Objective To investigate recovery effect of cyanuric acid from swimming pool water using melamine, and to determine the optimal recovery conditions, so as to provide experimental evidence for practical application. Methods The recovery of cyanuric acid from swimming pool water was tested using the melamine recovery method, liquid chromatography, and spectrophotometry. The content and recovery rate of cyanuric acid were verified, and the influencing factors were analyzed. Results The optimal reaction time for melamine and cyanuric acid was 20 min, and the optimal reaction ratio was between 1:1 and 1:1.2. Strong acidic and alkaline conditions were not favorable for the formation of precipitates between melamine and cyanuric acid, with the optimal pH value ranging from 6 to 7. Under the study conditions, the recovery rate of cyanuric acid from swimming pool water reached 84.70%. An appropriate concentration of PO43--P could enhance the recovery effect of cyanuric acid. The maximum recovery rate reached 98.54% when the concentration of PO43--P was 3 mg/L. Conclusion The application of melamine can efficiently recover cyanuric acid from swimming pool water, which realized the resource utilization and harmless treatment of swimming pool water.
Objective To observe the antibacterial effect of a compound of Chinese medicine and its cream in vitro. Methods Quantitative bacteriostatic test by carrier immersion and minimum inhibitory concentration (MIC) test were used to evaluate the bacteriostatic effect of a traditional Chinese medicine compound and its cream in vitro. Results The inhibition rates of Staphylococcus aureus, Escherichia coli and Candida albicans were 94.0%, 89.0% and 46.3%, respectively, after being treated with 50 mg/mL compound solution for 4 h. The antibacterial rates of the compound cream were 42.9%, 75.0% and 17.7%, respectively. The MIC of a Chinese herbal compound against Staphylococcus aureus, Escherichia coli and Candida albicans were 0.8, 0.8 and 12.8 mg/mL, respectively. The minimum bactericide concentration (MBC) of Staphylococcus aureus, Escherichia coli and Candida albicans were 3.2, 3.2 and 51.2 mg/mL, respectively. Conclusion The compound of traditional Chinese medicine and its cream have certain bacteriostatic effects on Staphylococcus aureus, Escherichia coli and Candida albicans.
Objective To study the design and application of medical electric drill sealed fully automatic cleaning sterilization machine. Methods By designing and manufacturing medical electric drill cleaning sterilization machine, 120 pieces of medical electric drill clips to be cleaned were randomly divided into 2 groups, using the cleaning machine cleaning (test group) and traditional manual cleaning method cleaning (control group), respectively. The cleaning effect of the instrument cleaning was tested using optical method, ATP biofluorescence detection method and sublimation test method, comparing the cleaning pass rate, cleaning time and staff satisfaction of the 2 groups. Results The cleaning sterilization machine designed in this study consisted of the main machine, mounting rack, operating table and cleaning unit. The difference between the cleaning of the test group and the control group was not statistically significant (96.67% vs 95.00%; P>0.05). The cleaning pass rate of the ATP biofluorescence test group was higher than that of the control group (96.67% vs 81.67%; χ2=6.988, P<0.05). The cleaning pass rate of the sublimation test group was higher than that of the control group (91.67% vs 78.33%; χ2=4.183, P<0.05). The average cleaning time of the test group was shorter than that of the control group (10.93 min vs 17.87 min; t=-94.840, P<0.05). Staff satisfaction with the test group's cleaning quality, cleaning efficiency, convenient operation, time-saving and labor-saving four aspects were higher than the control group (P<0.05). Conclusion The enclosed fully automatic medical drill chuck cleaning and disinfection machine designed in this study is easy for operation, time-saving and labor-saving, which improves the cleaning quality and efficiency of medical drill chucks.
Objective To observe the microbial inactivation effects of a LED ultraviolet (UV) irradiation device on different types of object surfaces, which device primarily emitting at a wavelength of 270 nm, so as to provide a reference for accurate disinfection. Methods Using a carrier quantitative bactericidal test method, the LED UV device irradiated at an intensity of 250 μΩ/cm on surfaces contaminated with Staphylococcus aureus, Escherichia coli, and human coronavirus (HCoV-229E). The bactericidal effects on various carriers were observed. Results After 32 s and 80 s of irradiation, corresponding to total doses of 8 mJ/cm2 and 20 mJ/cm2 respectively，the inactivation rates of bacteria and human coronavirus on contaminated surfaces, including fabric, glass slides, stainless steel sheets, plastic sheets, and wood chips exceeded 99.0%. Notably, the microbial inactivation efficacy of the LED UV device varied across different materials, with microorganisms on stainless steel and plastic surfaces showing significantly higher susceptibility to inactivation than those on other materials. Conclusion The LED UV irradiation device utilized in this study is capable of rapidly and effectively inactivating microorganisms on various object surfaces.
Objective To investigate the disinfection effect and safety of a new type of multi-effect composite air disinfection machine. Methods The disinfection effect and safety of the air sterilizer were analyzed and discussed by simulated field test and on-site test. Results The sterilizer combined plasma, ultraviolet light and photocatalyst and started disinfection for 120 min. The killing rate of the sterilizer on Staphylococcus albus in test chamber was 99.99%. The killing logarithm values were >4.00 against Escherichia coli and Staphylococcus epidermidis on contaminated glass slides. The killing rate for enterovirus EV71 and influenza A H1N1 were 100%, while the death rate of natural bacteria in the air exceeded 90%. Moreover, no leakages of ultraviolet and ozone were detected. Conclusion The sterilizer demonstrates significant effectiveness against a variety of microorganisms, without ultraviolet radiation and ozone leakage.
Objective To investigate the current status of key laboratory related indicators testing for disinfection products supervised and sampled in Zhejiang Province, and to provide scientific basis for the supervision of hygiene and safety of disinfection products. Methods Laboratory testing was conducted on disinfection products supervised and randomly inspected in Zhejiang Province from 2021 to 2023, and the results of key indicators testing were summarized and analyzed. Results A total of 652 disinfection product samples were tested, with a qualification rate of 84.5%. The qualification rate of disinfectants (including liquid dominated antibacterial and bacteriostatic agents) was 74.6%, and the qualification rates of their content, stability, and killing / sterilization (including antibacterial and bacteriostatic) effect were 79.9%, 88.2%, and 80.5%, respectively. The qualification rate of disinfection equipments was 82.9%, and the qualification rates of their physical and chemical indicators and microbial killing indicators were 100.0% and 70.0%, respectively. The qualification rate of cream based antibacterial agents was 91.7%. About 20% of the key laboratory indicators for market sampling disinfection products were unqualified. Conclusion The main reasons for the unqualified hygiene and safety supervision and inspection of disinfection products are the unqualified key laboratory related indicators. In the hygiene supervision of commercially available disinfection products, it is necessary to strengthen the monitoring of key laboratory indicators.
Objective To investigate the contamination status of pathogenic microorganisms on environmental surfaces in elderly care institutions, and to analyze the antibiotic resistance of pathogenic Enterococcus as well as their resistance to commonly used environmental disinfectants. Methods Field collection of environmental surface samples in elderly care institutions was conducted to assess the contamination status of pathogenic bacteria. Pathogenic Enterococcus were isolated, identified, and subjected to antibiotic susceptibility testing. Using the broth dilution method, the resistance of these pathogenic Enterococcus to chlorine-based disinfectants, ethanol, and quaternary ammonium compounds was evaluated. Results Among the 193 environmental samples, 20 strains of Staphylococcus aureus, 2 strains of Pseudomonas aeruginosa, and 19 strains of Enterococcus were detected, with detection rates of 10.4%, 1.0%, and 9.8% respectively. The Enterococcus included 9 strains of Enterococcus faecalis and 10 strains of Enterococcus faecium. The detection rate of Enterococcus faecium was higher in non-medical-elderly care institutions compared to that in medical-elderly care institutions (9.0% vs 1.1%; χ2=4.652, P=0.031). Among the 19 strains of Enterococcus, 68.4% were resistant to antibiotics, and 15.8% were multidrug-resistant. For some Enterococcus the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against chlorine-based disinfectants and monochain quaternary ammonium compounds were higher than those of standard strains. Conclusion The detection rate of Enterococcus on the environmental surfaces of elderly care institutions is relatively high, and some strains exhibit drug resistance and disinfectant resistance. Therefore, it is necessary to strengthen the environmental hygiene management in elderly care institutions, and to scientifically prevent and treat hospital acquired infections of pathogenic enterococci based on drug resistance and disinfectant resistance.
Objective To evaluate the disinfection by-products (DBP) and population health risks in drinking water in a certain district of Chongqing, so as to provide a scientific basis for ensuring drinking water safety. Methods The on-site sampling and physical and chemical analysis methods were used to monitor and assess the health risks of DBP in the drinking water of the area. Results A total of 94 water samples were monitored in the area, with detection rates of 99.0%, 85.0%, 81.0%, 1.1%, 100.0%, and 87.0% for trichloromethane, dichlorobromomethane, dichlorodibromomethane, tribromomethane, chlorate, and chlorite, respectively. The qualified rate of trichloromethane was 95.0%, with the highest content reaching 104.89 μg/L, which was 2.42 times the limit standard of GB 5749 —2022 Sanitary Standards for Drinking Water. The DBP content of other types was below the safety limit. The total carcinogenic risk and non carcinogenic risk of DBP exposure through drinking water were 43.10×10-6 and 22.19×10-2, respectively. Among different types of water samples, the DBP carcinogenic risk of liquid chlorine disinfection method was higher than that of chlorine dioxide disinfection method, the peripheral water was higher than the factory water, and the wet season was higher than the dry season. Conclusion DBP in drinking water in a certain district of Chongqing is basically controlled within the safe limit, but it is still necessary to strengthen the monitoring of trichloromethane and dichlorobromomethane indicators to ensure drinking water safety.
Objective To analyze the characteristics and risk factors of ventilator associated pneumonia (VAP) infection in patients with severe chest traum (SCT). Methods Retrospective analysis was used to analyze the VAP infection situation and risk factors with SCT from 2 hospitals in Huzhou City, Zhejiang Province. Results A total of 252 SCT patients were collected, of which 74 had VAP, with infection rate of 29.37%. 95 strains of pathogenic bacteria were isolated from 74 sputum samples, the detection rates of gram negative bacteria, gram positive bacteria and fungi accounting for 80.00%, 16.84% and 3.16% respectively. Multivariate analysis showed that the independent risk factors for VAP in SCT patients included age≥60 years, diabetes, days of mechanical ventilation≥7 d, CONUT score≥5 points, AIS score > 4 points. Conclusion The incidence of VAP infection is high in SCT patients, and gram negative bacteria is the main pathogen of infection. Effective prevention and control measures should be formulated for independent risk factors.
Objective To investigate the cleaning effect of self-made electric cleaning brush on the laparoscopic electrosurgical aspirators with coagulation function. Methods A total of 107 laparoscopic electrosurgical aspirators with coagulation function were divided into a control group and an experimental group. The control group was cleaned using traditional manual brushes, while the experimental group was cleaned with a self-made electric cleaning brush using a rotating and pulling method. The cleaning quality of the two groups was compared using ATP bioluminescence detection and the lumen instrument detection workstation method. Results The ATP bioluminescence detection results showed that the pass rate for the cleaning of the aspirator lumens in the experimental group was higher than that in the control group ( 91.07% vs 76.47%; χ2=4.258, P<0.05 ). The lumen instrument detection workstation examination results revealed that the pass rate for the cleaning of the aspirator lumens in the experimental group was also higher than that in the control group ( 87.50% vs 70.59%; χ2=4.674, P<0.05 ). Conclusion The use of the self-made electric cleaning brush with a rotating and pulling brushing method for manual cleaning of the lumens in laparoscopic electrosurgical aspirators with coagulation function，yield a satisfactory cleaning outcome. This method is characterised by its ease of operation and efficacy, thus meriting further promotion and wider dissemination.
Objective To investigate the epidemic distribution and drug resistance characteristics of methicillin resistant Staphylococcus aureus nosocomial infection in general ward and ICU. Methods Using a retrospective survey method, medical records and laboratory testing data were collected for 304 261 hospitalized patients from 2016 to 2020. The differences in MRSA infection rate, detection rate, and drug resistance between ICU and general ward patients were compared. Results A total of 263 cases of MRSA nosocomial infection occurred, with an infection rate of 0.09%. The case infection rate in ICU cases was higher than that in general wards (0.85% vs 0.04%; χ2=1 413.805, P<0.001). MRSA nosocomial infections were mainly caused by lower respiratory tract infections, with a higher incidence rate of ventilator-associated pneumonia infections in the ICU. The MRSA isolates were sensitive to vancomycin, teicoplanin and tigecycline. The resistance rate of MRSA isolates from ICU specimens to ciprofloxacin, moxifloxacin, and tetracycline was higher than that of general ward isolates (P<0.05). Conclusion ICU and general ward MRSA nosocomial infections often occur in the lower respiratory tract, and targeted measures should be taken to strengthen ICU nosocomial infection prevention and control. Drugs should be used reasonably based on drug sensitivity test results.
Objective To investigate the current status of disinfection work in disease prevention and control institutions (CDCs) at all levels in Anhui Province during the COVID-19 pandemic, and to provide insights for infectious disease control. Methods A questionnaire survey was conducted to evaluate the human resources and capabilities related to disinfection work in 100 CDCs across the province. Results A total of 100 valid questionnaires were collected, resulting in an effective recovery rate of 100.0%. Among the 100 CDCs, 31 (31.0%) had established disinfection departments. Prior to the pandemic, these 100 CDCs collectively employed 105 disinfection professionals, averaging 1.0 disinfection professional per institution. Six of the disinfection professionals held a master's degree or higher, and 12 held senior titles. Among the disinfection professionals, 42 (40.0%) had more than 10 years of work experience. In 2020, among the newly added disinfection personnel, 75.2% were under 50 years old, 55.8% had a college degree or lower, and 95.0% held mid-level or lower titles. Conclusion The proportion of CDCs with established disinfection departments in the province is relatively low, and there is a notable shortage of high-level disinfection professionals with advanced degrees and senior titles. Strengthening the disinfection workforce is imperative.
Objective To analyze the clinical epidemiological characteristics and drug resistance of carbapenem-resistant Acinetobacter baumannii (CRAB), so as to provide scientific basis for rational use of antibiotics and prevention and control of nosocomial infections caused by multi-drug resistant bacteria. Methods Using the retrospective survey method, the medical records and drug resistance test results of hospitalized patients with CRAB infection in a hospital from 2018 to 2023 were statistically analyzed, and the clinical distribution characteristics and drug resistance changes of CRAB infection were analyzed and compared. Results A total of 212 cases of CRAB nosocomial infection occurred in 6 years, and the total infection rate was 0.33‰. There was no significant difference in the incidence of CRAB infection between years (χ2trend= 0.346, P= 0.556). The main infection site was respiratory tract (79.25%), and the age of patients was more than 70 years old (44.09%). The main infection departments were comprehensive ICU (38.21%) and emergency ICU (30.19%), and the main source of CRAB samples was sputum (71.11%). The resistance rate of CRAB to imipenem, piperacillin/tazobactam and meropenem was as high as 100.00%, and the resistance rate to ceftriaxone, ceftazidime, cefepime and ciprofloxacin was more than 95.00%. The resistance rate to cefoperazone/sulbactam was the lowest (32.88%). Conclusion During the six years, the hospital has a good control of CRAB infection, but it is necessary to strengthen the management of ICU departments and transferred patients, and further standardize the clinical application of antibiotics.
Objective To investigate the incidence of nosocomial infection among hospitalized patients with cerebral infarction in China. Methods The literatures related to cerebral infarction in China from January 1, 2012 to December 31, 2021 were searched by PubMed, Embase, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, and Wanfang Data. A Meta-analysis of the incidence of nosocomial infection was conducted, along with sensitivity analysis and subgroup analysis of the incidence. Results A total of 12 literatures were included. The results showed that among 88 871 hospitalized patients with nosocomial infection in China, the incidence of nosocomial infection in cerebral infarction was 9.0% (95%CI 7.0%~10.0%; I2=94%, P<0.05). Patients with invasive procedures were higher than those without procedures (23.0% vs 4.0%; χ2=1 219.281, P<0.05), and patients with diabetes were higher than those without procedures (13.0% vs 10.0%; χ2=15.290, P<0.05). Conclusion Patients with cerebral infarction still face high risk of nosocomial infection, and early intervention should be conducted in patients with invasive operation and diabetic patients.
Objective To investigate the clinical and microbiological characteristics of nosocomial infections in kidney transplant recipients and to analyze the risk factors associated with infections, so as to provide a basis for prevention and control. Methods A retrospective study was conducted to collect the clinical and microbiological data of 168 patients who underwent kidney transplantation at a hospital from 2020 to 2022. The incidence of nosocomial infections and the pathogenic composition of patient specimens were analyzed. Univariate and multivariate regression analyses were performed to identify risk factors, and a predictive model was established. Results Among the 168 patients, 31 patients developed nosocomial infections, with an infection rate of 18.45%, and urinary tract infections accounted for the highest proportion (71.43%). A total of 36 strains of pathogens were identified, including 36.4% Gram-negative bacteria, 25.0% Gram-positive bacteria, and 5.6% fungi. The independent risk factors for nosocomial infections after kidney transplantation included the duration of surgery, sex, pre-transplant dialysis duration, and length of hospital stay (P<0.05). The predictive model was given by: logit(P) = -6.040 + 0.012×duration of surgery -1.639 ×sex (male=1; female=0) +0.050×length of hospital stay + 0.008×pre-transplant dialysis duration. Conclusion The incidence of nosocomial infections after kidney transplantation is relatively high. Enhanced monitoring and control measures should be implemented for patients with identified risk factors.
