The relative effectiveness of commonly used disinfectants in inactivation of echovirus 11.

Echovirus 11 in the presence of fetal calf serum was exposed to six commonly used disinfectants for times of 10, 20 and 30 s. At the end of such exposure times, skim milk neutralized disinfectant activity and residual virus was assayed using the plaque technique. The six disinfectants studied were Javex, sodium hydroxide, ethanol, Wescodyne, One Stroke Ves-Phene, and Sonacide. Although 0.25% (w/v) sodium hydroxide and 95% (v/v) ethanol were equally virucidal and significantly more so than the other four disinfectants, causing 10(6) reduction in 20 s, they may not be practical to use in many instances. Javex at a dilution of 1/50 (1200 parts/10(6) chlorine) proved to be virucidal causing 10(3.5) reduction of echovirus 11 in 30 s. Wescodyne (1/50) and undiluted Sonacide were relatively ineffective causing 10 reduction or less of echovirus 11 in 30 s. One Stroke Ves-Phene (1/50) was ineffective causing no significant inactivation in 30 s.     

The relative effectiveness of commonly used disinfectants in inactivation of coxsackievirus B5.

Coxsackievirus B5 in the presence of fetal calf serum was exposed to six commonly used disinfectants for times of 10, 20 and 30 s. At the end of exposure times skim milk neutralized the disinfectant activity, with residual virus assayed by the plaque technique. The six disinfectants considered were Javex, sodium hydroxide, ethanol, Wescodyne, One Stroke Ves-Phene and Sonacide. Although 95% (v/v) ethanol was significantly more virucidal than dilutions of the other five disinfectants tested causing a 10(6) reduction in 20 s, it may not be practical to use in many instances. Next to 95% (v/v) ethanol, 1/75 (800 parts/10(6) Javex, 0.25% (w/v) sodium hydroxide and 1/200 Wescodyne were the most effective virucides. These disinfectants were equal in effectiveness causing a 10(5) reduction of coxsackievirus B5 in 30 s. Of these three disinfectants Javex is the most practical to use since sodium hydoroxide is caustic and Wescodyne is selective in its virucidal action. Undiluted Sonacide was a less effective virucide causing a less than 10-fold reduction of coxsackievirus B5 in 30 s. A 1/50 dilution of One Stroke Ves-Phene was the least effective virucide tested since it did not significantly inactivate coxsackievirus B5 in 30 s.     

The use of bacteriophage MS2 as a model system to evaluate virucidal hand disinfectants.

A model system which would closely reflect the resistance of poliovirus but could be easily performed in any microbiology laboratory would offer considerable advantages for rapidly screening hand decontamination products. The use of the bacteriophage MS2 as a simple model for virucidal testing has been evaluated. In suspension tests the sensitivity of MS2 to alcohols, organic acids and alkalis generally reflected that observed in studies using poliovirus. MS2 could be applied and recovered from the hands of volunteers with high efficiency. Furthermore MS2 proved to be a suitable replacement for Escherichia coli in a standard hand-decontamination test.     

连续消毒对水中指标病毒—f2噬菌体抗力影响探讨

Under defined conditions, E. coli bacteriophage f2 was subject to repeated disinfection by chlorine 10 times. The survival bacteriophage f2 was compared with its original strain in resistance to chlorine. Experimental results showed that bacteriophage f2 increased its resistance after chlorine disinfection. The increased resistance varied under different conditions. The higher the pH, the greater the increased resistance. The survival bacteriophage f2 maintained its increased resistance though it was passaged 10 times in nutrient broth. The reason for the increased resistance of bacteriophage f2 after chlorine disinfection was probably the chlorine-induced mutation or spontaneous chlorine-resistant mutation.     

Inactivation of f2 coliphage in municipal effluent by the use of various disinfectants.

Bromine chloride, chlorine and peracetic acid inactivated f2 coliphages in effluent but in order to achieve 99.99% inactivation the three disinfectants were required at about 1, 10 and 100 mg/l respectively. The activity of chlorine was halved by the presence of added organic matter, whereas bromine chloride and peracetic acid were very little affected. When a second successive dose of virus was added to the reaction mixture, the virus was inactivated only by peracetic acid despite the fact that in the chlorine-treated effluent residual chlorine was detected. The addition of a second dose of disinfectant inactivated residual virus in the same way as the first dose.     

Mechanism of inactivation of bacteriophage deltaA containing single-stranded DNA by ascorbic acid.

The mechanism of inactivation of a single-stranded DNA phage, deltaA of Escherichia coli, by AsA was investigated as a part of the study on the mechanism of inactivation of viruses by AsA. Bubbling air or oxygen gas through the reaction mixture, and the addition of oxidizing agents or transition metals into the reaction mixture enhanced the inactivation of the phage by AsA. In contrast, nitrogen gas bubling, and the addition of reducing agents, chelating agents or radical scavengers prevented inactivation. The rate of inactivation was faster in the AsA solution preincubated for several minutes than in the freshly prepared AsA solution. DAsA, an oxidized form of AsA, demonstrated little effect on the activity of the phage. Concentrations of hydrogen peroxide which were theoretically produced by the autoxidation of AsA had no effect on the phage. The results indicated that the free radical intermediates produced during the course of the autoxidation of AsA participated in the inactivation. The radicals attacked the DNA of the phage to introduce strand scissions in the DNA, which might be mainly responsible for the inactivation.     

淋病奈瑟菌对化学消毒剂的抗力研究

目的了解淋病奈瑟菌对化学消毒剂的抗力。方法采用悬液定量杀菌试验，观察不同菌株对化学消毒剂的抗力。选择抗力较高的菌株，观察在不同浓度有机干扰物存在时对消毒效果的影响。结果含有效氯100mg／L消毒剂对淋病奈瑟菌标准菌株29105及临床分离株分别作用4min，其杀灭对数均值分别为5．50和7．11；含有效碘50mg/L消毒剂对上述两菌分别作用4min，其杀灭对数均值分别为5．01和5．32。达到消毒要求所需的消毒剂浓度，在3．0％牛血清蛋白存在时，是含PBS菌悬液的5-6倍。结论淋病奈瑟菌标准菌株29105对化学消毒剂的抗力略强于临床分离淋病奈瑟菌株。淋病奈瑟菌对化学消毒剂的抗力随有机干扰物浓度增高而增强。     

两种内镜消毒剂相关性能比较

目的比较一元过氧乙酸消毒剂II型和含氯消毒剂的相关性能,为临床消毒剂的选择提供参考。方法本研究按照相关标准规范通过现场消毒试验方法,对一元过氧乙酸消毒剂II型和含氯消毒剂消毒后胃镜进行采样,比较分析两种消毒剂的消毒效果并进行稳定性及腐蚀性研究。结果一元过氧乙酸消毒剂II型对胃镜高水平消毒的合格率(98.5%)高于含氯消毒剂(88.9%),但有效成分含量的下降率低于含氯消毒剂(P<0.05)。两种消毒剂对不锈钢无腐蚀性,对碳钢、铝和铜均为轻度腐蚀。结论一元过氧乙酸消毒剂II型能达到胃镜高水平消毒标准且稳定性高,综合性能优于含氯消毒剂。     

铜绿假单胞菌生物膜对不同消毒因子的抗力研究

目的研究铜绿假单胞菌生物膜对不同消毒因子的抗力。方法采用Brown平板改良法、持续灌流培养技术、载体定量杀菌试验以及扫描电镜技术进行人工培养生物膜对不同消毒因子的抗力研究。结果体外连续培养5~7 d的聚四氟乙烯管内壁的铜绿假单胞菌生物膜形成稳定,不易冲洗脱落,膜中细菌浓度达105~106CFU/cm2,生物膜对0.55%邻苯二甲醛(OPA)耐受时间为3 min,作用5 min可达到完全杀灭;对200 mg/L有效氯耐受时间为5 min,作用7 min可达到完全杀灭;500 mg/L有效碘耐受时间为10 min,作用20 min可达到完全杀灭;对1000 mg/L聚六亚甲基双胍盐酸盐(PHMB)作用30 min仍然有大量细菌存活。结论体外培养生物膜对0.55%邻苯二甲醛2、00 mg/L有效氯5、00 mg/L有效碘、1000 mg/L PHMB均有不同程度的抵抗力,应引起医院消毒的高度重视。     

多种消毒剂对病毒灭活效果的实验研究

目的研究高、中、低效消毒剂对脊髓灰质炎病毒的灭活效果及有机物浓度对其的影响.方法根据含氯类（次氯酸钠、三氯异氰尿酸钠）、过氧化物类、醛类、含碘类（强力碘、碘伏、碘酊、聚酮维碘）、季铵盐类、复方氯己定等多种消毒剂的适当浓度和作用时间对微生物的杀灭能力,进行灭活病毒的实验研究,并比较灭活效果.结果次氯酸钠400 mg/L作用15 min,三氯异氰尿酸钠500 mg/L作用15 min,二氧化氯100 mg/L作用10 min,聚维酮碘4 048 mg/L作用30 min,复方戊二醛806.4 mg/L作用1 h,对脊髓灰质炎病毒的灭活对数值均＞4.00;而强力碘、碘伏、碘酊、复方季铵盐类、复方氯己定等消毒剂对脊髓灰质炎病毒的灭活对数值均＜4.00.有机物浓度由10%上升至20%时,消毒剂作用15 min,灭活对数值下降0.62,作用30 min,灭活对数值下降0.63.结论高效及部分中效消毒剂对脊髓灰质炎病毒有较好的灭活效果,低效消毒剂对脊髓灰质炎病毒无灭活效果.有机物浓度增高可影响消毒剂对病毒的灭活效果.     

肺炎克雷伯菌抗药基因检测与消毒剂抗性相关性分析

目的 研究医院临床分离及环境检出的肺炎克雷伯菌对消毒剂抗性水平和抗药基因携带的关系.方法 采用最低抑菌浓度(MIC)、最小杀菌浓度(MBC)、聚合酶链反应(PCR)等试验方法,分析临床分离及环境中检出的肺炎克雷伯菌qacE△1-sulI基因携带和对消毒剂的抗性.结果 10株肺炎克雷伯菌中有2株临床分离的多药耐药菌qacE△1-sul I基因为阳性,8株环境检出菌株均为阴性;三氯异氰尿酸对10株肺炎克雷伯菌的MIC、MBC值均为500～1000 mg/L,标准菌株为500 mg/L;聚乙烯吡咯烷酮碘对10株肺炎克雷伯菌的MIC值为200～800 mg/L,标准菌株为400 mg/L;戊二醛对10株肺炎克雷伯菌的MIC值为1250～2500 mg/L,标准菌株为1250 mg/L.结论 临床分离的肺炎克雷伯菌qacE△-sul I基因携带率高于环境检出菌株,部分抗药基因阳性菌株对消毒剂产生抗性.     

ICU环境致病菌对常用消毒剂抗性的研究

目的研究ICU环境中分离出的致病菌株对常用消毒剂的敏感性,为科学选择和合理使用消毒剂,提高ICU预防性消毒工作质量提供依据。方法通过最小抑菌浓度试验(MIC),检测环境分离菌株对邻苯二甲醛、含氯消毒剂、碘伏和酒精的敏感性,与标准菌株相比较,判断菌株的消毒剂抗性水平。结果邻苯二甲醛对各试验菌的MIC值除大肠埃希菌与标准菌株一致以外,其他试验菌的MIC值均高于标准菌株;碘伏消毒液对90.0%屎肠球菌的MIC值高于标准菌株;含氯消毒液对革兰氏阴性菌的MIC值显著高于标准菌株;酒精对所有实验菌株的MIC值均与标准菌株一致。结论 ICU环境分离出的菌株已经对临床常用的邻苯二甲醛、含氯消毒液和碘伏消毒液产生不同程度的抗性。     

Mechanisms of inactivation of bacteriophage phiX174 and its DNA in aerosols by ozone and ozonized cyclohexene.

The mechanisms of inactivation of aerosolized bacteriophage phiX174 in atmospheres containing ozone, cyclohexene, or ozonized cyclohexene were studied by using 32P-labelled phage. The inactivation of the aerosolized phage in clear air or in air containing cyclohexene is due to damage of the protein coat since the deoxyribonucleic acid (DNA) extracted from the inactivated phage retains its biological activity. Inactivation of the phage in air containing ozonized cyclohexene is due both to protein and DNA damage. Sucrose gradient analysis shows that aerosolized inactivated phiX174 releases unbroken DNA. In contrast, the DNA from phage phiX174 inactivated by ozonized cyclohexene is broken. The inactivation of aerosolized phage phiX174-DNA was studied in the same atmospheres using 32P-labelled DNA. phiX174-DNA aerosolized in clear air or air containing cyclohexene at 75% r.h. is inactivated by a factor of 2 in 30 min. The inactivated DNA is broken. Ozone as well as ozonized cyclohexene inactivates KNA very fast causing breaks in the molecule. This is in contrast with the intact bacteriophage in which ozone does not produce breaks in the DNA.     

医院感染病原菌对抗菌药物和消毒剂的耐药现状分析

医院感染既是公共卫生问题,也是严重的临床问题;医院感染的发生不仅导致患者发病率和病死率的增加,也增加了医疗费用;医院感染的发生常由对抗菌药物耐药的病原菌所导致,而医院环境物体表面和医务人员的手既可成为病原微生物载体,也可形成一个感染传播的交叉链条,与医院感染的发生密切相关;因此,如何正确选择消毒剂有效地杀灭病原微生物成为有效预防控制医院感染发生的关键环节,最为关注的是,病原菌携带对消毒剂的耐药基因,并对常用消毒剂出现耐药;现就对医院感染病原菌对抗菌药物和消毒剂的耐药现状作一综述。