Objective To evaluate the environmental temperature adaptability, rapid disinfection efficacy, and safety of the pulsed-driven 222 nm ultraviolet light source. Methods The electrical, optical characteristics, and operational stability of the 222 nm ultraviolet light source were investigated across a wide temperature threshold range. The disinfection effect of this light source against common pathogenic microorganisms, its irritancy to the skin and eyes of laboratory animals, and the safety of ozone concentration generated in simulated field environments were evaluated. Results The pulse-driven 222 nm ultraviolet light source could operate continuously and stably for 180 min at -40℃, with an irradiance increase of 17.3％. After passing through a three-dimensional disinfection door for 30 s, the logarithmic reduction values for Escherichia coli, Staphylococcus aureus, and H1N1 influenza A virus were all greater than 3.00. The average scores for congestion and edema of the cornea, iris, and conjunctiva in animal eyes were 0, and the average scores for erythema and edema of animal skin were also 0. The equipment was turned on for 20 min, and the ozone concentration in the middle position of the equipment channel was less than 0.05 mg/m3, meeting the requirements of the national standard GB 28235—2020 (≤0.1 mg/m3). Conclusion The pulse-driven 222 nm ultraviolet light source exhibits excellent environmental temperature adaptability, rapid disinfection effect on pathogenic microorganisms, and high safety performance.
Objective To understand the contamination characteristics and species distribution of airborne bacteria in dental clinics, so as to provide a basis for formulating targeted infection prevention and control measures for air microbial. Methods The plate settling method was employed to assess the airborne bacterial contamination levels in various consultation rooms within the department of stomatology of a hospital, and to evaluate the disinfection effect of medical air sterilizers. Differences in airborne bacterial community structures across different clinics were explored in this study using 16S rRNA gene sequencing and bacterial clustering analysis. Results Prior to the commencement of clinical services, bacterial counts detected in the air within all consultation rooms were < 4 cfu/(5 min·plate). Two hours after service began, the bacterial colony counts in the consultation room increased significantly, with the average bacterial count at a distance of 0.5 m from the treatment chair reaching as high as 62 cfu/(5 min·plate). Following the completion of clinical procedures, the bacterial levels in the consultation room declined. Concurrent with the start of clinical services, medical air disinfection units were activated for disinfection treatment; two hours after service commenced, the airborne bacterial colony counts at distances of 0.5, 1.0, and 1.5 m from the treatment chair were approximately 4 cfu/(5 min·plate). Analysis of bacterial 16S rRNA profiles revealed that the oral and maxillofacial surgery department exhibited the highest bacterial abundance (ACE=2 383.563, Chao1=2 510.148), while the dental implantology department showed the lowest bacterial abundance (ACE=318.732, Chao1=315.200). The Shannon index value was the highest in the oral and maxillofacial surgery department (9.287). Bacterial clustering analysis revealed distinct specialty-specific bacterial compositions across different consultation rooms, with anaerobic bacteria exhibiting the highest relative abundance in the dental caries and pulp therapy department. Conclusion The level of airborne bacterial contamination in the dental clinic of this hospital is closely associated with clinical procedures. The bacterial populations exhibit high diversity and possess unique characteristic features. Therefore, enhanced management of procedures within the dental clinic that are prone to generating aerosols during clinical practice is warranted, and it is recommended to implement disinfection protocols based on the operational intensity of each procedure.
Objective To observe the stability and peracetic acid endoscopic disinfectants of concentration changes during use, so as to provide guidance for their continuous application in endoscope disinfection.Methods The concentrations of three brands of peracetic acid disinfectants at different usage time points and the residual active ingredient levels in final rinses were evaluated using iodometric titration and test strip methods. Results For the three brands of peracetic acid disinfectants with initial active ingredient concentrations of 2.1-2.8 g/L, the peracetic acid concentration measured by two methods remained above 1.0 g/L for 14 d after initial opening, with the concentration decline rates being 38.5％, 53.8％, and 28.5％ respectively. When the test strip method indicated the endpoint concentration (1.0 g/L), the iodometric titration method confirmed the concentration was still above 1.0 g/L. After the first opening and multiple subsequent uses, iodometric titration showed decline rates of 23.1％, 46.2％, and 14.5％ at the final usage time. Following the specified number of cleaning and disinfection cycles, the residual peracetic acid concentration in endoscope rinse water was ≥0.04 g/Lfor all brands. Conclusion There are differences in the stability of the three brands of peracetic acid endoscope disinfectants, and the test strip method and iodometric method yield determination results that are not entirely consistent. Therefore, during use, the concentration of peracetic acid disinfectant should be monitored more closely.
Objective To monitor indoor air pathogenic microorganisms in hospitals using novel technologies, and to analyze the species distribution characteristics of airborne pathogenic microorganisms, so as to identify potential risks of disease transmission via aerosols. Methods Air samples were collected from selected outpatient clinics of three hospitals and analyzed for pathogenic microorganism species and drug resistance using an aerosol collection and enrichment device, multiplex PCR, and third-generation nanopore sequencing technology. Results A total of 36 indoor air samples were collected, with 25 samples containing 45 species of suspected colonizing bacteria. Moraxella osloensis and Staphylococcus epidermidis had the highest detection rates (both 30.56％), followed by Staphylococcus humanus subsp. humanus and Micrococcus luteus (both 25.00％). A total of 29 pathogenic or opportunistic pathogenic microorganisms were detected in 21 samples, including 21 bacterial species (such as Staphylococcus aureus, Klebsiella aerogenes, Acinetobacter baumannii, Pseudomonas maltophilia, Enterobacter hoffmannii, and Enterobacter cloacae), 6 fungal species (such as Candida albicans, Candida parapsilosis, and Candida tropicalis), and 2 viruses (SARS-CoV-2 and EB virus). VIM, NDM, and OXA-23 resistance genes were detected in Enterobacter hoffmannii, Klebsiella pneumoniae, Citrobacter freundii, and Acinetobacter baumannii. Conclusion The air in three medical institutions is severely contaminated with pathogenic microorganisms, necessitating enhanced indoor ventilation and environmental cleaning and disinfection. Pathogens in hospital environmental air can be rapidly detected using air enrichment and multiplex PCR methods, while third-generation nanopore sequencing technology enables early determination of pathogen drug resistance.
Objective To investigate the application efficacy and other pertinent properties of acidic electrolyzed oxidizing water (AEOW) for surface disinfection of hemodialysis machines, thereby furnishing a scientific basis for its utilization in surface disinfection of blood purification settings. Methods Using quantitative bacterial detection, 20 hemodialysis machines from a designated hospital were randomly assigned to experimental and control groups. The experimental group received AEOW disinfection, while the control group used a chlorine-containing disinfectant with available chlorine of 500 mg/L. Disinfection effect, metal corrosion resistance, and user acceptability were then compared and evaluated between the two groups. Results The bacterial counts detected on the surfaces of hemodialysis machines disinfected with AEOW and chlorine-containing disinfectants were both ≤10 cfu/cm2, achieving a 100％ disinfection qualified rate for both approaches. The disinfection time was 5 min for the experimental group using AEOW, whereas it was 30 min for the control group using chlorine-containing disinfectants. Lower corrosivity toward metallic materials was observed for AEOW, and no irritating odor was detected; its acceptability among healthcare personnel was rated superior to that of chlorine-containing disinfectants. Conclusion AEOW exhibits rapid bactericidal efficacy, low corrosiveness, as well as excellent safety and environmental friendliness; these characteristics confer significant application advantages for surface disinfection of hemodialysis machines, making it an ideal alternative for surface disinfection in blood purification environments.
Objective To understand the current status of surface contamination and disinfection effect of medical ultrasound probes, and to provide a scientific basis for the formulation of relevant standards and regulations. Methods The bioluminescence (ATP) method and on-site disinfection effect testing method were employed to detect and evaluate bacterial contamination before disinfection and disinfection status of various types of medical ultrasound probes after clinical used in a hospital. Results A total of 95 medical ultrasound probes were examined using the ATP bioluminescence assay, with an overall hygiene qualified rate of 72.63％. The qualified rates for high-risk, medium-risk, and low-risk medical ultrasound probes were 64.29％, 100.00％, and 76.09％, respectively. Using the disinfection effect testing method, 324 ultrasound probes of various categories were tested both before and after disinfection. The overall bacterial detection rate was 41.36％ before disinfection, with a hygiene qualified rate of 83.95％. The bacterial detection rate decreased to 21.60％ after disinfection, with a disinfection qualified rate of 94.14％. The predominant bacteria isolated from ultrasound probe surfaces were Staphylococcus hominis and Staphylococcus epidermidis, accounting for 28.46％ and 18.29％, respectively. Burkholderia cepacia accounted for 3.66％. Conclusion The surface bacterial carriage rate of medical ultrasound probes used in this hospital is relatively high, with coagulase-negative Staphylococci being the predominant contaminants. The use of 500 mg/L compound double-chain quaternary ammonium salt disinfectant shows a certain level of disinfection effect on ultrasound probe surfaces.
Objective To investigate the concentration and distribution of disinfection by-products (DBPs) in drinking water in Kunshan, and to provide a basis for ensuring the safety of drinking water quality. Methods On-site sampling and chemical testing methods were adopted to monitor and assess the concentrations of 8 types of DBPs in residential drinking water, in accordance with Standard Examination Methods for Drinking Water (GB/T 5750—2023). Results A total of 280 residential drinking water samples were collected in Kunshan, and the concentrations of all eight DBPs were below the limit values. The concentrations of the eight DBPs showed statistically significant differences among different types of water samples (P<0.05). The DBP concentrations were relatively lower in direct drinking water, while those in finished water, secondary supply water, or tap water were higher. Chlorite concentrations in urban water samples were lower than those in rural water samples (P<0.05). Among water samples collected in different seasons, the concentrations of seven DBPs exhibited significant differences (P<0.05) with the exception of dichloroacetic acid. The DBP concentrations were relatively higher in samples taken during the wet season. Conclusion The overall quality of residential drinking water in Kunshan City is favorable, and the concentrations of DBPs in water are all below the standard limits. Water sample type and season are important factors influencing the variation of DBP levels in drinking water in Kunshan.
Objective To explore the clinical features and drug resistance of hospital-acquired pneumonia (HAP) caused by mucoid and non-mucoid Pseudomonas aeruginosa (PAE), for providing a reference for clinical diagnosis and treatment. Methods A total of 133 patients with HAP caused by PAE admitted to a hospital in Suzhou were enrolled in this study. According to the colony morphology of PAE cultured from clinically submitted sputum specimens, the patients were divided into the mucoid PAE infection group (55 cases) and the non-mucoid PAE infection group (78 cases). A retrospective survey was conducted to analyze the clinical characteristics, antimicrobial resistance profiles, and risk factors associated with acquired antimicrobial resistance in both groups. Results Compared to patients with mucoid PAE infection, those with non-mucoid PAE infection had a higher proportion of males (66.7％ vs 40.0％, P=0.002), higher rates of surgery and related invasive procedures before diagnosis (P<0.001), more significant elevations in serological inflammatory indicators except lymphocytes (P<0.05), a higher prevalence of pleural effusion on imaging (52.6％ vs 30.9％, P=0.038), a higher rate of single-agent antimicrobial therapy (91.0％ vs 70.9％, P=0.003), and longer hospital stay (28.0 d vs 15.0 d, P<0.001). Both mucoid and non-mucoid PAE isolates exhibited the highest resistance rate to amikacin (92.7％ and 92.3％, respectively). Mucoid PAE showed the highest resistance rate to levofloxacin (55.6％), and its resistance rates to ceftazidime and cefepime were significantly higher than those of non-mucoid PAE (P<0.05). Multivariate analysis revealed that serum total bilirubin and albumin levels on admission were independent risk factors for acquired antimicrobial resistance in PAE. Conclusion Clinical characteristics differ between patients infected with mucoid and non-mucoid PAE. Targeted treatment strategies should be implemented, with antimicrobial agents selected rationally based on susceptibility testing. Additionally, clinicians should remain vigilant for host dysfunctions that may contribute to PAE resistance.
Objective To analyze the distribution characteristics and drug resistance of pathogens isolated from respiratory specimens in a Mongolian medicine hospital, so as to provide guidance for the rational clinical use of antibiotics. Methods A retrospective survey was conducted to statistically analyze the pathogens and their antimicrobial susceptibility test results from specimens submitted by patients in this hospital from 2021 to 2024. Results A total of 9 921 respiratory specimens were collected, with a positive pathogen detection rate of 30.44％. A total of 3 139 strains were isolated, among which Gram-negative bacteria accounted for 84.26％, Gram-positive bacteria for 13.67％, and fungi for 2.07％. The top four pathogens in terms of constituent ratio were Klebsiella pneumoniae subsp. pneumoniae (21.25％), Acinetobacter baumannii (21.25％), Pseudomonas aeruginosa (18.64％), and Staphylococcus aureus (9.49％). From 2021 to 2022, A. baumannii ranked first (>20％), but dropped to third place in 2023. The detection rate of P. aeruginosa increased significantly from 16.25％ to 28.71％ (Z=4.724, P<0.001); the detection rate of K. pneumoniae increased from 17.66％ to 25.76％ (Z=2.860, P=0.004). In terms of drug resistance, the carbapenem resistance rate of K. pneumoniae increased from 7％ to 30％-31％, and the detection rate of carbapenem-resistant Enterobacterales (CRE) increased from 6.87％ to 23.61％ (Z=2.145, P=0.032). The resistance rates of A. baumannii to carbapenems, fluoroquinolones, and most cephalosporins were all >75％, and the detection rate of carbapenem-resistant A. baumannii (CRAB) remained above 69％. The carbapenem resistance rate of P. aeruginosa fluctuated between 25％ and 43％, and the detection rate of carbapenem-resistant P. aeruginosa (CRPA) showed a significant upward trend (Z=2.934, P=0.003). The carbapenem resistance rate of Escherichia coli was consistently <3％, and the tigecycline resistance rate was 0％. The detection rate of methicillin-resistant S. aureus (MRSA) remained stable at 25.0％ - 29.0％, and the resistance rates to vancomycin and linezolid were both 0％. Conclusion The predominant pathogens of respiratory tract infections in this hospital are Gram-negative bacilli. Particular attention should be paid to respiratory infections caused by P. aeruginosa. Continuous surveillance of bacterial resistance, combined with precise infection control measures and rational antimicrobial stewardship strategies, is necessary to reduce the emergence of drug-resistant organisms such as CRE, CRAB, and CRPA.
Objective To understand the current status of disinfection quality in different types of sentinel medical institutions in Nanyang City, so as to grasp the overall situation of disinfection work, identify weak links, and to provide a scientific basis for improving disinfection work in medical institutions. Methods According to GB 15982—2012 Hospital Disinfection and Hygiene Standards as well as other relevant standards, nine types of samples, including in-use disinfectants, object surfaces, medical water, and medical sewage, were collected and tested from 12 sentinel medical institutions in Nanyang City from 2023 to 2025, and the qualification status were evaluated. Univariate and multivariate logistic regression analyses were adopted to explore the influencing factors for sanitation qualification of medical water. Results A total of 2 334 samples were collected from 2023 to 2025, with an overall qualified rate of 94.00％. The disinfection qualified rates for each year were 96.95％, 90.78％, and 94.38％, respectively. Among all types of medical institutions, blood collection and supply institutions showed the highest overall disinfection qualified rate (97.43％), whereas clinics had the lowest rate (86.36％). The rates of general hospitals, specialized hospitals, maternal and child health hospitals, and community health service centers all exceeded 90％. Among different monitoring items, the qualified rate of the pressure steam sterilizer was the highest (100.00％), the qualified rates of medical water and sewage were relatively low, at 79.26％ and 55.00％, respectively. Compared with other medical institutions of the same type, secondary medical institutions, maternal and child health hospitals, stomatology departments, and endoscopy centers had significantly lower sanitation qualified rates of medical water (P<0.05). Conclusion The overall disinfection quality of sentinel medical institutions in Nanyang City is good, but medical water and sewage are still weak links. It is necessary to strengthen the training of full-time personnel for medical water and sewage treatment, improve disinfection measures, and continuously improve disinfection quality.
Objective To understand the hand hygiene effect and contamination status of medical staff in a certain tertiary hospital, in order to provide a basis for formulating targeted hospital infection prevention and control measures. Methods This study selected medical personnel from eight key departments as study subjects. Hand samples were collected for microbial culture and identification to compare disinfection effects. Additionally, 16S rRNA sequencing was performed to analyze the distribution characteristics of contaminated bacteria. Results A total of 192 samples were collected. The overall qualified rate of hand hygiene among medical staff was 67.19％. The qualified rate of surgical hand hygiene was 55.00％, and the qualified rates for doctors and nurses were 57.50％ and 52.50％, respectively, with no statistically significant difference (P>0.05); the qualified rate of hand hygiene was 75.89％, and the qualified rates for doctors and nurses were 68.75％ and 78.75％, respectively, with no statistically significant difference (P>0.05). The qualified rates of hand hygiene among medical staff in the maternity room and neonatal room were relatively high (>90％), while the lowest rate was in the dental department (56.25％), and the difference was statistically significant ($\chi^{2}$=13.957, P=0.030). The dominant pathogenic bacterial species were Staphylococcus epidermidis (29.62％), Staphylococcus warneri (21.95％), and Staphylococcus capitis (15.68％). Dominant bacterial genera on hands (relative abundance≥1％) included Pelomonas, Acidovorax, Acinetobacter, Phenylobacterium, Caulobacter, Streptococcus, and Cutibacterium. Conclusion Hand hygiene compliance among medical staff in this hospital is generally suboptimal, posing a risk of microbial contamination. There are notable differences in the microbial community structure across different departments. Therefore, it is imperative to enhance aseptic techniques and hand hygiene awareness, particularly emphasizing the indications for hand hygiene to prevent hospital-acquired infections.
Objective To investigate the current status of the abnormal sterilization parameters in the first cycle of pressure steam sterilizers in the central sterile supply departments (CSSD) of hospitals in Shanghai, thereby providing references for establishing steam quality analysis methods. Methods Using instrumental detection methods, the sterilization parameters of the first and second cycles of 30 large pulsating pressure steam sterilizers from 28 hospitals in Shanghai were examined. The extended exhaust pulse time of the first cycle, the prolonged heating time of standard PCD test packs, and the occurrence of wet packs were analyzed. The incidence of abnormal sterilization parameters in the first cycle under different conditions, including steam sources, types of loads, and sterilizer service life, was compared, and the factors affecting steam sterilization quality were analyzed. Results In the sterilization procedure involving 30 cycles, the probabilities of exhaust pulse delay, PCD test package heating delay, and wet package occurrence in the first cycle were 56.7％, 23.3％, and 13.3％, respectively. There was no statistically significant difference in the incidence of abnormal sterilization parameters in the first cycle between exogenous and endogenous steam sterilizers (82.4％ vs 53.8％, P=0.123). The incidence of abnormal sterilization parameters in the first cycle when loaded with dressing packs was higher than that when loaded with instrument packs (70.4％ vs 28.0％; $\chi^{2}$=9.321, P=0.002). Neither the loading capacity nor the service life of the sterilizer had a significant impact on the incidence of abnormal sterilization parameters (P>0.05). Conclusion The proportion of abnormal sterilization parameters for the first cycle of large pulsating steam sterilizers in the survey hospital CSSD is relatively high; therefore, enhanced monitoring of the first cycle during dressing pack sterilization is recommended to reduce the risk of sterilization failure.
Objective To investigate the current situation of healthcare-associated infection (HAI) management in medical institutions in Wuhan, and to propose improvement strategies. Methods The organizational development of HAI management, team development, HAI surveillance, and risk assessment in 199 medical institutions in Wuhan were investigated using a questionnaire survey. The distribution characteristics among different levels of medical institutions were analyzed. Results Of the 199 medical institutions, 89.45％ had established HAI management committees, 87.50％ had an independent HAI management department, 58.57％ recognized such departments as functional clinical departments with administrative authorities, and 42.86％ had independent funding. A total of 557 full-time HAI management staff were assigned across the 199 institutions; 63.02％ majored in nursing, 72.17％ had a bachelor’s degree or above, and 70.74％ held intermediate professional titles or higher; 45.96％ had working experience of no more than 4 years, and 78.64％ worked with valid practice certificates; the qualification rate of full-time staff was 84.92％; the qualification rate decreased with the increase of the number of beds ($\chi^{2}$=59.553, P<0.001). In total, 82.91％ of medical institutions carried out HAI surveillance, and only 30.15％ were equipped with information-based surveillance systems for HAI; 62.81％ actually carried out HAI risk assessment. Tertiary medical institutions performed better than secondary, primary, and unclassified medical institutions in team development, HAI surveillance, and risk assessment (P<0.05). Conclusion Medical institutions in Wuhan have established a relatively sound organizational system for HAI management with sufficient full-time staff. However, secondary and lower-level medical institutions face challenges, including ambiguous department positioning, and lagging information construction. Relevant administrative authorities should attach importance to these issues.
Objective To investigate the occurrence and related risk factors of recurrent urinary tract infections (UTIs) in hospitalized patients with Alzheimer's disease (AD). Methods A retrospective analysis was performed on the clinical data of hospitalized AD patients with UTIs at Lishui Second People's Hospital from January 2021 to December 2023. Patients were divided into a recurrence group and a single-episode group based on whether they experienced recurrence. Urine culture results were used to analyze the pathogen distribution and antimicrobial resistance profiles of the major pathogens. Clinical data were compared between the two groups, and risk factors for recurrent UTIs in hospitalized AD patients were identified. Results The recurrence rate of UTIs in hospitalized AD patients was 59.1％. The predominant bacterial species were Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. The resistance rates of these three pathogens to piperacillin-tazobactam, cefoperazone-sulbactam, and carbapenems were all below 10％. The resistance rates of E. coli isolates in the recurrence group to cefazolin, ceftriaxone, and ceftazidime were significantly higher than those in the single-episode group (P<0.05). AD duration of>5 years (OR=2.421, 95％CI = 1.168-5.019, P<0.05) and long-term indwelling urinary catheterization (OR=2.270, 95％CI =1.091-4.725, P<0.05) were identified as independent risk factors for recurrent UTIs in hospitalized AD patients. Conclusion The recurrence rate of UTIs in hospitalized AD patients is relatively high. Special attention should be paid to patients with AD duration of>5 years and those with long-term indwelling catheters. Personal hygiene should be maintained, and effective nursing interventions should be provided to reduce the recurrence of UTIs.
