, 100% had positive cultures prior to cleaning versus 7 (78%) after housekeeping cleaning (p = 0.50), whereas only 1 (11%) had positive cultures after bleach disinfection by research staff (p = 0.031). After an educational intervention, rates of environmental contamination after housekeeping cleaning were significantly reduced. Conclusion Our findings provide additional evidence that simple educational interventions directed at housekeeping staff can result in improved decontamination of environmental surfaces. Such interventions should include efforts to monitor cleaning and disinfection practices and provide feedback to the housekeeping staff. more...

Background: Colonization and infection with vancomycin-resistant enterococci have been associated with exposure to antibiotics that are active against anaerobes. In mice that have intestinal colonization with vancomycin-resistant enterococci, these agents promote high-density colonization, whereas antibiotics with minimal antianaerobic activity do not.Methods: We conducted a seven-month prospective study of 51 patients who were colonized with vancomycin-resistant enterococci, as evidenced by the presence of the bacteria in stool. We examined the density of vancomycin-resistant enterococci in stool during and after therapy with antibiotic regimens and compared the effect on this density of antianaerobic agents and agents with minimal antianaerobic activity. In a subgroup of 10 patients, cultures of environmental specimens (e.g., from bedding and clothing) were obtained.Results: During treatment with 40 of 42 antianaerobic-antibiotic regimens (95 percent), high-density colonization with vancomycin-resistant enterococci was maintained (mean [+/-SD] number of organisms, 7.8+/-1.5 log per gram of stool). The density of colonization decreased after these regimens were discontinued. Among patients who had not received antianaerobic antibiotics for at least one week, 10 of 13 patients who began such regimens had an increase in the number of organisms of more than 1.0 log per gram (mean increase, 2.2 log per gram), whereas among 10 patients who began regimens of antibiotics with minimal antianaerobic activity, there was a mean decrease in the number of enterococci of 0.6 log per gram (P=0.006 for the difference between groups). When the density of vancomycin-resistant enterococci in stool was at least 4 log per gram, 10 of 12 sets of cultures of environmental specimens had at least one positive sample, as compared with 1 of 9 sets from patients with a mean number of organisms in stool of less than 4 log per gram (P=0.002).Conclusions: For patients with vancomycin-resistant enterococci in stool, treatment with antianaerobic antibiotics promotes high-density colonization. Limiting the use of such agents in these patients may help decrease the spread of vancomycin-resistant enterococci. [ABSTRACT FROM AUTHOR] more...

Brain-machine interface performance can be affected by neuroinflammatory responses due to blood-brain barrier (BBB) damage following intracortical microelectrode implantation. Recent findings suggest that certain gut bacterial constituents might enter the brain through damaged BBB. Therefore, we hypothesized that damage to the BBB caused by microelectrode implantation could facilitate microbiome entry into the brain. In our study, we found bacterial sequences, including gut-related ones, in the brains of mice with implanted microelectrodes. These sequences changed over time. Mice treated with antibiotics showed a reduced presence of these bacteria and had a different inflammatory response, which temporarily improved microelectrode recording performance. However, long-term antibiotic use worsened performance and disrupted neurodegenerative pathways. Many bacterial sequences found were not present in the gut or in unimplanted brains. Together, the current study established a paradigm-shifting mechanism that may contribute to chronic intracortical microelectrode recording performance and affect overall brain health following intracortical microelectrode implantation., Competing Interests: Competing interests: The contents do not represent the views of the U.S. Department of Veterans Affairs, the National Institutes of Health, or the United States Government. The authors declare no conflict of interest., (© 2025. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.) more...

We compare two initial specimen diversion devices evaluated over 3 months to investigate their utility in lowering blood culture contamination rates at or below 1%. Overall contamination rates during trial periods were 2.46% and 2.60% but usage was low, whereas device-specific contamination rates were 0.68% and 0.8%, respectively. more...

Brain-machine interface performance is largely affected by the neuroinflammatory responses resulting in large part from blood-brain barrier (BBB) damage following intracortical microelectrode implantation. Recent findings strongly suggest that certain gut bacterial constituents penetrate the BBB and are resident in various brain regions of rodents and humans, both in health and disease. Therefore, we hypothesized that damage to the BBB caused by microelectrode implantation could amplify dysregulation of the microbiome-gut-brain axis. Here, we report that bacteria, including those commonly found in the gut, enter the brain following intracortical microelectrode implantation in mice implanted with single-shank silicon microelectrodes. Systemic antibiotic treatment of mice implanted with microelectrodes to suppress bacteria resulted in differential expression of bacteria in the brain tissue and a reduced acute inflammatory response compared to untreated controls, correlating with temporary improvements in microelectrode recording performance. Long-term antibiotic treatment resulted in worsening microelectrode recording performance and dysregulation of neurodegenerative pathways. Fecal microbiome composition was similar between implanted mice and an implanted human, suggesting translational findings. However, a significant portion of invading bacteria was not resident in the brain or gut. Together, the current study established a paradigm-shifting mechanism that may contribute to chronic intracortical microelectrode recording performance and affect overall brain health following intracortical microelectrode implantation., Competing Interests: DECLARATION OF INTERESTS The authors declare no conflict of interest. more...

Background: Patients with measles can precipitate outbreaks in health care facilities where they seek care. Rural critical-access hospitals (CAHs) may be at higher risk of outbreaks given their size and potentially limited infection prevention resources., Methods: We surveyed CAHs in Idaho to ascertain their levels of preparedness for managing measles cases. A 25-item questionnaire was sent to infection preventionists at all 27 Idaho CAHs. The questionnaire covered organizational structure, resources for managing measles cases, and hospital policies for ensuring immunity among health care workers., Results: A total of 22 (82%) CAHs responded, reporting varying availability of facilities and resources for managing measles cases and disparate procedures for testing clinical samples and providing vaccines to nonimmune, exposed staff., Discussion: With measles incidence on the rise in the United States, our survey found that most of the responding hospitals had the basic organizational structure for facility-wide prevention and management efforts in case a patient with suspected or confirmed measles presented to that facility. Most of the hospitals also had at least some available resources to manage measles cases, as well as policies for ensuring immunity to measles among at least some groups of health care workers., Conclusions: This study provides initial perspectives on measles preparedness among Idaho CAHs, despite limited generalizability. Future studies should explore whether self-reported preparedness measures reflect the ability of the CAHs to control measles spread when cases present for care., (Copyright © 2019 Association for Professionals in Infection Control and Epidemiology, Inc. All rights reserved.) more...

Background: Clostridioides difficile infection (CDI) causes significant morbidity in nursing home residents. Our aim was to describe adherence to a bundled CDI prevention initiative, which had previously been deployed nationwide in Veterans Health Administration (VA) long-term care facilities (LTCFs), and to improve compliance with reinforcement., Methods: A multicenter pre- and post-reinforcement of the VA bundle consisting of environmental management, hand hygiene, and contact precautions was conducted in 6 VA LTCFs. A campaign to reinforce VA bundle components, as well as to promote select antimicrobial stewardship recommendations and contact precautions for 30 days, was employed. Hand hygiene, antimicrobial usage, and environmental contamination, before and after bundle reinforcement, were assessed., Results: All LTCFs reported following the guidelines for cleaning and contact precautions until diarrhea resolution pre-reinforcement. Environmental specimens rarely yielded C difficile pre- or post-reinforcement. Proper hand hygiene across all facilities did not change with reinforcement (pre 52.51%, post 52.18%), nor did antimicrobial use (pre 87-197 vs. post 84-245 antibiotic days per 1,000 resident-days). LTCFs found it challenging to maintain prolonged contact precautions., Discussion: Variation in infection prevention and antimicrobial prescribing practices across LTCFs were identified and lessons learned., Conclusions: Introducing bundled interventions in LTCFs is challenging, given the available resources, and may be more successful with fewer components and more intensive execution with feedback., (Published by Elsevier Inc.) more...

Background: Surgical site infection is a major postoperative complication after surgical procedures. The effectiveness of postoperative antimicrobial dressings in reducing surgical site infections is unclear and limited information is available on the efficacy of chlorhexidine gluconate (CHG)-impregnated postoperative dressings., Methods: A pilot study was conducted to examine the efficacy of an innovative CHG-impregnated postoperative dressing in reducing the burden of methicillin-resistant Staphylococcus aureus (MRSA) in an in vivo porcine, incisional-wound model. Sutured incisional wounds were contaminated with MRSA and then covered with a CHG wound dressing, a placebo control, or a nonantimicrobial gauze. The surviving MRSA population was quantitatively cultured 3 days postprocedure., Results: MRSA was not recovered from any of the 8 wounds that were treated with the CHG dressing (limit of detection, approximately 1.7 log 10 colony-forming units [cfu]/g tissue). In contrast, the average microbial recovery from wounds treated with the placebo dressing was 4.2 log 10 cfu/g and the average microbial recovery from wounds treated with the gauze dressing was 3.2 log 10 cfu/g., Conclusions: An innovative CHG dressing provided significant antimicrobial activity against MRSA contaminating a surgical wound in a porcine, incisional-wound model. Future clinical studies are needed to assess the efficacy of the CHG dressing to reduce the bacterial burden in postoperative wounds of surgical patients., (Copyright © 2019 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.) more...

Background: A 2015 study matching use of disposable and reusable sharps containers (DSCs, RSCs) with Clostridium difficile infection (CDI) incidence found a decreased incidence with DSCs. We conducted microbiologic samplings and examined the literature and disease-transmission principles to evaluate the scientific feasibility of such an association., Methods: (i) 197 RSCs were sampled for C. difficile at processing facilities; (ii) RSCs were challenged with high C. difficile densities to evaluate efficacy of automated decontamination; and (iii) 50 RSCs and 50 DSCs were sampled in CDI patient rooms in 7 hospitals. Results were coupled with epidemiologic studies, clinical requirements, and chain-of-infection principles, and tests of evidence of disease transmission were applied., Results: C. difficile spores were found on 9 of 197 (4.6%) RSCs prior to processing. Processing completely removed C. difficile. In CDI patient rooms, 4 of 50 RSCs (8.0%) and 8 of 50 DSCs (16.0%) had sub-infective counts of C. difficile (P = .27). DSCs were in permanent wall cabinets; RSCs were removed and decontaminated frequently., Conclusion: With C. difficile bioburden being sub-infective on both DSCs and RSCs, sharps containers being no-touch, and glove removal required after sharps disposal, we found 2 links in the chain of infection to be broken and 5 of 7 tests of evidence to be unmet. We conclude that sharps containers pose no risk of C. difficile transmission., (Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.) more...

Background: Clostridium difficile (CD) infection (CDI) increases patient morbidity, mortality and healthcare costs. Antibiotic treatment induces gut dysbiosis and is both a major risk factor for CD colonization and treatment of CDI. Probiotics have been trialed to support commensal gut microbiota and reduce CDI. This study investigated commensal microbe Faecalibacterium prausnitzii (FP) and a prebiotic, both known to yield butyrate and be anti-inflammatory and immunomodulatory, on CD colonization and gut integrity in mice., Methods: Mice were randomly grouped and supplemented daily with FP, prebiotic, FP + prebiotic, FP/prebiotic supernatant, or saline throughout the entire study. Following treatment with clindamycin for 3 days, mice were exposed to CD. Feces were collected at baseline, the day after antibiotic, and 1, 3, and 5 days after CD exposure and cultured for bacterial overgrowth and CD colonization. On days 1 and 5 after CD exposure, mice were randomly euthanized, and proximal colon was dissected for histological analysis and preparation of RNA for analysis of proinflammatory and anti-inflammatory cytokines., Results: Although all mice exhibited bacterial overgrowth and CD colonization, bacterial burden resolved quicker in the FP + prebiotic group. This was associated with induction and resolution of innate immune responses, anion exchanger, and tight junction protein preservation in proximal colon. CD toxin virulence potential was questionable as expression of CD toxin B receptor was depleted in the FP + prebiotic group., Conclusion: Supplementation with anti-inflammatory butyrate-supporting commensal bacteria and prebiotic may support innate immune responses and minimize bacterial burden and negative effects during antibiotic and CD exposure., (© 2018 American Society for Parenteral and Enteral Nutrition.) more...

Background: We hypothesized that the addition of a novel verbal electronic audio reminder to an educational patient hand hygiene bundle would increase performance of self-managed patient hand hygiene., Methods: We conducted a 2-group comparative effectiveness study randomly assigning participants to patient hand hygiene bundle 1 (n = 41), which included a video, a handout, and a personalized verbal electronic audio reminder (EAR) that prompted hand cleansing at 3 meal times, or patient hand hygiene bundle 2 (n = 34), which included the identical video and handout, but not the EAR. The primary outcome was alcohol-based hand sanitizer use based on weighing bottles of hand sanitizer., Results: Participants that received the EAR averaged significantly more use of hand sanitizer product over the 3 days of the study (mean ± SD, 29.97 ± 17.13 g) than participants with no EAR (mean ± SD, 10.88 ± 9.27 g; t 73  = 5.822; P ≤ .001)., Conclusions: The addition of a novel verbal EAR to a patient hand hygiene bundle resulted in a significant increase in patient hand hygiene performance. Our results suggest that simple audio technology can be used to improve patient self-management of hand hygiene. Future research is needed to determine if the technology can be used to promote other healthy behaviors, reduce infections, and improve patient-centered care without increasing the workload of health care workers., (Published by Elsevier Inc.) more...

Health care-associated methicillin-resistant Staphylococcus aureus (MRSA) infections are a burden on the health care system. Clinical laboratories play a key role in reducing this burden, as the timely identification of MRSA colonization or infection facilitates infection control practices that are effective at limiting invasive MRSA infections. The Xpert MRSA NxG assay recently received FDA clearance for the direct detection of MRSA from nasal swabs. This multicenter study evaluated the clinical performance characteristics of the Xpert MRSA NxG assay with prospectively collected rayon nasal swabs ( n = 1,103) and flocked swab (ESwab) nasal specimens ( n = 846). Culture-based identification methods and antimicrobial susceptibility testing were used as the reference standards for comparison. According to the reference method, the positivity rates for MRSA in the population evaluated were 11.1% (122/1,103) for rayon swabs and 11.6% (98/846) for flocked swabs. The overall sensitivity and specificity of the rayon swabs were 91.0% (95% confidence interval [CI], 84.6 to 94.9%) and 96.9% (95% CI, 95.7 to 97.8%), respectively, across eight testing sites. The flocked swab specimens were 92.9% sensitive (95% CI, 86.0 to 96.5%) and 97.6% specific (95% CI, 96.2 to 98.5%) for MRSA detection across six testing sites. The sensitivity and specificity of the combined flocked and rayon swab data were 91.8% (95% CI, 87.4 to 94.8%) and 97.2% (95% CI, 96.3 to 97.9%), respectively. The positive predictive value (PPV) for rayon swabs was 78.7%, versus 83.5% for ESwabs. The negative predictive values (NPVs) for rayon swabs and ESwab specimens were 98.9% and 99.1%, respectively. In conclusion, the Xpert MRSA NxG assay is a sensitive and specific assay for the direct detection of MRSA from nasal swab specimens., (Copyright © 2017 American Society for Microbiology.) more...

We know that within the complex mammalian gut is any number of metabolic biomes. The gut has been sometimes called the "second brain" within the "gut-brain axis". A more informative term would be the gut-brain metabolic interactome, which is coined here to underscore the relationship between the digestive system and cognitive function or dysfunction as the case may be. Co-metabolism between the host and the intestinal microbiota is essential for life's processes. How diet, lifestyle, antibiotics and other factors shape the gut microbiome constitutes a rapidly growing area of research. Conversely, the gut microbiome also affects mammalian systems. Metabolites of the gut-brain axis are potential targets for treatment and drug design since the interaction or biochemical interplay results in net metabolite production or end-products with either positive or negative effects on human health. This review explores the gut-brain metabolic interactome, with particular emphasis on drug design and treatment strategies and how commensal bacteria or their disruption lead to dysbiosis and the effect this has on neurochemistry. Increasing data indicate that the intestinal microbiome can affect neurobiology, from mental and even behavioral health to memory, depression, mood, anxiety, obesity, cravings and even the creation and maintenance of the blood brain barrier. more...

This white paper identifies knowledge gaps and new challenges in healthcare epidemiology research, assesses the progress made toward addressing research priorities, provides the Society for Healthcare Epidemiology of America (SHEA) Research Committee's recommendations for high-priority research topics, and proposes a road map for making progress toward these goals. It updates the 2010 SHEA Research Committee document, "Charting the Course for the Future of Science in Healthcare Epidemiology: Results of a Survey of the Membership of SHEA," which called for a national approach to healthcare-associated infections (HAIs) and a prioritized research agenda. This paper highlights recent studies that have advanced our understanding of HAIs, the establishment of the SHEA Research Network as a collaborative infrastructure to address research questions, prevention initiatives at state and national levels, changes in reporting and payment requirements, and new patterns in antimicrobial resistance. more...

Asymptomatic carriage of Clostridium difficile is common in hospitals, but the risk for transmission by carriers is unclear. In this point prevalence culture survey of asymptomatic hospitalized patients, 18 of 149 (12%) were carriers of toxigenic C. difficile. By comparison with C. difficile infection (CDI) patients, the prevalence of skin and/or environmental contamination was significantly lower in asymptomatic carriers (3/18, 17% versus 5/6, 83%; P = 0.007), but carriers outnumbered CDI patients in the hospital by a factor of 3 to 1. These data suggest that asymptomatic carriers have the potential to contribute to C. difficile transmission in hospitals., (Published by Elsevier Ltd.) more...

Contaminated environmental surfaces are an important source for transmission of Clostridium difficile. However, there are no efficient and easy methods to assess contamination. The performance of a commercial real-time polymerase chain reaction (PCR) assay was evaluated for detection of environmental toxigenic C. difficile in comparison with anaerobic culture followed by toxin testing of isolates. For 66 sites sampled, PCR had a sensitivity of 17.39%, specificity 100%, positive predictive value 100% and negative predictive value 69.35%. Increasing the PCR cycle threshold (CT) value to 45 increased sensitivity to 52% without decreasing specificity. The commercial PCR assay is not sufficiently sensitive for environmental monitoring, but improved sensitivity might be possible through CT value modification., (© 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.) more...

Background: The efficacy of probiotics for the prevention of Clostridium difficile infection (CDI) is highly controversial, particularly with regard to the prevention of recurrent CDI. We hypothesize that primary prevention of CDI among patients receiving antibiotics might be a more achievable goal for probiotics than prevention in patients with previous CDI where the host flora is markedly altered., Methods: We conducted a literature search for randomized, placebo-controlled efficacy studies of probiotic use among adults receiving antibiotics, in which CDI was one of the outcomes measured. In addition, we conducted meta-analyses of probiotics that were included in more than one randomized trial., Results: Eleven studies were identified; most were seriously underpowered to determine the efficacy of probiotics in the prevention of CDI. Two showed significantly lower rates of CDI among the probiotic recipients. A meta-analysis of three studies that used the probiotic combination Lactobacillus acidophilus CL1285 and Lactobacillus casei LBC80R and a combined analysis of those studies with four studies that used Saccharomyces boulardii, showed lower CDI rates in recipients of probiotics compared with recipients of placebo (risk ratio=0.39; 95% confidence interval 0.19-0.79)., Conclusions: While potential flaws in study design were identified, a review of the available literature suggests that the primary prevention of CDI with specific probiotic agents may be achievable. Additional studies of sufficient size and with rigorous design are needed to confirm these findings., (Published by Elsevier Ltd.) more...

Background: Probiotics appear to be beneficial in inflammatory bowel disease, but their mechanism of action is incompletely understood. We investigated whether probiotic-derived sphingomyelinase mediates this beneficial effect., Methodology/principal Findings: Neutral sphingomyelinase (NSMase) activity was measured in sonicates of the probiotic L. brevis (LB) and S. thermophilus (ST) and the non-probiotic E. coli (EC) and E. faecalis (EF). Lamina propria mononuclear cells (LPMC) were obtained from patients with Crohn's disease (CD) and Ulcerative Colitis (UC), and peripheral blood mononuclear cells (PBMC) from healthy volunteers, analysing LPMC and PBMC apoptosis susceptibility, reactive oxygen species (ROS) generation and JNK activation. In some experiments, sonicates were preincubated with GSH or GW4869, a specific NSMase inhibitor. NSMase activity of LB and ST was 10-fold that of EC and EF sonicates. LB and ST sonicates induced significantly more apoptosis of CD and UC than control LPMC, whereas EC and EF sonicates failed to induce apoptosis. Pre-stimulation with anti-CD3/CD28 induced a significant and time-dependent increase in LB-induced apoptosis of LPMC and PBMC. Exposure to LB sonicates resulted in JNK activation and ROS production by LPMC. NSMase activity of LB sonicates was completely abrogated by GW4869, causing a dose-dependent reduction of LB-induced apoptosis. LB and ST selectively induced immune cell apoptosis, an effect dependent on the degree of cell activation and mediated by bacterial NSMase., Conclusions: These results suggest that induction of immune cell apoptosis is a mechanism of action of some probiotics, and that NSMase-mediated ceramide generation contributes to the therapeutic effects of probiotics. more...