Objective To study the disinfection efficacy of a dielectric barrier discharge (DBD) deep ultraviolet light source under ice-covered conditions and to provide a research basis for the subsequent application of ultraviolet disinfection technology under ice-covered conditions. Methods Using the carrier quantitative germicidal test method, DBD far-ultraviolet rays were used to kill bacterial vegetative cells and viruses on the slide carrier under low temperature ice conditions, and the disinfection effect of DBD far-ultraviolet light source was observed by comparing the protein content in the bacterial suspension before and after ultraviolet rays. Results At an ambient temperature of -20℃, DBD far-ultraviolet radiation with a dose of 30 mJ/cm² transmitted through an ice layer with a thickness of 50 mm, and the killing rates of Escherichia coli and Staphylococcus aureus were >99.9%, and the logarithm inactivation of H1N1 influenza A virus, enterovirus type 71 and poliovirus type I vaccine strains all reached 4.0. DBD far ultraviolet radiation dose of 150 mJ/cm² was irradiated on the glass carrier through a 50 mm thick ice layer, and the killing rate of Escherichia coli was >99.999%, and the killing rate of Staphylococcus aureus reached 100.0%. After irradiation of Escherichia coli and Staphylococcus aureus suspensions with DBD far-ultraviolet (far-UV) light sources at doses of 150, 300 and 600 mJ/cm², the extracellular protein content increased with higher irradiation doses (F=20.541 and 35.762, P<0.001). Conclusion Under low temperature conditions, DBD deep ultraviolet light irradiation with a radiation dose of ≥30 mJ/cm² can effectively kill two kinds of bacterial propagates and three kinds of viruses on the slide carrier.

Objective To study the disinfection efficacy of 9 chemical disinfectants on bacteria isolated from clean areas and to provide a reference for effective disinfection in clean areas. Methods The suspension quantitative bactericidal test was adopted. Three concentrations of high, medium and low were selected to observe the bactericidal effects of nine common disinfectants on six types of bacterial vegetative cells such as Staphylococcus epidermidis and three types of bacterial spores such as Bacillus cereus spores. Results Effective disinfection of six types of bacterial vegetative cells was achieved by treating with 500 mg/L didecyldimethylammonium chloride or 600 mg/L sodium hypochlorite for 2 min. Effective disinfection of Bacillus cereus spores was achieved by treating with a combination of 55 g/L hydrogen peroxide and 800 mg/L peracetic acid and 5 g/L didecyldimethylammonium chloride acting for 30 min. Effective disinfection of Bacillus subtilis spores was achieved by using a complex of 1 500 mg/L benzalkonium chloride and 150 mg/L polyhexamethylene biguanide hydrochloride for 3 min. Effective disinfection of Bacillus licheniformis spores was achieved by treating with 2 g/L benzalkonium bromide for 2 min. Conclusion The nine types of chemical disinfectants can effectively kill the selected experimental microorganisms, and the concentration and duration of action are verified to ensure the expected disinfection effect.

Objective To investigate the influence of varying concentrations of organic interferents on the disinfection efficacy of hypochlorous acid (HOCl), for providing a scientific basis for optimizing the use condition of disinfection in practical applications. Methods A quantitative suspension bactericidal test was conducted to evaluate the disinfection efficacy of HOCl solutions containing 137.2 mg/L and 68.6 mg/L available chlorine against Staphylococcus aureus, Escherichia coli, and Candida albicans in the presence of different concentrations of bovine serum albumin (BSA) used as the organic interferent. Results For hypochlorous acid disinfectant containing 137.2 mg/L available chlorine: when BSA concentration in the bacterial suspension was below 3.0%, a 0.5 min contact time achieved the disinfection standard against Escherichia coli, Staphylococcus aureus and Candida albicans. At 10.0% BSA concentration, the disinfectant failed to meet the standard for all tested microorganisms even after 1.5 min of exposure. For hypochlorous acid containing 68.6 mg/L available chlorine: with 0.3% BSA in suspension, over 1 min of contact time was required to meet the disinfection standard. When BSA concentration increased to 3.0%, the disinfectant failed to achieve the disinfection standard for all tested microorganisms after 1.5 min of action. Conclusion The lower the concentration of BSA, the better the disinfection effect of HOCl achieves. During the application of HOCl, the concentration of organic interfering substances should be reduced to improve its disinfection efficacy.

Objective To test in vitro and field bactericidal efficacy of normal temperature and low temperature formulations of potassium monopersulfate composite salt disinfectant against bacterial vegetative cells, and to evaluate their disinfection performance on object surfaces. Methods The quantitative bactericidal test method using cloth carrier immersion and on-site disinfection test method were used to assess the efficacy of 1 500 and 1 000 mg/L potassium monopersulfate composite salt disinfectant formulations both at normal temperature and low temperature against Escherichia coli and Staphylococcus aureus. Results Under normal temperature (20℃), the 1 000 mg/L potassium monopersulfate composite salt disinfectant reduced the bacterial count of Escherichia coli and Staphylococcus aureus on cloth carriers by more than 4.0 log within 5 min. Under low temperature (-18℃), the low temperature disinfectant with a concentration of 1 000 mg/L reduced the bacterial count of Escherichia coli and Staphylococcus aureus by more than 4.0 log and 3.0 log within 7.5 min, respectively. The 1 000 mg/L normal temperature formulations potassium monopersulfate composite salt disinfectant eliminated the natural bacterial count on object surfaces within 10 min, with an average killing rate of 95.59%. Conclusion Both normal temperature and low temperature potassium hydrogen peroxymonosulfate compound disinfectants can effectively eliminate bacterial vegetative cells, and they are suitable for disinfecting object surfaces under normal and low temperature conditions.

Objective To verify the accuracy of a self-made available chlorine concentration testing pen in measuring available chlorine content, and to provide scientific basis for practical clinical applications. Methods Using the iodometric method as a reference method, the accuracy of the available chlorine concentration testing pen for measuring the available chlorine content of chlorine-containing disinfectants was analyzed. Additionally, the G-1 type disinfectant concentration test paper was used to test the chlorine content of the same chlorine-containing disinfectant, and the consistency of the test results was compared. Results When the available chlorine concentration of the disinfectant was in the range of 300 - 1 500 mg/L, the test pen's measurement values showed consistent agreement with the iodometric method (P>0.05). For the same chlorine-containing disinfectant solution, the test pen demonstrated higher detection accuracy than test paper. The test results of chlorine disinfectant in use showed that the alarm rate of test pen was similar to the abnormal rate of conventional monitoring (53.86% vs 55.79%; χ²=0.085, P=0.771), with the false negative rate of 14.29% and the missed rate of 15.09%. The accuracy of the available chlorine concentration test pen showed no significant change within 100 usages. Conclusion When the concentration of chlorine disinfectant is in the range of 300 -1 500 mg/L, the available disinfection concentration test pen can replace the iodometric method to detect the available chlorine concentration of chlorine-containing disinfectant.

Objective To study the application effect of double-chain quaternary ammonium salt disinfectant in preventive disinfection on the surface of environmental objects of nursery institutions. Methods Thirty desktops and bathroom countertops were randomly selected from the classrooms of a nursery institution, and each sample was divided into two areas, the experimental group was disinfected with double-chain quaternary ammonium salt and the control group was disinfected with chlorine-containing disinfectant. Samples were collected at 0, 2, 4 and 8 h after disinfection, respectively, and colony counts were carried out. Results 61 strains of microorganisms were detected on the surface of environmental objects in a nursery institution. The qualified rate of disinfection was 100% in both experimental group and control group 0 h after disinfection of the desktops and bathroom countertops. At 2 h, 4 h and 8 h after disinfection, the qualified rates of the experimental group were 100%, 93.33% and 83.33%, and those of the control group were 90.00%, 76.67% and 53.33%, respectively. The qualified rates of the experimental group and the control group were 53.33% and 56.67% respectively at 2 h after disinfection, and 0% at 4 h and 8 h after disinfection. The average colony number of the experimental group was lower than that of the control group at 4 h and 8 h after desktop disinfection, with statistical significance (P<0.05). Conclusion Double-chain quaternary ammonium salt disinfectant has a sustained effect in the preventive disinfection of environmental surfaces in nursery institutions, and the frequency of disinfection needs to be increased in wet special environments.

Objective To understand the current situation of quality management of central sterile supply department (CSSD) in Gansu Province, and to provide a basis for further improving the quality of CSSD work. Methods A questionnaire survey was used to investigate and analyze the quality of CSSD management in 62 hospitals in Gansu Province. Results The proportion of secondary hospitals and tertiary hospitals with a floor area-to-hospital bed ratio ≥0.8 was 68.18% and 33.33%, respectively. The number of CSSD personnel per 100 beds >2 in secondary and tertiary hospitals accounted for 65.91% and 16.67%, respectively. Hospitals that adopt centralized management accounted for 85.48%, while hospitals that use centralized processing of soft endoscopes had the lowest proportion (27.42%). The implementation rates of CSSD for quantitative cleaning effect monitoring and temperature-pressure monitoring of cleaning and disinfection equipment were 46.77% and 50.91%, respectively. The pass rate of overall work quality and the pass rate of work quality evaluation in secondary and tertiary hospitals were 88.89%, 72.58% and 65.91%, respectively. Conclusion It is necessary to further optimize basic infrastructure, strengthen centralized management and standardized awareness, and to improve the quality of work.

Objective To understand the current situation of disinfection capacity of key places in Shanghai and to provide a scientific basis for improving Shanghai's public health emergency disinfection capabilities. Methods Using stratified sampling and questionnaire survey methods, this study investigated the disinfection capacity of 231 key places in Shanghai, and analyzed the distribution characteristics of disinfection personnel, related training, and the reserve status of disinfection equipment. Results Among 231 key places, 192 were equipped with disinfection personnel, accounting for 83.12%. A total of 2 388 disinfection personnel were deployed, including 1 390 full-time disinfection personnel and 998 reserve disinfection personnel. Institutions with full-time disinfection personnel accounted for 60.61%. Childcare institutions and elderly care institutions had a relatively high proportion of disinfection personnel allocation, which were 91.40% and 85.71% respectively, while medical institutions had a low allocation proportion, only 67.86%. The median number of disinfection personnel allocated was the highest in childcare institutions and schools (10 persons each), and 5 persons each in elderly care institutions and medical institutions. The educational structure of these disinfection personnel was relatively low, with those having a junior high school education or below accounting for 46.52%. 55.19% of the disinfection personnel received training or drill frequency of 1-2 times per year. 96.54% and 90.48% of the key places had sufficient reserves of hand disinfectants and surface disinfectants, while only 63.20% of the institutions had reserves of air disinfectants. Conclusion Disinfection personnel in key places in Shanghai are understaffed, with low academic qualifications and insufficient training. It is necessary to enhance the allocation of full-time disinfection personnel and the level of material reserves in key places.

Objective To investigate the risk factors for surgical site infection (SSI) after removal of internal fixation devices in fracture patients, aiming to facilitate effective prevention and control of hospital-acquired infections. Methods A retrospective analysis was conducted on clinical and laboratory data from 62 patients with SSI and 186 non-infected patients after internal fixation removal. Univariate and multivariate logistic regression analyses were used to identify risk factors for SSI. A nomogram prediction model was established using R software, followed by evaluation via receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis. Results Multivariate analysis identified diabetes, obesity, low preoperative albumin level, prolonged preoperative hospital stay, and extended operative time as independent risk factors for SSI (P<0.05). The prediction model was formulated as: logistic(P)=4.365+1.496×diabetes+1.447×(BMI≥28 kg/m²) -0.196×preoperative albumin level+0.914×preoperative hospital stay+0.026×operative time. The ROC curve area under the curve (AUC) was 0.83 (95% CI 0.76-0.91), with a sensitivity of 91% and specificity of 65%. Conclusion Independent risk factors for SSI following removal of internal fixation devices for fractures include diabetes, obesity (BMI≥28 kg/m²), low preoperative albumin level, prolonged preoperative hospitalization, and extended operative time. The nomogram model demonstrates robust predictive performance for clinical use.

Objective To understand the disinfection quality compliance status of primary and secondary schools and kindergartens in Aral City from 2020 to 2023, and to provide a basis for improving the disinfection quality of schools in the city. Methods The quality of preventive disinfection of tableware and environmental object surfaces in 64 primary and secondary schools and kindergartens was monitored and evaluated by on-site sampling and bacterial quantitative detection methods. Results A total of 3 794 samples were collected, with an overall pass rate of 89.17%. The disinfection compliance rates for middle schools, primary schools, and kindergartens were 87.66%, 91.02%, and 89.62% respectively. Schools in urban areas demonstrated higher compliance rates than those in the regimental farm ( 95.41% vs 85.77%; χ²=65.439, P<0.05 ). Tableware showed the highest disinfection compliance rate at 97.30%, while light switches, door handles, and faucets had lower rates ( all <85.00% ). Canteens and public areas achieved the relatively high disinfection qualification rates (>95.00% ), whereas toilets registered a relatively low rate of 77.43%. Conclusion The disinfection quality of primary and secondary schools as well as kindergartens in Alar City is generally good. However, the qualification rate of disinfection quality decreases slightly in 2023. It is necessary to actively consolidate the weak links in disinfection quality management, for improving the regular inspection and evaluation mechanism, and to strengthen the implementation of disinfection measures in schools in the regimental areas.

Objective To study the influencing factors of intracranial infection in patients after neuronavigation-assisted puncture drainage for intracerebral hemorrhage, and to provide the prevention and control of postoperative infection. Methods The clinical data and laboratory etiological examination data of patients with intracranial infection after neuronavigation-assisted puncture drainage for spontaneous intracerebral hemorrhage in a hospital were investigated retrospectively. Univariate and multivariate logistic regression analysis were used to analyze the influencing factors of intracranial infection. Results A total of 145 patients undergoing hematoma puncture and drainage were enrolled in this study. Postoperatively, intracranial infection occurred in 36 cases, with an infection rate of 24.8%. Among these infected patients, 5 strains of pathogenic bacteria were identified in cerebrospinal fluid, including 4 Gram-positive strains and 1 Gram-negative strain. Multivariate analysis indicated that preoperative GCS score≤8, no preoperative administration of antibiotics, and drainage tube indwelling time≥3 d were independent risk factors for intracranial infection following neuronavigation-assisted hematoma puncture and drainage. Conclusion The incidence of intracranial infection in patients undergoing intracerebral hematoma drainage in this hospital is relatively high. Patients with preoperative coma, no antibiotics, and drainage tube indwelling time ≥3 d are at high risk for intracranial infections, and the perioperative management of such patients should be strengthened.

Objective To investigate the current situation of water pollution from oral treatment tables in oral medical institutions in Pudong New Area, and to analyze the existing problems, so as to provide a basis for further improving the quality of treatment water. Methods Through on-site sampling and quantitative bacterial detection, the qualified rate of treatment water in various types of oral diagnosis and treatment institutions at all levels were monitored and analyzed. Results A total of 520 samples of water for oral diagnosis and treatment were collected from 2019 to 2023, with an average total qualified rate of 55.19%. There were statistically significant differences in the qualified rate of water for oral diagnosis and treatment in different years, different levels of medical institutions, different types and different treatment methods (P<0.05). Among the categories, 2021 (31.06%), secondary hospitals (42.86%), mobile phone water spraying (45.38%), and no treatment (42.65%) were seriously polluted. Conclusion The current situation of bacterial pollution in the treatment of water in oral diagnosis and treatment institutions in Pudong New Area is relatively low, and excessive bacterial contamination is common. It is necessary to strengthen the monitoring of treatment water and efforts to improve water quality in oral medical institutions at all levels in this area.

Objective To understand the status of object surfaces and medical staff's hand hygiene in medical institutions in Xi'an, and to explore measures to improve the hygienic qualification rate of object surfaces and medical staff's hand. Methods From 2020 to 2023, on-site sampling and quantitative bacterial detection methods were employed to monitor both object surfaces and medical staff's hand hygiene qualification rates in three medical institutions of different levels in Xi'an and the monitoring results were analyzed. Results Among 700 collected samples, the overall qualification rate was 75.86%. Object surfaces showed an average qualification rate of 82.72%. The qualification rate of operating rooms was 100%, that of intensive care units (ICU) was 81.51%. The qualification rate of surgical hand antisepsis reached 92.86%, whereas the routine hand hygiene qualification rate was merely 59.66%. The qualification rate of medical staff's hand hygiene in neonatal care units, ICU, outpatient and emergency department and stomatology was 100%, 73.33%, 49.20% and 40.74%, respectively. Conclusion While environmental surface hygiene in the surveyed medical institutions is satisfactory, medical staff's hand hygiene quality requires improvement, necessitating stricter monitoring and management.

Objective To observe the application effect of an integrated mobile rack for disinfection supply in improving the work efficiency of the disinfection supply center (CSSD). Methods A total of 64 CSSD staff members from two hospitals of similar type and scale were selected as research subjects. They were randomly divided into two equal groups: the observation group utilized disinfection supply-integrated mobile racks for instrument processing, while the control group employed conventional procedures. The work efficiency of the packaging process for instruments awaiting sterilization was tested and compared between the two groups for instrument processing. Results Compared with the control group, the observation group showed shorter tool retrieval time (3.00 s vs 8.45 s), shorter single-package operation movement distance (0.54 m vs 4.91 m), lower tool damage rate (1.56% vs 7.03%), and lower label processing error rate (6.00% vs 20.00%). The staff in the observation group demonstrated higher work enthusiasm and better environmental cleanliness (P<0.05), while showing lower fatigue index (P<0.05). Conclusion The use of integrated mobile carrier for disinfection supply can effectively improve the efficiency and quality of CSSD work.

Objective To study the influencing factors of the rust removal effect on reuse medical devices with different rust degrees to further standardize the rust removal procedure. Methods A total of 1 440 reusable medical devices (480 each with mild, moderate, and severe rust) were collected. The devices were randomly assigned to different rust remover temperatures (50℃, 60℃, 70℃, 80℃) and different rust removal times (5, 10, 12, 15 min). The rust removal result of each device was recorded. Single factor and multiple factor logistic regression analysis were used to investigate the factors affecting the rust removal effect of medical instruments. Results A total of 1 440 reusable medical devices was treated with rust removal, and the failure rate of rust removal effect was 27.99%, with the highest proportion of unqualified cases in severely rusted devices. respectively. Multivariate logistic regression analysis showed that the risk factors for unqualified rust removal were moderate rust (OR=22.332) and severe rust (OR=577.321), while the protective factors for rust removal effect were rust remover temperatures of 70℃ (OR=0.409) and 80℃ (OR=0.273), and rust removal times of 10 min (OR=0.562), 12 min (OR=0.344), and 15 min (OR=0.250). Conclusion The rust removal effect on reused medical devices is affected by factors such as rust degree, rust remover temperature and rust removal time. Appropriately increasing the rust remover temperature and extending the rust removal time can improve the rust removal effect on the devices.