Prevalence, risk factors, and characterisation of extended-spectrum ß-lactamase -producing Enterobacterales (ESBL-E) in horses entering an equine hospital and description of longitudinal excretion.

BACKGROUND: Extended-spectrum ß-lactamase -producing Enterobacterales (ESBL-E) are important zoonotic pathogens that can cause serious clinical infections, also in horses. Preventing the spread of ESBL-E, especially in the equine hospital environment, is key to reducing the number of difficult-to-treat infections. Estimating the local prevalence of ESBL-E in horses is crucial to establish targeted infection control programs at equine hospitals. We conducted a prevalence and risk factor study in equine patients on admission to an equine teaching hospital in Finland through a rectal ESBL-E screening specimen of the horse and a questionnaire. RESULTS: The prevalence of ESBL-E in admitted horses was 3% (5/161, 95% CI 1-7%); none of the tested factors remained statistically significant in multivariate analysis, although antimicrobial treatment within three months was borderline significant (p = 0.052). Extended-spectrum ß-lactamase -producing Klebsiella pneumoniae ST6179:CTX-M-15 was detected in three horses using whole-genome sequencing, which in combination with patient records suggested nosocomial transmission. Escherichia coli isolates were ST1250:CTX-M-1 (n = 1), ST1079:CTX-M-1 (n = 1), and ST1245:CTX-M-14 (n = 1). Multiple virulence genes were detected in the ESBL-E isolates. In the ESBL-E positive horses enrolled in a one-year follow-up study, ESBL-E were unlikely to be isolated in rectal screening specimens after the initial positive specimen. CONCLUSIONS: The prevalence of ESBL-E in horses visiting a veterinary teaching hospital in Finland is low, indicating an overall low prevalence estimate in the country's equine population. No statistically significant risk factors were identified, likely due to the low number of cases. The duration of ESBL-E carriage is likely to be very short in horses.

Microbiology of catheter associated bloodstream infection: differences according to catheter type.

OBJECTIVES: Catheter-associated bloodstream infections (CABSI) cause preventable morbidity. We compared the microbiological aetiology of CABSI across different types of central and peripherally inserted catheters. METHODS: We analysed prospectively collected CABSI data in a 2100-bed hospital network in Switzerland between 2016 and 2022. We included: short-term non-tunnelled central venous catheters (CVC); long-term catheters (tunnelled, or peripherally inserted central catheters); arterial catheters; dialysis catheters; and peripheral venous catheters (PVC). We used multivariable logistic regression models to describe risk of Staphylococcus aureus and Gram-negative pathogens according to catheter type. RESULTS: 416 CABSI episodes were included, including 60 episodes of S. aureus and 92 episodes of Gram-negative CABSI. Microbiological profile differed between catheter types. Together, PVC and dialysis catheters accounted for 43/60 (72%) of all S. aureus CABSI. After adjusting for age, sex and haematology/oncology care, odds of S. aureus were higher for haemodialysis catheters (OR 17.3, 95% CI 5.75-52.2, p <0.01) and PVC (OR 2.96, 95% CI 1.22-7.20, p=0.02) compared to short-term non-tunnelled CVC. Odds of Gram-negative organism as cause of CABSI were higher in long-term catheters versus short-term non-tunnelled CVC (OR 2.70, 95% CI 1.37-5.24). CONCLUSIONS: CABSI in catheters other than short-term non-tunnelled CVC are more commonly caused by virulent organisms including S. aureus and Gram-negative bacteria. Catheter type should be considered when selecting empirical antimicrobial therapies.

Reduction of hemodialysis catheter-related blood stream infections in intensive care units after systematic use of taurolidine-citrate-heparin locking solution.

INTRODUCTION: Dialysis catheter-associated bacteremia in Intensive Care Units (ICUs) increases morbidity and mortality, prolongs hospital admission and increases admission costs. Taurolidine-Citrate-Heparin Locking Solution (TCHLS) is a catheter-locking solution with a broad antimicrobial activity against gram-positive and gram-negative bacteria and fungi. The aim of this study was to analyze the effect of systematic sealing of hemodialysis catheters in the ICUs of the Hospital Clínic de Barcelona on the incidence of hemodialysis catheter-related blood stream infections (CRBSI). MATERIAL AND METHODS: CRBSI episodes of patients who underwent intermittent hemodialysis (IHD) during ICU admission were reviewed. TCHLS was established as a routine dialysis catheter sealing solution in the hospital ICUs in 2015. As a control group an historic pre-TCHLS group from 2010 to 2014 was used. The post-TCHLS period comprised from 2015 to 2018. RESULTS: A total of 243 and 266 patients required IHD in the pre- and post TCHLS periods, respectively. The number of CRBSI in the pre-TCHLS period was 18 (7.43%) as compared to 9 (3.38%) in the post-TCHLS period (p = 0.043). All infections were from percutaneous catheters except for three catheters that were tunneled. There was no association between the location of the catheter and the incidence of CRBSI. The most frequent isolated microorganisms were Gram positive bacteria (48.38%), with a global predominance of Staphylococcus epidermidis (32.25%). There were no significant differences in the median days from the start of hemodialysis to the onset of bacteremia (23.5 days in pre-TCHLS group vs 21 days in the post-TCHLS). There were also no significant differences between the days of ICU stay in the CRBSI in both groups or in mortality, being the overall mortality of 65.9%. CONCLUSIONS: In our population, the systematic application of TCHLS in the sealing of dialysis catheters in critically ill patients reduces the incidence of CRBSI in ICUs.

Materials-based incidence of urinary catheter associated urinary tract infections and the causative micro-organisms: systematic review and meta-analysis.

BACKGROUND: Both long (> 30 days) and short-term (≤ 30 days) catheterisation has been associated with urinary tract infections (UTIs) due to the invasive nature of device insertion through the urethra. Catheter associated Urinary Tract Infections (CAUTIs) are common (prevalence of ~ 8.5%) infections which can be treated with antibiotics; however, CAUTIs are both expensive to treat and contributes to the antibiotic usage crisis. As catheters are unlikely be replaced for the management of patients' urination, ways of reducing CAUTIs are sought out, using the catheter device itself. The aim of this review is to assess the incidence of CAUTI and the causative micro-organisms when different urinary catheter devices have been used by humans, as reported in published research articles. METHODS: A Systematic Literature Review was conducted in Ovid Medline, Web of Science and PubMed, to identify studies which investigated the incidence of UTI and the causative micro-organisms, in patients with different urinary catheter devices. The articles were selected based on a strict set of inclusion and exclusion criteria. The data regarding UTI incidence was extracted and calculated odds ratio were compared across studies and pooled when types of catheters were compared. CAUTI causative micro-organisms, if stated within the research pieces, were also gathered. RESULTS: A total of 890 articles were identified, but only 26 unique articles met the inclusion/exclusion criteria for this review. Amongst the large cohort there were catheters of materials silicone, latex and PVC and catheter modifications of silver nanoparticles and nitrofurantoin antibiotics. The meta-analysis did not provide a clear choice towards a single catheter against another although silver-based catheters, and silver alloy, appeared to statistically reduce the OR of developing CAUTIs. At genus level the three commonest bacteria identified across the cohort were E. coli, Enterococcus spp. and Pseudomonas spp. whilst considering only at the genus level, with E. coli, Klebsiella pneumonia and Enterococcus faecalis most common at the species-specific level. CONCLUSIONS: There does not appear to be a catheter type, which can significantly reduce the incidence of CAUTI's in patients requiring catheterisation. Ultimately, this warrants further research to identify and develop a catheter device material that will reduce the incidence for CAUTIs.

Synthesis of the pyruvic acid acetal containing tetrasaccharide repeating unit corresponding to the K82 capsular polysaccharide of Acinetobacter baumannii LUH5534 strain.

An efficient synthetic strategy has been developed to achieve a pyruvic acid acetal containing tetrasaccharide repeating unit corresponding to the K82 capsular polysaccharide of Acinetobacter baumannii LUH5534 strain in very good yield. The synthetic scheme involves the use of suitably functionalized monosaccharide thioglycosides as glycosyl donors and a combination of N-iodosuccinimide (NIS) and trimethylsilyl trifluoromethanesulfonate (TMSOTf) as thiophilic glycosylation activator to furnish satisfactory yield of the products with appropriate stereochemistry at the glycosidic linkages. Incorporation of the (R)-pyruvic acid acetal in the d-galactose moiety was achieved in very good yield by the treatment of the diol derivative with methyl 2,2-bis(p-methylphenylthio)propionate in the presence of a combination of NIS and triflic acid.

Development and validation of prediction models for nosocomial infection and prognosis in hospitalized patients with cirrhosis.

BACKGROUND: Nosocomial infections (NIs) frequently occur and adversely impact prognosis for hospitalized patients with cirrhosis. This study aims to develop and validate two machine learning models for NIs and in-hospital mortality risk prediction. METHODS: The Prediction of Nosocomial Infection and Prognosis in Cirrhotic patients (PIPC) study included hospitalized patients with cirrhosis at the Qingchun Campus of the First Affiliated Hospital of Zhejiang University. We then assessed several machine learning algorithms to construct predictive models for NIs and prognosis. We validated the best-performing models with bootstrapping techniques and an external validation dataset. The accuracy of the predictions was evaluated through sensitivity, specificity, predictive values, and likelihood ratios, while predictive robustness was examined through subgroup analyses and comparisons between models. RESULTS: We enrolled 1,297 patients into derivation cohort and 496 patients into external validation cohort. Among the six algorithms assessed, the Random Forest algorithm performed best. For NIs, the PIPC-NI model achieved an area under the curve (AUC) of 0.784 (95% confidence interval [CI] 0.741-0.826), a sensitivity of 0.712, and a specificity of 0.702. For in-hospital mortality, the PIPC- mortality model achieved an AUC of 0.793 (95% CI 0.749-0.836), a sensitivity of 0.769, and a specificity of 0.701. Moreover, our PIPC models demonstrated superior predictive performance compared to the existing MELD, MELD-Na, and Child-Pugh scores. CONCLUSIONS: The PIPC models showed good predictive power and may facilitate healthcare providers in easily assessing the risk of NIs and prognosis among hospitalized patients with cirrhosis.

A questionnaire survey of infection control measures during the coronavirus infectious disease 2019 pandemic era.

OBJECTIVE: To clarify the infection control measures required in the event of a new infectious disease outbreak, we conducted a questionnaire survey on the infection control measures implemented against coronavirus disease 2019 (COVID-19). METHODS: An invitation to participate in this survey was sent to the heads of 2689 facilities affiliated with the members of the Japanese Society for Infection Prevention and Control in February 2023, requesting responses to the online survey using Google Forms by March 2023. RESULTS: Six hundred and forty-five facilities, including 20 clinics and 625 hospitals, participated in the survey. This survey revealed that various infection control measures were implemented, including universal masking in the non-COVID-19 ward (96.5 %), screening tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on scheduled admission (89.0 %), SARS-CoV-2 tests (98.7 %), and isolation in private rooms (76.5 %) for inpatients with fever. However, nosocomial infections and clusters of COVID-19 occurred in 94.4 % and 90.9 % of cases during the investigation period, respectively. One of the reasons for these results is that healthcare personnel (HCP) and patients were common index cases of nosocomial infections, and the most common cause of clusters was the work of symptomatic HCPs. These results suggest that HCPs should understand that they can be index cases or spreaders. On the other hand, the most common support from external facilities was healthcare centers, followed by physicians or nurses from other hospitals. CONCLUSION: In response to the emergence of infections, it is important to consider implementing infection control measures for HCPs and patients.

Exceptions to the rule: When does resistance evolution not undermine antibiotic therapy in human bacterial infections?

The use of antibiotics to treat bacterial infections often imposes strong selection for antibiotic resistance. However, the prevalence of antibiotic resistance varies greatly across different combinations of pathogens and drugs. What underlies this variation? Systematic reviews, meta-analyses, and literature surveys capable of integrating data across many studies have tried to answer this question, but the vast majority of these studies have focused only on cases where resistance is common or problematic. Yet much could presumably be learned from the cases where resistance is infrequent or absent. Here we conducted a literature survey and a systematic review to study the evolution of antibiotic resistance across a wide range of pathogen-by-drug combinations (57 pathogens and 53 antibiotics from 15 drug classes). Using Akaike information criterion-based model selection and model-averaged parameter estimation we explored 14 different factors posited to be associated with resistance evolution. We find that the most robust predictors of high resistance are nosocomial transmission (i.e., hospital-acquired pathogens) and indirect transmission (e.g., vector-, water-, air-, or vehicle-borne pathogens). While the former was to be expected based on prior studies, the positive correlation between high resistance frequencies and indirect transmission is, to our knowledge, a novel insight. The most robust predictor of low resistance is zoonosis from wild animal reservoirs. We also found partial support that resistance was associated with pathogen type, horizontal gene transfer, commensalism, and human-to-human transmission. We did not find support for correlations between resistance and environmental reservoirs, mechanisms of drug action, and global drug use. This work explores the relative explanatory power of various pathogen and drug factors on resistance evolution, which is necessary to identify priority targets of stewardship efforts to slow the spread of drug-resistant pathogens.

Healthcare-associated infections and antimicrobial resistance in Canadian acute care hospitals, 2018-2022.

Background: Healthcare-associated infections (HAIs) and antimicrobial resistance (AMR) continue to contribute to excess morbidity and mortality among Canadians. Objective: This report describes epidemiologic and laboratory characteristics and trends of HAIs and AMR from 2018 to 2022 (Candida auris, 2012-2022) using surveillance and laboratory data submitted by hospitals to the Canadian Nosocomial Infection Surveillance Program (CNISP) and by provincial and territorial laboratories to the National Microbiology Laboratory. Methods: Data collected from 88 Canadian sentinel acute care hospitals between January 1, 2018, and December 31, 2022, for Clostridioides difficile infections (CDIs), carbapenemase-producing Enterobacterales (CPE) infections, methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs) and vancomycin-resistant Enterococcus (VRE) BSIs. Candida auris (C. auris) surveillance was initiated in 2019 by CNISP and in 2017 (retrospectively to 2012) by the National Microbiology Laboratory. Trend analysis for case counts, rates, outcomes, molecular characterization and AMR profiles are presented. Results: From 2018 to 2022, decreased rates per 10,000 patient days were observed for CDIs (7% decrease; 5.42-5.02) and MRSA BSIs (2.9% decrease; 1.04-1.01). Infection rates for VRE BSIs increased by 5.9% (0.34-0.36). Infection rates for CPE remained low but increased by 133% (0.06-0.14). Forty-three C. auris isolates were identified in Canada from 2012 to 2022, with the majority in Western and Central Canada (98%). Conclusion: From 2018 to 2022, the incidence of MRSA BSIs and CDIs decreased and VRE BSI and CPE infections increased in the Canadian acute care hospitals participating in a national sentinel network (CNISP). Few C. auris isolates were identified from 2012 to 2022. Reporting standardized surveillance data to inform the application of infection prevention and control practices in acute care hospitals is critical to help decrease the burden of HAIs and AMR in Canada.

[Recommendations for the prevention of healthcare-associated infections in nursing homes]. / Guía de recomendaciones para la prevención de la infección sociosanitaria en las residencias de mayores.

Nursing homes (NH) although conceptually they should look as much like a home as possible, NH have unquestionable similarities with a nosocomium as they are places where many patients with underlying diseases and comorbidities accumulate and where the transmission of microorganisms between residents and between residents and caregivers is frequent.We have not found any recommendations specifically aimed at the prevention of nosocomial infections in MRI by the major Public Health Agencies and, therefore, the Health Sciences Foundation (Fundación de Ciencias de la Salud) has convened a series of experts and 14 Spanish scientific societies to discuss recommendations that could guide NH personnel in establishing written programs for the control and reduction of these infections. The present document is the result of these deliberations and contains suggestions for establishing such control programs on a voluntary and flexible basis in NH. We also hope that the document can help the health authorities to encourage this control activity in the different territorial areas of Spain. In our opinion, it is necessary to draw up a written plan and establish the figure of a coordinator or person responsible for implementing these projects. The document includes measures to be implemented and ways of quantifying the reality of different problems and of monitoring the impact of the measures established.

[On the issues of additional public support of workers involved in medical care support during period of COVID-19].

The article considers issues of organizational and legal progress of social protection of workers involved in medical care during period of COVID-19. The purpose of the study is to analyze regulatory legal documents that define state guarantees that provide social protection for persons involved in the provision of medical care during COVID-19. The attempt was made to analyze international and national information on relevant morbidity, mortality and disability of health care workers, but respective data was not readily available in open admission. The analysis of international documents (the WHO, CDC, JHU reports), public documents of the Russian Federation, information from official websites of the President of the Russian Federation and the executive authorities of the Russian Federation (state reports on sanitary and epidemiological well-being of the population in the Russian Federation in 2020-2022) demonstrated the following. The whole world faced with the problem of protecting health care workers from contamination with new corona-virus infection. In the Russian Federation, unprecedented measures were taken to ensure social protection for this category of workers, including provision of additional social benefits.

Controlled Substance Liquid Waste Management Systems As Potential Reservoirs for Nosocomial Infection in a Pediatric Hospital.

OBJECTIVE: The purpose of this study was to determine if controlled substance waste management systems (CSWMS) demonstrate microbial growth, and therefore present a potential infection risk to pediatric hospital patients. METHODS: Twenty CSWMS, either Smart Sink or Pharma Lock systems, located in patient care areas were sampled. Twelve were located in critical care areas. Cultures were obtained by swabbing the drain grate with a sterile swab. Swabs were then transported to the microbiology lab for culture. Each sample was labeled with the location of the CSWMS and each system was photographed. RESULTS: Of the CSWMS sampled, 50% demonstrated bacterial or fungal growth with a total of 15 microorganisms isolated, including 3 systems with Micrococcus luteus, 2 with Aspergillus species, and 2 with -Bacillus cereus. Nine of the 15 microorganisms isolated were from systems in the pediatric intensive care unit (PICU) followed by 2 microorganisms in the neonatal intensive care unit (NICU). Of the 12 systems sampled in critical care areas, 8 (66%) had positive cultures. Of the 10 systems which demonstrated growth, 9 were Pharma Lock and 1 was Smart Sink. CONCLUSION: Controlled substance waste management systems harbor potential pathogens and may serve as reservoirs of infectious agents in pediatric hospitals. Microbial growth was identified in more than half of sampled CSWMS located in critical care areas, where the most vulnerable patients are located. Based on this study, a cleaning procedure for CSWMS should be implemented. Further investigation on the relationship between CSWMS and nosocomial infections is warranted.

The nosocomial infection survey among patients suffering from the Coronavirus disease-2019 hospitalized in Ayatollah Rouhani Hospital, Babol.

Background: Having a weakened immune system can make patients easily get nosocomial infection (NI) with multi-drug resistant (MDR) bacteria and put them in a dangerous situation. It causes long hospital stays, disability, economic burden, and even death. The present study aimed to determine the prevalence of NI in patients suffering from COVID-19. Methods: In this retrospective study, the information on 250 patients suffering from COVID-19 in the intensive care unit (ICU) (2020 to 2021) was considered. For statistical analysis, analysis of variance (ANOVA), paired samples t-test, and chi-square using SPSS-23 software were used (p<0.05). Results: Two hundred and fifty hospitalized (107 females and 143 males, mean ± standard deviation (SD) of age; 56.50 ± 17.20) patients were considered. The most (97.60%) medicine prescribed was remdesivir. Candida spp. (two females), Escherichia coli (two females), Acinetobacter spp. (one female), Citrobacter spp. (one female), Pseudomonas spp. (one male), Sphingomonas spp. (one male), Stenotrophomonas spp. (one male) and Enterobacter spp. (one male) were isolated from the patient's specimens. Four of seven bacterial isolates were positive for MDR. NI was diagnosed in six patients. There was no significant relationship between the age with the isolated microbes (P=0.154) and MDR (P=0.987) and also between gender with common microbes (P=0.576) and MDR (P=0.143). Conclusion: The coexistence of bacteria and NI was observed in patients. Remdesivir was prescribed for most patients. Most bacteria were resistant to antibiotics, especially, ß-lactams.

Surgical Site Infections in Gastrointestinal Surgeries: Estimation of Prevalence, Risk Factors and Bacteriological Profile.

INTRODUCTION: Surgical site infections (SSIs) are one of the leading causes of operation-related adverse effects. To create an effective hospital infection program, information about a local pattern is essential. The ever-changing pattern of infections and inappropriate use of antibiotics has predisposed to the development of drug-resistant strains and has made the management of SSIs arduous. AIMS AND OBJECTIVES: The purpose of this study is to estimate prevalence and identify risk factors and commonest organisms associated with SSIs. METHODOLOGY: In this analytical cross-sectional study, the relationship between various risk factors and the development of SSIs was evaluated in patients undergoing elective surgery and staying at least seven days postoperatively in the Department of Surgical Gastroenterology and Liver transplant for a study duration of two months. Diagnosis of SSIs was based on modified CDC criteria. Wound pus was followed by blood collection in suspected secondary septicemia. MacConkey and blood agar were used to culture pus; brain heart infusion broth was used for blood samples. Antimicrobial susceptibility testing was carried out using Mueller-Hinton agar by the Kirby-Bauer method. RESULTS:  Twelve out of 50 had developed postsurgical wound infections where Gram-negative organisms prevailed over Gram-positive ones. The associated risk factors identified in this study are age, BMI, wound class, American Society of Anesthesiologists (ASA) score, preprocedural WBC count >10,000, and the duration of surgery. Escherichia coli is the causative microbe for the majority of infections (35.7%). Gram-negative bacteria isolated in this study were extended-spectrum ß-lactamase (ESBL) producers. Multidrug-resistant organisms were predominant.  Conclusion: The present study identified an SSI rate of 24% in gastrointestinal surgeries. The sensitivity and resistance pattern of the organisms isolated will help in measures to be taken to devise a proper and effective current hospital antibiotic prophylaxis policy.

Persistent enrichment of multidrug-resistant Klebsiella in oral and nasal communities during long-term starvation.

BACKGROUND: The human oral and nasal cavities can act as reservoirs for opportunistic pathogens capable of causing acute infection. These microbes asymptomatically colonize the human oral and nasal cavities which facilitates transmission within human populations via the environment, and they routinely possess clinically significant antibiotic resistance genes. Among these opportunistic pathogens, the Klebsiella genus stands out as a notable example, with its members frequently linked to nosocomial infections and multidrug resistance. As with many colonizing opportunistic pathogens, the essential transmission factors influencing the spread of Klebsiella species among both healthy and diseased individuals remain unclear. RESULTS: Here, we explored a possible explanation by investigating the ability of oral and nasal Klebsiella species to outcompete their native microbial community members under in vitro starvation conditions, which could be analogous to external hospital environments or the microenvironment of mechanical ventilators. When K. pneumoniae and K. aerogenes were present within a healthy human oral or nasal sample, the bacterial community composition shifted dramatically under starvation conditions and typically became enriched in Klebsiella species. Furthermore, introducing K. pneumoniae exogenously into a native microbial community lacking K. pneumoniae, even at low inoculum, led to repeated enrichment under starvation. Precise monitoring of K. pneumoniae within these communities undergoing starvation indicated rapid initial growth and prolonged viability compared to other members of the microbiome. K. pneumoniae strains isolated from healthy individuals' oral and nasal cavities also exhibited resistance to multiple classes of antibiotics and were genetically similar to clinical and gut isolates. In addition, we found that in the absence of Klebsiella species, other understudied opportunistic pathogens, such as Peptostreptococcus, increased in relative abundance under starvation conditions. CONCLUSIONS: Our findings establish an environmental and microbiome community circumstance that allows for the enrichment of Klebsiella species and other opportunistic pathogens. Klebsiella's enrichment may hinge on its ability to quickly outgrow other members of the microbiome. The ability to outcompete other commensal bacteria and to persist under harsh environmental conditions could be an important factor that contributes to enhanced transmission in both commensal and pathogenic contexts. Video Abstract.

Staphylococcus aureus associated with surgical site infections in Western Kenya reveals genomic hotspots for pathogen evolution.

Objectives. Staphylococcus aureus is one of the most common pathogens attributed to hospital infections. Although S. aureus infections have been well studied in developed countries, far less is known about the biology of the pathogen in sub-Saharan Africa. Methods. Here, we report on the isolation, antibiotic resistance profiling, whole genome sequencing, and genome comparison of six multi-drug resistant isolates of S. aureus obtained from a referral hospital in Kakamega, Western Kenya. Results. Five of the six isolates contained a 20.7 kb circular plasmid carrying blaZ (associated with resistance to ß-lactam antibiotics). These five strains all belonged to the same sequence type, ST152. Despite the similarity of the plasmid in these isolates, whole genome sequencing revealed that the strains differed, depending on whether they were associated with hospital-acquired or community-acquired infections. Conclusion. The intriguing finding is that the hospital-acquired and the community-acquired isolates of S. aureus belonging to the same genotype, ST152, formed two separate sub-clusters in the phylogenetic tree and differed by the repertoire of accessory virulence genes. These data suggest ongoing adaptive evolution and significant genomic plasticity.

Analyzing Pre-operative Hospital Stay and Incidence of Hospital Acquired Infection: A Retrospective Study.

Background and objectives: Healthcare-associated infections (HCAIs) pose a significant challenge, impacting patient safety and treatment effectiveness. This retrospective study investigates the correlation between pre-operative hospital stays and HCAIs in ICU cardiac surgery patients. Materials and methods: Medical records of 35 patients who died post-cardiac surgery in the ICU were analyzed, focusing on the duration of pre-operative hospitalization. Results: Prolonged pre-operative stays strongly correlate (r = 0.993) with increased HCAIs, indicating a critical risk factor. Conclusions: The duration of pre-operative hospital stays is pivotal in HCAI risk. Prospective multicenter studies are needed for validation, which is crucial for enhancing patient safety and treatment efficacy.

Evaluation of chlorogenic acid and carnosol for anti-efflux pump and anti-biofilm activities against extensively drug-resistant strains of Staphylococcus aureus and Pseudomonas aeruginosa.

Efflux pumps and biofilm play significant roles in bacterial antibiotic resistance. This study investigates the potential of chlorogenic acid (CGA) and carnosol (CL), as phenolic and diterpene compounds, respectively, for their inhibitory effects on efflux pumps. Among the 12 multidrug-resistant (MDR) strains of Staphylococcus aureus and Pseudomonas aeruginosa isolated from nosocomial skin infections, eight strains were identified as extensively drug resistant (XDR) using the disc diffusion method. The presence of efflux pumps in MDR strains of S. aureus and P. aeruginosa was screened using carbonyl cyanide-m-chlorophenylhydrazone. Between the 12 MDR strains of S. aureus and P. aeruginosa, 80% (4 out of 5) of the S. aureus strains and 85.7% (6 out of 7) of the P. aeruginosa strains exhibited active efflux pumps associated with gentamicin resistance. The checkerboard assay results, in combination with gentamicin, demonstrated that CGA exhibited a reduction in the minimum inhibitory concentration (MIC) for XDR S. aureus strain. Similarly, CL showed a synergistic effect and reduced the MIC for both XDR strains of S. aureus and P. aeruginosa. Flow cytometry was used to examine efflux pump activity at sub-MIC concentrations of 1/8, 1/4, and 1/2 MIC in comparison to the control. In XDR S. aureus, CGA demonstrated 39%, 70%, and 19% inhibition, while CL exhibited 74%, 73.5%, and 62% suppression. In XDR P. aeruginosa, CL exhibited inhibition rates of 25%, 10%, and 15%. The inhibition of biofilm formation was assessed using the microtiter plate method, resulting in successful inhibition of biofilm formation. Finally, the MTT assay was conducted, and it confirmed minimal cytotoxicity. Given the significant reduction in efflux pump activity and biofilm formation observed with CGA and CL in this study, these compounds can be considered as potential inhibitors of efflux pumps and biofilm formation, offering potential strategies to overcome antimicrobial resistance. IMPORTANCE: In summary, CGA and CL demonstrated promising potentiating antimicrobial effects against XDR strains of Staphylococcus aureus and Pseudomonas aeruginosa, suggesting their probably potential as candidates for addressing nosocomial pathogens. They exhibited significant suppression of efflux pump activity, indicating a possible successful inhibition of this mechanism. Moreover, all substances effectively inhibited biofilm formation, while showing minimal cytotoxicity. However, further advancement to clinical trials is needed to evaluate the feasibility of utilizing CGA and CL for reversing bacterial XDR efflux and determining their efficacy against biofilms. These trials will provide valuable insights into the practical applications of these compounds in combating drug-resistant infections.

Antifungal activity of synthetic xanthenone against fluconazole-resistant Candida auris and its mechanism of action.

Candida auris, an emerging multidrug-resistant fungal pathogen discovered in Japan in 2009, poses a significant global health threat, with infections reported in about 25 countries. The escalation of drug-resistant strains underscores the urgent need for new treatment options. This study aimed to investigate the antifungal potential of 2,3,4,4a-tetrahydro-1H-xanthen-1-one (XA1) against C. auris, as well as its mechanism of action and toxic profile. The antifungal activity of XA1 was first evaluated by determining the minimum inhibitory concentration (MIC), time-kill kinetics and biofilm inhibition. In addition, structural changes, membrane permeability, reactive oxygen species (ROS) production, and in vitro and in vivo toxicity of C. auris after exposure to XA1 were investigated. The results indicated that XA1 exhibited an MIC of 50 µg/mL against C. auris, with time-kill kinetics highlighting its efficacy. Field emission scanning electron microscopy (FE-SEM) showed structural damage in XA1-treated cells, supported by increased membrane permeability leading to cell death. Furthermore, XA1 induced ROS production and significantly inhibited biofilm formation. Importantly, XA1 exhibited low cytotoxicity in human epidermal keratinocytes (HaCaT), with a cell viability of over 90 % at 6.25 µg/mL. In addition, an LD50 of 17.68 µg/mL was determined in zebrafish embryos 24 h post fertilization (hpf), with developmental delay observed at prolonged exposure at 6.25 µg/mL (48-96 hpf). These findings position XA1 as a promising candidate for further research and development of an effective antifungal agent.

Combined prevention and treatment measures are essential to control nosocomial infections during the COVID-19 pandemic.

Severe acute respiratory syndrome coronavirus-2 is a highly contagious positive-sense, single-stranded RNA virus that has rapidly spread worldwide. As of December 17, 2023, 772838745 confirmed cases including 6988679 deaths have been reported globally. This virus primarily spreads through droplets, airborne transmission, and direct contact. Hospitals harbor a substantial number of confirmed coronavirus disease 2019 (COVID-19) patients and asymptomatic carriers, accompanied by high population density and a larger susceptible population. These factors serve as potential triggers for nosocomial infections, posing a threat during the COVID-19 pandemic. Nosocomial infections occur to varying degrees across different countries worldwide, emphasizing the urgent need for a practical approach to prevent and control the intra-hospital spread of COVID-19. This study primarily concentrated on a novel strategy combining preventive measures with treatment for combating COVID-19 nosocomial infections. It suggests preventive methods, such as vaccination, disinfection, and training of heathcare personnel to curb viral infections. Additionally, it explored therapeutic strategies targeting cellular inflammatory factors and certain new medications for COVID-19 patients. These methods hold promise in rapidly and effectively preventing and controlling nosocomial infections during the COVID-19 pandemic and provide a reliable reference for adopting preventive measures in the future pandemic.