常用消毒剂对布鲁氏菌疫苗株的灭菌效果评估

【背景】布鲁氏菌是一种重要的人畜共患胞内寄生菌,是引起动物和人发生布鲁氏菌病(布病)的病原体。高效消毒剂杀灭环境中的布鲁氏菌是防控布病的关键措施。【目的】评价市面上常用消毒剂对布鲁氏菌的灭菌效果及差异。【方法】选用市面上9种不同类型的常用消毒剂,以高、中、低3种不同使用浓度分别研究其对牛种、羊种和猪种布鲁氏菌的杀灭效果。同时根据消毒剂的有效浓度通过最小抑菌浓度实验确定各消毒剂的最小抑菌浓度。【结果】除苯酚外,其余8种消毒剂,包括聚维酮碘、癸甲溴铵、苯扎溴铵、戊二醛、复合季铵盐、乙醇和2种商品化消毒剂等在推荐使用浓度下5 min内均能完全杀灭布鲁氏菌,碘酸制剂在0.1%低使用浓度下细菌存活率为0.000039%-0.000095%。苯酚按0.5%的推荐剂量,作用5 min后细菌存活率为0.000144%-0.000183%,20 min后,细菌存活率为0.000138%-0.000193%;按1%的使用剂量作用5 min后,猪种布鲁氏菌存活率为0.000125%,作用20min后的存活率下降至0.000038%。最小抑菌浓度研究结果表明,季铵盐类消毒剂其最小抑菌浓度大致在0.01563%-0.03125%之间,其余消毒剂的最小抑菌浓度结果与消毒剂最低推荐使用浓度基本一致。研究同时发现,不同种属布鲁氏菌对同一消毒剂的敏感性也存在一定差异。【结论】研究结果为生产实践中科学选择布鲁氏菌消毒剂提供了借鉴。     

戊二醛复合消毒剂对猪病病毒杀灭效果的研究

目的　研究戊二醛复合消毒剂对猪病病毒的杀灭效果。方法　将猪细小病毒 (porcinepavrovirusvirus ,PPV)、猪繁殖呼吸综合征病毒 (porcinereproductiveandrespiratorysyndromevirus,PRRSV)和猪伪狂犬病病毒(porcinepseudorabiesvirus,PRV)分别与不同浓度的戊二醛复合消毒剂作用后 ,接种于长满细胞单层的细胞培养板中 ,根据细胞是否产生病变情况 ,确定消毒剂杀灭病毒的最佳浓度 ;同时 ,还将不同浓度的消毒剂与猪瘟病毒 (hogchloeravirus,HCV)作用后 ,对兔进行静脉注射 ,根据兔的体温变化情况 ,判断消毒剂杀灭病毒的最佳浓度。结果　1%浓度的消毒剂 ,可在 2 0min之内有效杀灭PPV、PRRSV和PRV ;0 5 %浓度的消毒剂 ,可在 10min之内有效杀灭HCV。结论　戊二醛复合消毒剂具有高效杀灭病毒的作用 ,适用于养殖场、医疗卫生行业及传染病流行地区的消毒灭菌 ;采用细胞感染法检测和评价消毒剂对病毒的杀灭效果是一种可行的体外试验方法     

一株甲醛降解菌的筛选及降解特性的研究

【目的】以甲醛为唯一碳源与能源,以期从印染厂采集的活性污泥中筛选出快速降解甲醛的菌株。【方法】采用传统微生物纯培养方法和形态学特征、生理生化试验,结合16S rRNA基因序列分析以及甲醛关键脱氢酶(FDH)对筛选的菌株W1进行系统研究,并利用正交设计法研究不同因素处理对菌株W1降解甲醛特性的影响。【结果】分类结果显示鉴定菌株W1属于恶臭假单胞菌(Pseudomonas putida),通过单因素试验和正交试验考察培养条件对菌株降解甲醛的影响,得出菌株W1降解甲醛的最适条件为:甲醛浓度为500 mg/L,温度30°C,pH 6.0,摇床转速为200 r/min,接种量为3%。【结论】在最适条件下菌株W1具有较强的降解甲醛能力,在24 h其甲醛降解率达98%。     

一株兔出血症病毒2型毒株的分离鉴定

【背景】我国于2020年4月突发兔出血症病毒2型(Rabbit Hemorrhagic Disease Virus 2,RHDV2)疫情,严重威胁兔养殖业和生态平衡,而且目前国内对RHDV2的病原学以及遗传特征等基础研究匮乏。【目的】分离鉴定RHDV2毒株,对分离株进行全基因测序与遗传进化分析。【方法】对成都某兔场疑似RHDV2感染致死的家兔进行病理剖检,通过RT-qPCR检测和动物回归试验,分离鉴定得到RHDV2毒株,进一步进行全基因测序及遗传进化分析。【结果】病死兔剖检表现为各实质器官出血肿大,以心、肺、肝脏尤为明显,经RT-qPCR确诊为RHDV2,而且不存在其他病原混合感染,试验感染家兔可致相似病变。将分离株命名为SCCN03,其基因序列全长为7464bp,与参考毒株(GenBank登录号为MN901451.1)一致性为99.21%。对比参考株氨基酸序列,分离株的非结构蛋白和结构蛋白氨基酸序列发生了多处错义突变,其中非结构蛋白p16和结构蛋白的几处错义突变可能与毒株变异有关。进化树显示毒株SCCN03属于GI.2基因型。【结论】分离鉴定出一株RHDV2毒株,获得其基因序列,丰富了RHDV2的全基因数据资料,为后续RHDV毒力相关研究和相关疫苗研发奠定了基础。     

乳杆菌生态消毒剂杀菌效果的试验观察

目的:在实验室对以乳杆菌发酵液为主要成分的乳杆菌生态消毒剂进行杀灭微生物效果观察.方法:采用定量杀菌法试验、稳定性试验、皮肤刺激性试验和阴道黏膜刺激性试验方法进行.结果:以该剂原液对大肠埃希菌、金黄色葡萄球菌、白色念珠菌作用10 min,杀灭率均达91.67%以上;对德氏乳杆菌和干酪乳杆菌作用10 min,杀灭率分别是25.15%和55.77%.本消毒剂于54℃条件下放置14 d,杀菌效果无明显变化,对皮肤无刺激性,对阴道为轻度刺激性.结论:伊清爽乳杆菌阴道生态消毒剂具有杀灭和抑制有害菌,扶植乳酸菌的作用,是新一代保健型阴道卫生用品.     

等离子体射流灭活液体中铜绿假单胞菌的研究

【目的】测定等离子射流对铜绿假单胞菌(Pseudomonas aeruginosa)的灭活效果,探究低温等离子体射流的杀菌机理。【方法】采用平板计数法测定等离子体射流的杀菌效果,荧光显微镜、透射电镜观察等离子体作用后菌体结构的变化,蛋白浓度测定和SDS-PAGE电泳检测菌液上清液中可溶性蛋白的泄漏量。【结果】等离子体射流处理铜绿假单胞菌菌液5 min,杀灭率可达到99.9%以上。透射电镜观察可见细菌菌体结构发生改变,细胞壁、细胞膜损伤破裂,细胞内容物泄露。进一步对处理铜绿假单胞菌上清液中的蛋白质含量变化进行检测,结果显示随着处理时间的增加,上清液中蛋白质含量持续增加,在2 min时达到最大值。【结论】等离子体射流可以通过破坏细胞结构造成细胞质泄露,使其丧失正常的细胞功能,从而达到快速有效地杀灭铜绿假单胞菌的效果。     

甲型肝炎病毒对理化因子的稳定性

用放射免疫成斑法研究了甲型肝炎病毒FM-175株的理化稳定性和灭活条件,证明甲型肝炎病毒理化稳定性与其它肠道病毒相似,具有广范围的pH(2～10)稳定性;Mg~(++)和Ca可增强其热稳定性,不能抵抗冷冻干燥,但对热的抵抗力明显高于普通肠道病毒,可被紫外线迅速杀灭,也可被多种消毒剂如3～8％的甲醛液,50～90％的乙醇,2％的石炭酸及400ppm的有效氯等杀灭,但可抵抗0.1％甲醛液,2～5％的来苏儿及200ppm的有效氯1小时以上,本研究工作为甲型肝炎病毒的理化性状、保存及消毒条件等提供了实验数据。     

二氧化氯溶液消毒剂对呼吸道病毒的杀灭效果评估

目的:评估"菌bye-bye"消毒剂对甲型H1N1流感病毒PR8(PR8)、呼吸道合胞病毒(RSV)、3型腺病毒(ADV3)、人感染H7N9禽流感病毒(H7N9)的体外杀灭效果。方法:参考《消毒技术规范》和受试产品说明书进行细胞毒性试验、消毒剂中和试验和对PR8、RSV、ADV3、H7N9病毒的体外杀灭实验。结果:(1)候选中和剂选定0.02mol/L硫代硫酸钠(Na_2S_2O_4);(2)候选中和剂、"菌-bye-bye"消毒剂及两者混合物对细胞毒性低;(3)候选中和剂能完全中和消毒剂消毒效果;(4)随着"菌bye-bye"消毒剂的浓度增大,病毒杀灭效果亦越好。在其不稀释的条件下,除了PR8毒株外,其他3种病毒的平均灭活率均在99.99%以上,且平均病毒TCID50负对数值(log_(10)TCID_(50)/m L)均降低4 log_(10)或以上;对半稀释后对RSV的杀灭效果最好,而对ADV3的杀灭效果最差。结论:高浓度"菌bye-bye"消毒剂对呼吸道病毒的杀灭效果较好,且对细胞的毒性较小,是一种安全、高效的消毒剂,值得临床推广。     

四溴甘脲对枯草杆菌黑色变种芽胞损伤作用的电镜观察

为探索四溴甘脲消毒剂杀灭细菌的机理,采用透射电镜技术对四溴甘脲消毒剂处理过的枯草杆菌黑色变种芽胞的超微结构进行了分析和比较.结果显示,以含有效溴274mg/L的四溴甘脲消毒剂作用30min,可使枯草杆菌黑色变种芽胞杀灭率达到100%.在透射电镜下观察到,经该消毒剂作用的枯草杆菌黑色变种芽胞壳质破损断裂明显,壳内结构模糊,核心溶解,有的芽胞近似空壳.结果显示,四溴甘脲消毒剂杀灭芽胞效果优于普通含氯消毒剂,对细菌芽胞超微结构破坏明显.     

一株好氧反硝化菌的分离鉴定及其除氮特性

【目的】生物除氮中反硝化菌具有重要的作用,需氧反硝化菌研究较少,有着很好的应用潜力,本研究主要从环境样品中分离具有高效去除铵氮和亚硝酸盐氮活性的好氧反硝化菌,并对其分类及除氮特性进行研究。【方法】以高效去除铵氮、除亚硝酸盐氮和好氧反硝化能力为主要指标,从富营养化的池塘淤泥水和工厂污泥样品中进行菌株分离筛选。通过生理生化特点以及16S rRNA序列分析对活性最好的菌株进行初步鉴定。在好氧条件下,分别以NO-3-N、NH+4-N和NO-2-N作为唯一氮源,考察菌株的好氧反硝化特性、去除铵氮和亚硝酸盐氮特性,以及不同初始pH值、温度、碳源、摇床转速对该菌去除铵氮和亚硝酸盐氮特性的影响。【结果】得到的细菌中,以菌株C-4的活性最好,其16S rRNA序列与不动杆菌的同源性达99%,结合生理生化特点,初步确定菌株C-4属于不动杆菌属(Acinetobacter sp.)。以柠檬酸钠作为碳源,30℃、120 r/min振荡培养,种龄为18 h,用初始pH为8.5的200 mg/L NH +4-N培养基和初始pH为7.5的100 mg/L NO -2-N培养基进行测定,分别培养15 h与12 h,净除氮率分别达到65.8%和47.8%。【结论】从鱼塘水样中分离到一株好氧反硝化菌C-4,初步鉴定为不动杆菌属的一个种(Acinetobacter sp.),具有较高的反硝化特性和高效去除铵氮与亚硝酸盐氮的能力,在处理实际池塘污水时中,净除氮率可达73.04%以上。     

多药耐药大肠杆菌对不同消毒剂的抗性探究

目的：研究多药耐药大肠杆菌对不同消毒剂的抗力水平,为临床上合理选择消毒剂提供依据。方法：采用营养肉汤稀释法及悬液定量杀菌实验分别测定临床分离出的具有多重耐药性的大肠杆菌对临床常用消毒剂的最低抑茵浓度（minimum inhibitory concentration,MIC）及不同作用时间消毒剂对菌株的杀灭率,并与大肠杆菌标准株的测定结果进行比较。结果：不同消毒剂对多药耐药大肠杆菌的MIC值不同,洁芙柔消毒凝胶的MIC值为2．8±1．9,绿莎新爱尔施牌消毒片的MIC值为2583．4±1107．2,爱护佳免洗手消毒液的MIC值为144．63：86．9,安尔碘II型皮肤消毒剂的MIC值为16．1±7．7。4种常用消毒剂对多要耐药大肠杆菌的MIC值均高于标准菌,绿莎新爱尔施牌消毒片及爱护佳免洗手消毒液的MIC值与标准大肠杆菌较为接近。另外,4种常用消毒剂在常用浓度下对标准大肠杆菌和多药耐药大肠杆菌作用5min的杀灭率均能打到100％,标准大肠杆菌的被杀灭率略高于多药耐药大肠杆菌。结论：多药耐药菌株对消毒剂的抗性日益受到关注,使用时调整浓度、加强消毒剂科学管理对控制医院感染具有重要意义。     

Efficacy of some commerical disinfectants against the bacterial isolates from a poultry slaughterhouse in Turkey

In this study, efficacy of seven different commercial disinfectant preparations was investigated against characteristic bacteria of a poultry slaughterhouse in Ankara (Turkey) by using paper disc-agar diffusion method and surface effectiveness test. According to paper disc-agar diffusion method, some disinfectants had wide efficacy against the test bacteria. The disinfectant effectiveness generally increased by the increasing of disinfectant concentration. However, some disinfectants were ineffective even though at their highest concentrations. The most effective disinfectant was B which contains QAC as active agent.Staphylococcus spp.,Staphyloccus aureus andEscherichia coli were the most sensitive bacteria to the disinfectants. Some pathogenic isolates, especiallySalmonella spp. andCampylobacter spp., were the most resistant ones to many of the disinfectants tested. The results of paper disc-agar diffusion method indicated the importance of characteristic bacterial strains of food plants as the test bacteria for disinfectant efficacy tests. Conversely of paper disc-agar diffusion method, all disinfectants were effective against the isolates by surface effectiveness test depending on exposure time. The disinfectants, except A and F, produced at least 3 log unit reduction during 5 min of exposure. However, all disinfectants at their lowest concentrations were effective against all tested bacteria during 15 and 30 min by this test.     

Chemical Disinfection of Holding-Tank Sewage

A number of chemical disinfectants were evaluated for their bactericidal and virucidal effectiveness in holding-tank sewage. It was found that the disinfection efficiencies of formaldehyde, benzalkonium chloride, cetylpyridinium chloride, and methylene blue were markedly improved if the pH of the sewage was raised from 8.0 to 10.5. When formaldehyde, benzalkonium chloride, and methylene blue were tested with either 2-week holding times with no sewage additions or 10-day holding times with daily sewage additions, disinfection effectiveness was maintained as long as the sewage pH was kept at 10.5 and the disinfectant concentration was kept at 100 mg/liter or more. Calcium hypochlorite, zinc sulfate, and phenol were found to be relatively ineffective disinfectants for holding-tank sewage.     

Additional disinfectants effective against the amphibian chytrid fungus Batrachochytrium dendrobatidis

Chytridiomycosis, a disease contributing to amphibian declines worldwide, is caused by the fungus Batrachochytrium dendrobatidis. Identifying efficient and practical disinfectants effective against B. dendrobatidis is important to reduce the spread of the disease both in the wild and captivity. Previous studies identified a range of suitable disinfectant strategies. We evaluated the suitability of 3 additional disinfectants: two of these (TriGene Virucidal Disinfectant Cleaner and F10 Super Concentrate Disinfectant) are mixtures of chemicals and one (Betadine Antiseptic Liquid) contains a single active ingredient, povidone iodine. The disinfectants were tested using a range of concentrations for 1,5 and 10 min to determine their ability to kill B. dendrobatidis in vitro. The measure of effectiveness was 100% kill of zoosporangia grown in multiwell plates. All disinfectants had a 100% efficacy at concentrations recommended by the manufacturers. The lowest concentrations capable of 100% kill after exposure for 1 min were 0.1 ml l(-1) for TriGene, 0.33 ml l(-1) for F10 and 100 ml l(-1) for Betadine. TriGene is the most effective disinfectant yet to be found, and both TriGene and F10 are more effective than various disinfectants tested in previous studies. TriGene and F10 are considered suitable for use in the field, as only small amounts of concentrate are needed.     

Stability of Minute Virus of Mice to Chemical and Physical Agents

Minute virus of mice (MVM), a single-stranded deoxyribonucleic acid Parvovirus, was subjected to various inactivation procedures, including chemical disinfectants, heat, and ultraviolet radiation. MVM was found to be less stable than has been reported for other Parvoviruses. This virus was readily inactivated by a variety of chemical disinfectants, including alcohols, formaldehyde, glutaraldehyde, and chloroform. MVM was more sensitive to ultraviolet radiation than was Kilham's rat virus. MVM was more sensitive to heating at temperatures of 35 to 100 C than has been reported for other Parvoviruses. More than 95% of MVM infectivity was inactivated by heating (45, 60, or 100 C) for 60 min, acid (pH 2.0) treatment, or ultraviolet radiation treatment, although a small percentage (less than 2%) of the virus preparation was found to be resistant to these treatments. In addition, more than 99% of the infectivity of MVM was lost after storage at 4C for 10 weeks, although the virus was stable on storage in liquid nitrogen.     

细菌抵抗消毒剂及其对抗生素共耐药

消毒剂是一种可杀灭物体表面、器材设备、皮肤、空气和水源等传播媒介上携带的病原微生物的有机分子。它在体外能杀灭病原微生物,切断其传播途径,进而达到控制污染的目的,在生命安全防控中起着重要的作用。但是不合理地使用消毒剂导致细菌对消毒剂产生耐药。消毒剂耐药基因在不同种属间的水平转移加剧其传播风险,使消毒剂耐药情况进一步恶化。更令人担忧的是,细菌对消毒剂的耐药可能会导致对抗生素产生共耐药,给公共安全带来巨大的威胁。但目前为止,对消毒剂耐药以及共耐药的认识还不够全面。本文总结了关于细菌对消毒剂耐药的研究报道,对消毒剂的作用机制、细菌对消毒剂的耐药机制进行了论述,另外针对消毒剂耐药基因的传播以及细菌对消毒剂和抗生素的共耐药进行了综述,为减少消毒剂耐药性的产生和制定合理的消毒剂使用规范奠定基础。     

Surface-Dried Viruses Can Resist Glucoprotamin-Based Disinfection

Touching of contaminated objects and surfaces is a well-known method of virus transmission. Once they are attached to the hands, viruses can easily get adsorbed and initiate infection. Hence, disinfection of frequently touched surfaces is of major importance to prevent virus spreading. Here we studied the antiviral activity of a glucoprotamin-containing disinfectant against influenza A virus and the model virus vaccinia virus (VACV) dried on inanimate surfaces. The efficacy of the surface disinfectant on stainless steel, polyvinyl chloride, and glass coupons was investigated in a quantitative carrier test. Vacuum-dried viruses were exposed to 0.25%, 0.5%, and 1% disinfectant for 5 min, 15 min, and 30 min without agitation, and residual infectivity was determined by endpoint titration. Although glucoprotamin was highly active against both viruses in suspension, limited antiviral activity against the surface-dried viruses was detected. Even after 30 min of exposure to 1% disinfectant, VACV was not completely inactivated. Furthermore, influenza A virus inactivation was strongly affected by the surface composition during the 5-min and 15-min treatments with 0.25% and 0.5% disinfectant. The results presented in this study highlight the relevance of practical tests to assess the antiviral activity of surface disinfectants. High virucidal activity in solution is not necessarily indicative of high antiviral activity against surface-dried viruses. In addition, we want to emphasize that the mere exposure of surfaces to disinfectants might not be sufficient for virus inactivation and mechanical action should be applied to bring attached viruses into contact with virucidal compounds.     

Fungicidal effects of chemical disinfectants, UV light, desiccation and heat on the amphibian chytrid Batrachochytrium dendrobatidis

The efficacy of a number of disinfection treatments was tested on in vitro cultures of the fungus Batrachochytrium dendrobatidis, the causative agent of chytridiomycosis in amphibians. The aim was to evaluate the fungicidal effects of chemical disinfectants, sterilising ultraviolet (UV) light, heat and desiccation, using methods that were feasible for either disinfection in the field, in amphibian husbandry or in the laboratory. The chemical disinfectants tested were: sodium chloride, household bleach (active ingredient: sodium hypochlorite), potassium permanganate, formaldehyde solution, Path-X agricultural disinfectant (active ingredient: didecyl dimethyl ammonium chloride, DDAC), quaternary ammonium compound 128 (DDAC), Dithane, Virkon, ethanol and benzalkonium chloride. In 2 series of experiments using separate isolates of B. dendrobatidis, the fungicidal effect was evaluated for various time periods and at a range of chemical concentrations. The end point measured was death of 100% of zoospores and zoosporangia. Nearly all chemical disinfectants resulted in 100%, mortality for at least one of the concentrations tested. However, concentration and time of exposure was critical for most chemicals. Exposure to 70% ethanol, 1 mg Virkon ml(-1) or 1 mg benzalkonium chloride ml(-1) resulted in death of all zoosporangia after 20 s. The most effective products for field use were Path-X and the quaternary ammonium compound 128, which can be used at dilutions containing low levels (e.g. 0.012 or 0.008%, respectively) of the active compound didecyl dimethyl ammonium chloride. Bleach, containing the active ingredient sodium hypochlorite, was effective at concentrations of 1% sodium hypochlorite and above. Cultures did not survive complete drying, which occurred after <3 h at room temperature. B. dendrobatidis was sensitive to heating, and within 4 h at 37 degrees C, 30 min at 47 degrees C and 5 min at 60 degrees C, 100% mortality occurred. UV light (at 1000 mW m(-2) with a wavelength of 254 nm) was ineffective at killing B. dendrobatidis in culture.