近20年来，低温等离子体消毒灭菌技术迅速发展，展现出良好的应用前景。本文首先介绍了低温等离子体不同的产生方法与优缺点，其次综述了低温等离子体对细菌繁殖体、细菌芽孢、真菌、病毒及细菌和真菌毒素的杀灭效果，并从等离子体物理化学与细胞生物学两方面介绍了低温等离子体灭活微生物的机制，介绍了低温等离子体消毒灭菌技术的实际应用，包括对空气和医疗废水的消毒、医疗器械的消毒。最后针对当前研究现状和存在的问题做出了分析，展望了低温等离子体消毒灭菌技术应用于新型冠状病毒感染防治的可能性。

Objective To study the efficacy and mechanism of a new compound disinfection in killing different types of microorganisms. Methods The suspension quantitative bactericidal test method was used to study the bactericidal effect of the disinfectant; real-time fluorescence quantitative PCR and transmission electron microscopy were used to study the killing mechanism of the disinfectant on microorganisms. Results The disinfectant acted on Escherichia coli and Pseudomonas aeruginosa for 30 s and could kill them all; on Staphylococcus aureus for 30 s, the killing log value >5.00; on spores of Bacillus subtilis var niger for 60 min, the killing log value was 1.19. After Escherichia coli were trented by the compound disinfectant the expression levels of membrane protein genes LptD, LptE, OmpA, OmpC were slightly increased compared to the control group; the cell membrane of Escherichia coli and Staphylococcus aureus were damaged by the compound disinfectant. Conclusion This new compound disinfectant can effectively kill bacterial propagules mainly by destroying bacterial cell membrane and oxidizing intracellular substances to kill microorganisms.

Objective To study the corrosion of metals by chlorine dioxide, hydrogen peroxide, and peracetic acid. Methods Four kinds of chlorine dioxide, three kinds of hydrogen peroxide and three kinds of peracetic acid products were selected to study their corrosiveness to five kinds of metals of carbon steel, aluminum, copper, stainless steel and zinc sheet, and the corrosion rate was calculated. Results The liquid formulation of 300 mg/L chlorine dioxide exhibited severe corrosion on carbon steel sheets, copper sheets, aluminum sheets, and zinc sheets; Under the condition of 500 mg/L, chlorine dioxide solution still had little corrosion on stainless steel sheets. 3% hydrogen peroxide solution had little corrosion on carbon steel and stainless steel sheets, mild corrosion on copper and aluminum sheets, and severe corrosion on zinc sheets. 1.0 g/L peroxyacetic acid liquid preparation caused severe corrosion to carbon steel sheets, copper sheets, and zinc sheets, moderate corrosion to aluminum sheets, and minimal corrosion to stainless steel sheets. Conclusion Except for stainless steel, three types of peroxide disinfectants have corrosiveness to other four metals, hydrogen peroxide has lower corrosiveness, followed by chlorine dioxide, and peroxyacetic acid has the severest corrosivenes．

达芬奇机器人手术系统现已广泛应用于外科微创手术，与之配套的机器人手术复用器械的清洗、消毒、保养和管理工作日趋重要。由于达芬奇机器人手术复用器械具有价格昂贵（部分器械有限定使用寿命）、精密程度高、结构复杂和材质特殊等特点，如何安全、高效地完成机器人手术器械的清洗、消毒再处理工作，对医疗机构提出了更高的要求。本文阐述了目前国内外广泛使用的达芬奇机器人手术器械清洗、消毒、保养和管理方法，以及注意事项、新进展，以帮助各医疗机构管理人员和洗消人员根据自身特色、设备设施现状，因地制宜选择最适合的达芬奇机器人手术器械的清洗、消毒、保养和管理方法，更好地预防医院感染发生，确保医患安全。

Objective To observe the antibacterial activity and safety of a compound biological disinfectant containing antimicrobial peptide (AMP) and polyhexamethylene biguanide (PHMB) as main components. Methods Suspension quantitative bactericidal test and animal test methods were used to observe the antibacterial activity and safety of the compound biological disinfectant. Results When incubated with the compound biological disinfectant for 1 min, the average killing log value of the disinfectant for Staphylococcus aureus, Escherichia coil and Pseudomonas aeruginosa were >5.0, and that were >4.0 for Candida albicans. The LD₅₀ value of the disinfectant for mice was >5 000 mg / (kg • bw), which belonged to a practical non-toxic level. The original solution of the disinfectant had no irritating effect to the intact skin and mucous membranes of rabbits. Conclusion The compound biological disinfectant has good antibacterial effect and biological safety.

Objective To investigate the disinfection effect and influencing factors of LED ultraviolet disinfection device. Methods Using the carrier quantitative bactericidal test method, the bactericidal effect and influencing factors of LED ultraviolet disinfection device were observed. Results The LED ultraviolet disinfection device was equipped with 54 UV chips with wavelengths ranging from 270 to 280 nm. After 60 s of irradiation, Escherichia coli and Staphylococcus aureus on glass slide were completely killed; the killing rate of Candida albicans on glass slide could reach 99.99% after 30 s of irradiation; the killing rate of spores of Bacillus subtilis var niger on glass slide could reach 99.99% after 120 s of irradiation; the log value of inactivated infection titer of poliovirus on glass slide was 5.10 after 90 s of irradiation. Factors such as the carrier material, irradiation distance, radiation dose, organic matter, and moisture had impacts on the disinfection effect of LED ultraviolet disinfection device. Conclusion The LED ultraviolet disinfection device can effectively kill bacterial propagules, viruses, and bacterial spores, but its disinfection effect is influenced by many factors.

Objective To observe the disinfection effect of hydrogen peroxide on object surface and indoor air. Methods Field simulation and field evaluation test were applied to evaluate the disinfection effect of hydrogen peroxide on object surface and indoor air. Results The killing log valve was > 3.00 for Escherichia coli and Staphylococcus aureus standard strains with 35 g/L hydrogen peroxide for disinfection of 15 min. The average killing rate of natural bacteria on objects surface was above 90% with 105 g/L hydrogen peroxide for disinfection of 30 min at food production workshop，and the disinfection effect of natural bacteria of indoor air reached the qualified level by aerosol spraying for exposure of 30 min. Conclusion Spraying and aerosol spraying with hydrogen peroxide disinfectant are effective on object surface and indoor air disinfection.

Objective To observe the inactivation effect of chlorine disinfectants on human coronavirus, and to provide reference for contamination disinfection of novel coronavirus. Methods Suspension quantification method was used to observe the inactivation effect of chlorine disinfectants on human coronavirus HCoV-229E. Results Human coronavirus HCoV-229E in suspension was completely inactivated by chlorine-containing disinfectant containing 1 000, 750 and 500 mg/L available chlorine for 10, 20 and 30 min, respectively, at room temperature. The virus could not be completely inactivated by using a chlorine disinfectant with an effective chlorine content≤250 mg/L for 30 min. Conclusion Chlorine disinfectants has good inactivation effect on coronavirus, but the effective concentration and duration of action need to be ensured.

Objective To evaluate the long-acting disinfection effect of polyhexamethylene biguanide hydrochloride disinfectant, and to provide a reference basis for the establishment of evaluation method for the long-acting disinfection effect of disinfectants in China. Methods Referring to the evaluation method of British standard PAS 2424, the killing effect of disinfectant samples with different concentrations on bacterial propagules and pathogenic yeasts was observed. Results This disinfectant sample had the best long-acting disinfection effect on Escherichia coli, followed by the long-acting disinfection effect on Staphylococcus aureus and Pseudomonas aeruginosa, and the worst long-acting disinfection effect on Candida albicans, and the difference was statistically significant (P<0.05).Conclusion The polyhexamethylene biguanide hydrochloride disinfectant sample has a 24 h long-acting disinfection effect on Escherichia coli and Staphylococcus aureus.

Objective To study the disinfection effect and influencing factors of a photocatalytic disinfection machine on the air and surface of objects in an mist chamber under experimental conditions. Methods Air disinfection simulation field experiments and carrier quantitative killing test methods were used to observe the disinfection effect of a certain photocatalytic disinfection machine on laboratory air, fabric, and flat carrier. The method of comparing the number of bacterial colonies in each group using plate staining was used to explore whether there are disinfection factors produced in the air. Results The main disinfection factor of this photocatalytic disinfection machine was titanium dioxide, supplemented by metals such as rhodium and silver as photocatalysts. Under broad-spectrum ultraviolet irradiation and circulating wind conditions, the killing rate of Staphylococcus albus in air reached over 99.90% after 30 min of disinfection. Increasing the circulating air volume to 2 h, resulted in a 38.36% killing rate of Staphylococcus aureus on the fabric, but did not achieve the disinfection effect. The killing rates of Staphylococcus aureus on the agar plate after 4, 6, and 8 h of disinfection were 93.17%, 95.36%, and 97.06%, respectively. Conclusion The photocatalytic disinfection machine has a good disinfection effect on air in aerosol chamber, and the disinfection efficiency is positively correlated with the circulating air volume.

Objective To study the sustained antibacterial effects of three single chain quaternary ammonium salts against Candida albicans and to provide theoretical support for screening antibacterial products. Methods The carrier sustained antibacterial test method was used to compare and observe the sustained antibacterial effects of three kinds of quaternary ammonium salts: bromine, chlorine, and carbonate. Results Bromine, chlorine, and carbonate quaternary ammonium salts were all used with an active substance concentration of 2 000 mg/L, and their sustained antibacterial time against Candida albicans on the carrier reached 95, 95, and 59 d, respectively. Within the antibacterial validity period, the bacterial reduction rate was still maintained at ≥90%. The antibacterial effect of bromine and chlorine quaternary ammonium salts lasted longer than that of carbonate quaternary ammonium salts significantly. Conclusion All three kinds of quaternary ammonium salts have good sustained antibacterial effects, with bromine and chlorine quaternary ammonium salts having longer sustained antibacterial effects.

Objective To observe the weight change and occurrence of wet packs before and after pressure steam sterilization, so as to provide a basis for the judgment of wet packs. Methods A random block design was adopted to assemble the reusable orthopedic instruments to be sterilized in the orthopedics department of a hospital from August to October 2022. They were randomly packed with cotton cloth, non-woven fabrics, hard containers or new textile materials in accordance with the specifications, then the packs were sterilized by pressure steam. With the same procedure, weight of packs before sterilization and within 5 min after sterilization were weighed up. and wet packs were checked for after cooling for 30 min. All packs were repeatedly sterilized for 40 times, and the incidence rate of wet pack cases and the weight reduction rate after sterilization were calculated. Results There is no statistically significant difference among the four types of packaging materials in the incidence rate of wet pack cases after sterilization (χ²=3.490，P=0.322). Wet packs occurred in 26 cases after 160 sterilization operations, There were 13 cases with weight increasing and the weight increase rate was >0.2% in a case, while the weight of non-wet packages did not increase. The weight reduction rates of wet packs after sterilization in four types of materials packages were all smaller than those of non-wet packs (P<0.05). Conclusion There is no significant difference in the wet pack incidence rate of four packaging materials. Using the weight increase of the package after sterilization as a wet pack criterion still needs further exploration and verification.

Objective To evaluate the disinfectant efficacy of compound quaternary ammonium salt wipes. Methods Disinfectant wipes were prepared by impregnation with a solution containing 2 060 mg/L of benzalkonium chloride, which concentration of the squeezed solution of wipes was 1 800 mg/L. The disinfection effect of the wipe was evaluated by suspension quantitative germicidal test, carrier quantitative germicidal test, wipes carrier quantitative germicidal test and field disinfection test. Results For E.coli, S. aureus and P.aeruginosa in suspension incubated with the squeezed solution of wipes for 1 min, the killing logarithmic(KL) values were >5.00 and that of C.albicans was >4.00. For E.coli, S. aureus and P.aeruginosa on the cloth carrier, when incubated with the disinfectant for 5 min, the KL values were 3.18, 3.28 and 3.12, respectively, and that of C. albicans was 1.22 with 10 min incubation. For E.coli, S. aureus and P.aeruginosa in tryptone physiology solution plus 3% organic substance, the KL values were 3.58, 3.86 and 3.42, respectively, and that of C. albicans was 2.89 when incubated for 10 min. For E. coli, S.aureus and P. aeruginosa in phosphate buffered saline, the mean KL values were 3.92, 5.30 and 3.80, respectively when incubated for 1 min, and that of C. albicans was 3.22 when incutated for 3 min. The KL values of wipes against natural bacteria on surface of desk were all >1.00. Conclusion There are significant differences in the results of different experimental methods on disinfectant efficacy evaluation.

Objective To observe the disinfection effect and toxicity of the new high-efficiency ultraviolet multi-directional mobile disinfection chamber. Methods The disinfection effect and toxicological safety of the disinfection chamber were evaluated using virus carrier quantitative killing test, air disinfection simulation field test, air disinfection field test, and acute inhalation toxicity test. The virus killing effect on slide carriers at different locations, the bacterial content before and after air disinfection, and the manifestations and deaths of acute inhalation toxicity of mice were observed. Results The logarithm of the inactivation of enterovirus EV71 and poliovirus typeⅠvaccine strain（PV-Ⅰ） was > 4.00, and the killing rate of Staphylococcus albicans was 99.99%. The death rate of natural bacteria in the air was 99.07%, and no poisoning symptoms appeared in the inhalation toxicity test. Conclusion The disinfection chamber has a significant disinfection effect on microorganisms, and it is safe under the experiment condition.

Objective To observe the effect of a mobile air purification and disinfection equipment on air disinfection and purification in operating room. Methods 4 clean operating rooms were selected in an orthopedic hospital, which we set as central air-conditioning purification system group, purification and disinfection equipment group, central air-conditioning purification system + purification and disinfection equipment group, and baseline group. After indoor cleaning and equipment operation for 30 min, the indoor air dust particle count and total bacterial count were detected using the air microbial sampler and the plate sedimentation method, respectively. Results Running the mobile air purification and disinfection equipment alone, or running the central air-conditioning purification system and air purification and disinfection equipment simultaneously for 30 min, it could significantly reduce the number of ≥0.5 µm dust particles, and the cleanliness of the operating room could be increased from level 8 to level 7. During the operation of each group of equipment, total bacterial count in the operating room was significantly lower than the baseline, reaching the standard of grade clean operating room. Conclusion This air purification and disinfection equipment can effectively reduce the number of Ⅳdust particles and total bacterial count in the operating room air, and has a good air purification and disinfection effect.

Objective To observe the disinfection efficacy and corrosiveness to metals of a compact catalytic ozone generator on air and object surface in enclosed spaces. Methods Quantitative carrier tests and on-site tests were carried out to observe the disinfection effect and metal corrosion of an ozone disinfection device. Results The killing rate of the ozone disinfection device on Staphylococcus albus in air was 99.99% with 10 mg/m³ ozone for 30 min. For fabric carriers acted with 10 mg/m³ ozone, the killing logarithmic values were >3.00 against Escherichia coli for 40 min and against Staphylococcus aureus for 120 min. For Bacillus subtilis var. niger spores on the paper carrier, the killing logarithmic values were >3.00 with 30 mg/m³ ozone for 3 h. After being treated with ozone 20 mg/m³ for 20 cycles, totaling 60 h, minimal corrosion was observed on stainless steel, carbon steel, copper, and aluminum. Conclusion The ozone disinfection device can be used for air and object surface disinfection at room temperature, achieving highly effective disinfection. It can achieve efficient disinfection of paper bacterial carriers and has little corrosive effect on metals.

Objective To study the antibacterial performance of a copper-based nanomaterial and the factors affecting its antibacterial effect, and to explore the the possibility of its practical application. Methods The film pasting method was used to test the antibacterial performance of the copper-based nanomaterial against Staphylococcus aureus and Escherichia coli, and the effects of organic interference, temperature and humidity changes, chemical neutralization and other conditions on the antibacterial performance of the material were studied. Results The killing logarithmic values of Staphylococcus aureus and Escherichia coli on the surface of the copper-based nanomaterial were >6.71 and >6.37 respectively when the nanomaterial was treated at 37℃ and a relative humidity of 90% humidity for 1 h. Using Staphylococcus aureus as the indicator bacterium, the killing logarithmic value decreased to 5.87 when 3% BSA was added; under the conditions of reducing temperature 20℃，90% and humidity 37℃，30%, the killing logarithmic values decreased to 2.78 and 3.59, respectively; after using D/E neutralizer, the killing logarithmic value decreased to 4.15.Conclusion This copper-based nanomaterial has good antibacterial performance, but organic interference and changes in environmental temperature and humidity can affect its bactericidal effect, and the use of neutralizers during evaluation will also directly affect the test results.

Objective To investigate the appropriate upstream aerosol concentration in the integrity test of the high efficiency particulate air （HEPA） filter of the biosafety cabinet. Methods According to the method of YY 0569—20116.3.2 of Class II biological safety cabinet, different concentration of PAO aerosol ranged from 11-91 μg/L were applied to the upwind side of the HEPA filter of a biological safety cabinet, and the leakage rates were detected downstream, and the correlation between leakage rate and upstream aerosol concentration was studied. Results When the upstream aerosol concentrations ranged from 11-50 μg/L, the leakage rates were negatively correlated with the upstream aerosol concentration, and the leakage rate of the supply air HEPA filter ranged from 0.000 1%-0.002 1%, and the leakage rate of the exhaust HEPA filter ranged from 0.000 1%-0.005 3%. At the upstream aerosol concentration > 50 μg/L, the maximum leak rate no longer changed. Conclusion The upstream aerosol concentration of 10-30 μg/L is more appropriate in the leakage detection process of HEPA filter in biological safety cabinet.

Objective To observe the disinfection efficacy of a plasma disinfection module on object surfaces, and to provide scientific basis for practical disinfection application. Methods The disinfection efficacy of a certain plasma disinfection module on object surfaces was experimentally observed with simulated field disinfection test method. Results When the plasma generator module was irradiated for 10 min from the vertical height of 1.5 cm above the surface, the mean killing logarithm values of Candida albicans and Bacillus subtilis var. niger spores on the surface were 2.28 and 1.90, respectively. After irradiation and disinfection for 2 min, the logarithm killing values of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa on the surfaces of objects were all > 3.00. Conclusion The plasma generator module has a good killing effect on vegetative forms of bacteria, and poor killing effect on fungi and bacterial spores when irradiated at colse range.

2022年国家卫生健康委员会医院管理研究所建立了消毒供应质量控制指标体系，运用3个级别指标从不同管理维度对复用医疗器械再处理各流程环节进行质量控制，并取得了良好效果。本文以案例介绍、问题分析和处理措施为框架，介绍了某医院消毒供应中心在设备设施定期维护、器械清洗、器械包装、包外湿包和包内湿包控制方面有效落实该质量控制指标体系的实践经验，为促进消毒供应质量控制工作更加科学合理提供参考。

222 nm紫外线通过破坏DNA有效杀灭微生物；与254 nm紫外线不同之处在于，222 nm紫外线能够被蛋白质吸收，在辐照到DNA前已被蛋白质耗尽，从而避免了对皮肤和眼睛造成危害。然而，222 nm紫外线消毒产物，如蛋白质变性和环丁烷嘧啶二聚体（CPD）增加等原始证据未见有报道。在充分阐明消杀原理前，使用222 nm紫外线进行消毒仍需要遵守相关规范，以确保消毒的安全性和有效性。

目的 研究消毒供应中心（CSSD）应用持续质量改进循环管理模式（FOCUS-PDCA）对医院感染管理的影响。方法 以2020年6月医院CSSD实施FOCUS-PDCA管理为界，比较实施前后CSSD工作人员工作规范性、安全事故发生率、物品消毒质量和服务满意度。结果 FOCUS-PDCA实施后，CSSD护理人员回收清洗、包装、灭菌及发放等工作规范性得分均较实施前提高，人员划伤、压伤等安全事故发生率较实施前降低，消毒物品循环时间减少，物品丢失及器械导致的感染率降低，物品清洁达标率、消毒达标率、灭菌达标率及包装达标率上升，各科室对CSSD的工作满意度上升，差异均具有统计学意义（P<0.05）。结论 开展FOCUS-PDCA管理可有效提高CSSD工作人员工作质量，保障医疗器械清洁、消毒及灭菌质量。

聚维酮碘（povidone iodine, PVP-I）是一种广谱、高效的杀菌剂，已有60多年的应用史。本文综述了PVP-I的结构特性、杀灭病毒机制、抗药性、安全性、常用剂型等，并总结了近两年临床实验结果，表明通过口腔含漱、鼻腔冲洗等方式，PVP-I液体制剂能显著降低呼吸道病毒载量，减缓和控制病毒传播，缩短康复周期。

Objective To explore the distribution of pathogens and risk factors of neonatal hospital infections. Methods A retrospective survey was conducted on 1 569 newborns in the neonatal ward of a certain hospital from January 2021 to December 2022. Hospital clinical medical records and pathogen isolation and identification results of blood, sputum and umbilical secretions were collected, and the univariate analysis and multivariate logistic regression analysis were used to identify the risk factors for nosocomial infection in newborns. Results The incidence rate of nosocomial infection was 4.91%, mainly respiratory tract （50.65%）, followed by urinary tract infection. A total of 85 pathogenic strains were detected in 77 children with nosocomial infection, mainly Gram-negative bacteria（60.2%）, among which Escherichia coli had the highest proportion （47.05%）. The proportion of Staphylococcus hemolyticus in Gram positive bacteria was the highest （9.41%）. Multivariate logistic regression analysis showed that gestational age < 37 weeks, having three or more underlying diseases, hospital stay of≥7 d, amniotic fluid contamination, mechanical ventilation, feeding intolerance, mechanical ventilation and feeding intolerance were independent risk factors for neonatal nosocomial infection. Conclusions Neonatal nosocomial infection is mainly respiratory tract infection, and pathogenic bacteria are common with Gram-negative bacteria. Effective prevention and control measures should be taken especially for high risk factors to reduce the nosocomial infection rate.

Objective To observe the bacteriostasis potency of 13 individual antimicrobial agents and 6 compound liquids against Burkholderia cepacia. Methods The tube suspension method was used to monitor the survival of Burkholderia cepacia in various individual antimicrobial agents and compound liquids. Results Among the 13 commonly used individidual antimicrobial agents, a 2.0% solution of 1, 2-hexanediol and a 0.08% dodecyl dimethyl benzyl ammonium chloride incubating for 0.5 h, 0.15% methylparaben inccubating for 24 h, and 0.10% ethylparaben incubating for 1 h, the killing log value for Burkholderia cepacia decreased by ≥5.0, and the killing log values of other individual components were ≤ 3.0 after incubationg for 28 d. The number of bacteria in the test system of 0.15% ethylparaben, 0.08% and 0.12% cetylpyridine chloride could still increase when the number of bacteria in the system < 10 cfu/mL. The bacteriostasis efficacy of 0.05% caprylhydroxamic acid + 0.15% p-hydroxyacetophenone and 0.13% dodecyl dimethyl benzyl ammonium chloride + 0.06% cetylpyridine chloride did not meet the ISO 11930 “Evaluation of the antimicrobial protection of a cosmetic product”requirements, and the bacteriostasis efficacy of the other four compounds met the requirements. Conclusion The bacteriostasis potency of individual antimicrobial agents against Burkholderia cepacia can be enhanced by specific compounding.

Objective To investigate the nosocomial infection, detection status and drug resistance of carbapenem-resistant Acinetobacter baumannii （CRAB） in intensive care units （ICU） and general wards. Methods The clinical data and microbial information of inpatients from January 2016 to December 2019 were retrospectively investigated, and the characteristics of CRAB infection and drug resistance in the two groups were analyzed. Results There were 305 cases of CRAB nosocomial infections, including 250 cases （1.69%） in ICU and 55 cases （0.02%） in general wards, and the infection sites were mainly lower respiratory tract. In ICU group, the incidence of CRAB infection cases in ventilator-associated pneumonia and bloodstream infection was higher, and the detection rate of CRAB infection was higher, showing a downward trend year by year. The drug resistance rate of CRAB to tigecycline was the lowest, followed by amikacin, and the drug resistance rate of CRAB to other commonly used antibiotics was more than 90%. The drug resistance rate of CRAB to tigecycline and tobramycin in general ward was higher than that in ICU. The drug resistance rate of carbapenem sensitive Acinetobacter baumannii to most commonly used antibiotics was mostly less than 10%. Conclusion There are some differences in the infection sites of CRAB, detection rate and drug resistance between ICU and general ward. We should strengthen the monitoring of CRAB infection, use drugs scientifically and rationally, and effectively control infection and slow down transmission.

Objective To measure the content changes of different brands of peracetic acid disinfectants under different conditions of use, and to provide data for stability test of peracetic acid. Methods The content of 9 brands of peracetic acid disinfectant after opening the bottle once, daily opening the bottle for 1 h, daily dilution, or daily use in an endoscope cleaning-disinfection machine were measured. Moreover, the peracetic acid content in 3 brands of peracetic acid disinfectant was determined after extended use to 28 d. Results The peracetic acid disinfectant was tested after opening the bottle once, daily opening the bottle for 1 h, or daily dilution, the peracetic acid concentrations in 2-3 of the 9 brands of disinfectants were reduced to less than 1.00 g/L. After daily use in an endoscope cleaning-disinfection machine, the reduction rate of peracetic acid was higher than that of other forms of use. In this experiment, a brand of peracetic acid disinfectant had good stability, and the content of peracetic acid was still >1.50 g/L after 28 d of use. Conclusion The endoscope cleaning-disinfection machine is more suitable for evaluating the stability of peracetic acid pairs after continuous use. Moreover, the stability of peracetic acid in different brands of disinfectants varies greatly, and some disinfectant may not be able to maintain a qualified effective concentration of peracetic acid after continuous use.

Objective To investigate the current situation of disinfection quality in nursery institutions in Shandong Province, so as to identify problems and put forward suggestions and countermeasures. Methods A stratified random sampling method was used to select 434 nursery institutions in 15 cities in Shandong Province, and the indoor air, object surfaces, staff’s hands and tableware were detected. Results From 2020 to 2022, the total qualified rate of disinfection in nursery institutions in Shandong Province was 91.50%; the qualified rates for different years were 90.10%, 91.31%, and 92.38%, respectively, and the difference was statistically significant (x²=6.01, P=0.049). There was no significant difference in the overall qualified rate of disinfection in urban nursery institutions of different grades (x²=3.49, P=0.17). There was significant difference in the qualified rate of disinfection among different monitoring items (x²=37.95, P<0.01), and the qualified rate of tableware was the highest. Conclusion The disinfection quality of nursery institutions in Shandong Province is generally good, but the qualified rate of some items such as indoor air and object surface disinfection is low. It should be targeted to improve the disinfection quality of weak links, and keep good disinfection quality of staff’s hands and tableware.

Objective To study the disinfection effect of a plasma air disinfection machine on indoor air under occupied (dynamic) and unmanned (static) conditions. Methods A plasma air disinfection machine was used in a kindergarten classroom to disinfect indoor air under occupied and unmanned conditions, and the planktonic bacteria, settling bacteria, particles and microorganisms load in indoor air before and after disinfection were compared to comprehensively assess the disinfection effect of the plasma. Results In unmanned room, the extinction rate of indoor air was more than 90% after 60 min of disinfection; in occupied room, the extinction rate of indoor air was still more than 50% despite continuous air pollution due to human activities. Regardless of whether there were people indoors or not, the settling bacteria, particles and microorganisms load in air were decreased after disinfection. Conclusion The plasma air disinfection machine can effectively eliminated bacteria and particles in air, and can be used in occupied room. It provides an effective disinfection method for preventing the indoor spread of airborne diseases.

Objective To investigate the cleaning, disinfection and management of loaned medical instruments and implants in hospitals of nationwide, so as to provide a basis for standardized management. Methods A self-designed questionnaire was used to investigate the cleaning, disinfection and management of loaned medical instruments and implants after use in 209 hospitals in China from March to June 2022, and the influencing factors were analyzed. Results A total of 215 questionnaires were distributed, and the effective response rate was 97.21%. Among the 209 hospitals, 79.4% of hospitals cleaned and disinfected all the instruments and implants after using, and 40.7% of hospitals cleaned and disinfected instruments by central sterile supply department. 58.9% of hospitals set up special posts in the process, and full traceability was realized in 63.2% hospitals. Compared to the cleaning, disinfection and management of loaned medical devices and implants before use, various levels of hospitals did not perform enough after their use. Conclusion The cleaning, disinfection and management of loaned medical instruments and implants after use in hospitals at all levels are not standardized, and there are issues such as incomplete systems and regulations, non-standard instruments treatment, incomplete information, and unreasonable personnel arrangements. All departments of the hospital should actively take targeted measures for improvement.

分析2020年3月31日—11月30日期间某医院消毒供应室2台过氧化氢低温等离子灭菌器中断原因。100S灭菌859锅次，中断9锅次，中断率为1.01%；100NX灭菌1 525锅次，中断7锅次，中断率为0.46%。对于100S老设备应关注设备配件的老化问题及时更新加强维护使之保持良好性能，100NX灭菌中断原因中可控因素占85.7%，通过干预可以避免。

Objective To understand the current situation of hospital management of disinfectants in Zhejiang province, and to evaluate the effectiveness of improving the management of disinfectants in a hospital's central sterile supple department (CSSD), in order to provide reference for improving the quality of hospital disinfection management. Methods A questionnaire survey was conducted on the knowledge background, nature of organization, management attribution, education and training, and personnel turnover of disinfection personnel in 87 hospitals in the province. Based on the survey results, we improved the CSSD disinfection management of a certain hospital, compared the changes in disinfection monitoring indicators before and after the improvement of management quality, and strengthened the theoretical and operational levels of disinfectants before and after training. Results Only 21.83% of the 371 disinfection workers surveyed had bachelor degree or above, 46.90% had informal establishment, and 1.89% had lost their staff within one year. Disinfectors in 55 hospitals were managed by non-nursing departments, and the training and assessment of disinfectors in 76 hospitals were handled by nursing departments. After the improvement of management quality, the indicators of CSSD equipment bar code posting error rate, equipment bar code missing brush rate, wet package rate of sterilized goods, equipment backwashing rate and sterile goods distribution error rate in a hospital all reached the qualified target value, and the theoretical and operational assessment scores of disinfectors after intensive training were higher than those before training. Conclusion Targeted and planned management and training of disinfectors in hospitals will help to improve the ability of disinfectors, stabilize the team of disinfectors and meet the development needs of CSSD in hospitals.

Objective To study disinfectant resistance and select related genes of Staphylococcus aureus （S. aureus）from different sources. Methods The gene detection and the quantitative germicidal test were used to detect the resistance of S. aureus to common disinfectants and related genes. Results The killing logarithm values of 75% ethanol, 2 000 mg/L quaternary ammonium salt, 5 000 mg/L polyhexamethylene biguanide to S. aureus with 1 min contact time were all >5.00. The average killing logarithm values of 1 000 mg/L effective chlorine to 4 clinical strains （No.Y7，Y19，Y24，Y13）with 1 min were all > 5.00. The average killing logarithm values of 3 000 mg/L trichloro hydroxydiphenyl ether against 4 clinical strains （No.Y7，Y19，Y24，Y13） with 3 min were all <5.00. Drug resistance gene ermA, TetM, mecA, acc-aph and disinfectant resistance gene qacA were detected in 3 clinical strains (No.Y7，Y19，Y24). Conclusion There are different in the resistance of S. aureus to disinfectants between foodborne and hospital sources. Drug resistance genes and disinfectant resistance genes are detected in some clinical strains.

Objective To investigate the efficacy and safety of polyhexamethylene biguanide (PHMB) as a fruit and vegetable disinfectant. Methods According to the technical requirements of hygienic safety evaluation of disinfected products, the physical and chemical properties of PHMB were determined, such as pH value, heavy metal content, PHMB content and stability. The disinfection effects were evaluated by tests of the identification of neutralizers, microbial killing effect, and on-site test of object surface disinfection. The toxicological safety were evaluated by tests of acute oral toxicity, mutagenicity, and one-time intact skin irritation. Results At 25℃, the pH value of the disinfectant was 7.08. The content of As was <0.01 mg/kg, Hg was <0.002 mg/kg, Pb was <1.5 mg/kg. The content of PHMB was 0.497 g/kg. After being stored at 37℃ for 3 months, the content of PHMB decreased to 0.492 g/kg. Decrease rate was 1.27% (w/w). Incubated for 5 min, the killing logarithms(KL) of E.coli in suspension were all>5.00, and the average KL for natural bacteria on cucumber surface were >1.00. The acute oral toxicity of the disinfectant was actually non-toxic, and the micronucleus test of mouse bone marrow polychromatic red blood cells had no micronucleus effect, and a complete skin irritation test was non-irritating. Conclusion The disinfectant has good disinfection effect, stability and safety for fruit and vegetable disinfection.

Objective To explore the safety of drying methods employed in the re-treatment process of digestive endoscopes. Methods The safety of drying method during reprocessing in a hospital were evaluated by using instrument method and microbial culture method. Results A number of water droplets in the biopsy channel of endoscopes in manual clean group was more than that in automatic clean machine group. In experimental group, endoscopes were dried using an air gun until no moisture remained, while in the control group the air gun was utilized for a duration of 30 s. Biological testing with 4 h after drying revealed that both methods met all required standards.The qualified rate of the biological detection was 95% for both methods 8 hours post-treatment. Conclusion The air gun drying for 30 s can meet the requirements, and the drying effect with the automatic cleaning process is better than with manual cleaning.

Objective To explore the feasibility of using phage Phi-X174 as indicator virus for evaluating the effect of air virus disinfection. Methods Phage Phi-X174 was nebulised into the air disinfection chamber. Referring to the requirements for the microbial counts of air indicators in China's air disinfection effect evaluation standards, the key parameters such as sampling solution, phage suspension titre, nebulisation time, nebulisation volume, etc were investigated to determine the generation mode and sampling method of phage aerosols, and the natural settling rates of phage aerosols at different time points were analyzed. Using the preliminarily established method, the killing effect of a photocatalytic disinfection technology on phage in air was evaluated. Results SM buffer was more efficient than PBS for phage Phi-X174 collection. When 1.5 mL of phage suspension with a titre of 3×10⁸ pfu/mL was nebulized, the average phage concentration in the air disinfection chamber was 4.25×10⁶ pfu/m³ with good reproducibility. The average natural settling rates of phage aerosols at 15 min, 30 min, 45 min and 60 min were 28.40%, 51.79%, 68.61% and 79.58%, respectively. The photocatalytic air disinfection technology was applied with high airflow for 45 min or low airflow for 60 min, and the average killing rate of phage could reach 99.9%. Conclusion Aerosol sampling with SM buffer and 1.5 mL of phage suspension with a titre of 3×10⁸ pfu/mL as the nebulisation generating solution can achieve relatively stable concentration of phage aerosols in air for a certain period of time, with better test reproducibility, and higher sampling efficiency, etc., which is basically in line with the requirements of air indicator microorganisms.

Objective To explore the disinfection effect of xenon light transfer chamber in public health event isolation places or infectious disease isolation wards when contaminated items were transferred from contaminated areas to clean areas. Methods The carrier quantitative sterilization test method was used to compare the disinfection effect of xenon light transfer chambers on different concentrations of pathogenic microorganisms for different times. Results When the glass bacterial plates of Escherichia coli were disinfected by the xenon light transfer chamber, the killing log values of bacterial plates with 10³ cfu/piece disinfected for 1~5 min and bacterial plates with 10⁴, 10⁵ and 10⁶ cfu/piece disinfected for 3~5 min could all achieve >3, while the killing log values of bacterial plates with 10⁴, 10⁵ and 10⁶ cfu/piece disinfected for 1~2 min were all <3. When the glass bacterial plates of Staphylococcus aureus were disinfected by the xenon light transfer chamber, the killing log values of bacterial plates with 10³, 10⁴, 10⁵, and 10⁶ cfu/piece disinfected for 1~5 min could all reach >3. When the glass bacterial plates of spores of Bacillus subtilis var niger and Candida albicans were disinfected by the xenon light transfer chamber, the killing log values of bacterial plates with 10³, 10⁴, 10⁵, and 10⁶ cfu/piece disinfected for 1~5 minutes were all <3. Conclusion The xenon light transfer chamber can achieve non-contact, automated and effective disinfection, with short-time consumption and environmental friendliness, and can effectively reduce the load of pathogenic microorganisms on the surface of objects. During application, disinfection procedure should be determined according to the type and load concentration of contaminated pathogenic microorganisms to ensure effective disinfection effects.

Objective To study the residual of ethylene oxide and 2-chloroethanol in medical devices. Methods Thirteen kinds of polymer materials commonly used in medical devices were sterilized, and ethylene oxide and 2-chloroethanol residues were tested by gas chromatography without analysis.After 3, 5 and 7 days of analysis, the effects of ethylene oxide residue and resolution rate, as well as the effects of extraction temperature, time and chloride ion concentration on the detection of 2-chloroethanol were detected. Results No 2-chloroethanol was detected in any of the 13 materials after sterilization. Acrylonitrile-styrene-butadiene copolymer (ABS), polyurethane and polyvinyl chloride ethylene oxide residues were 632.27, 577.66 and 524.53 μg/g, respectively, while silicone rubber and fluoroplastics had fewer residues of 5.34 and 72.73 μg/g, respectively. There was a significant difference in the resolution rate of different materials, and the resolution rate of fluoroplastics and polyetheramide block copolymers was the fastest, with 100.00% and 98.34%, respectively. The concentration of chloride ions had an effect on the detection of 2-chloroethanol. Conclusion Medical device companies should conduct specific analysis of the selected materials at the beginning of product design, and reduce ethylene oxide residues by controlling sterilization and analysis conditions if necessary, while the control of 2-chloroethanol residues may not be necessary.

Objective To observe the disinfection effect of a double-chain quaternary ammonium salt disinfectant in a low-temperature environment of -40℃, and to provide reference for the application of low-temperature disinfection. Methods Carrier quantitative bactericidal test and on-site disinfection test methods were used to observe the disinfection effect of the double-chain quaternary ammonium salt disinfectant on environmental surfaces under low temperature conditions. Results The content of stock solution of the double-chain quaternary ammonium salt disinfectant was 37 g/L, and the pH value was 5.03. This disinfectant has no precipitation or crystallization after being placed at -40℃ for >8 h. In a low-temperature cold storage at -40℃, the stock solution was sprayed for 30 min, and the killing log values of Escherichia coli and Staphylococcus aureus on the fabric samples were both >3.00; the stock solution was sprayed at 10 mL/m³ for 60 min, and the killing log values of Escherichia coli and Staphylococcus aureus on the glass surface were both >3.00. The stock solution of the disinfectant was non-irritating to the intact skin of New Zealand rabbits. The acute oral toxicity test on mice was non-toxic and had no micronucleogenic effect on mice. Conclusion This double-chain quaternary ammonium salt disinfectant can kill Escherichia coli and Staphylococcus aureus on environmental surfaces at low temperature of -40℃, and is an actual non-toxic substance.

Objective To observe the effect of time and temperature on the concentration of available chlorine in a certain 84 disinfectant during storage. Methods The iodine assay was used to detect the changes of available chlorine concentration of a commercial 84 disinfectant after 12 weeks at 4, 10, 20, 30 and 37℃. The degradation rate was calculated and the high fitting curve of the disinfectant was plotted. Results After 12 weeks storage at 4, 10, 20, 30 and 37℃, the available chlorine concentrations of 84 disinfectant with initial available chlorine content of 72.31 g/L decreased to 59.90, 58.13, 55.60, 45.72 and 38.63 g/L, respectively. The degradation rates of available chlorine were 17.16%, 19.61%, 23.10%, 36.77% and 49.34%, respectively. The degradation rate of available chlorine in the first 5 weeks was significantly higher than that in the last 7 weeks at 5 storage temperatures. When the storage temperature was below 30℃, the available chlorine content was stable after 5 weeks. Conclusion The higher the temperature, the faster decrease of the effective chlorine concentration. At low concentration, decrease rate is relative slow, and the disinfectant is more stable.