氯灭活水中脊髓灰质炎病毒机制的研究

目的探讨氯对脊髓灰质炎病毒核酸和衣壳蛋白的破坏在灭活病毒中的作用,并对病毒基因组受损区域进行定位,阐明氯灭活脊髓灰质炎病毒的机制。方法以不同剂量(0.1、0.5、1.0、1.5和2.0mg/L)的有效氯对脊髓灰质炎病毒作用不同时间(0、15、30、45和60min),采用大片断逐步步移PCR(long-overlapping PCR)分析氯对病毒全基因组的损伤,以ELISA技术分析氯对病毒衣壳蛋白的破坏,以细胞培养检测病毒感染性。结果脊髓灰质炎病毒各部分对氯的抵抗力强弱存在如下关系:病毒衣壳>基因组蛋白编码区>基因组5′端非编码区(noncoding region,NCR)>基因组3′端NCR>poly A尾;脊髓灰质炎病毒的polyA尾和3'端NCR破坏可造成病毒的感染性下降,但不能完全灭活病毒;5′端NCR的破坏与病毒感染性的消失一致,损伤区域主要位于富含二级结构的区域。结论氯主要通过破坏脊髓灰质炎病毒核酸而非衣壳蛋白灭活病毒;病毒基因组5′NCR内二级结构区域的破坏对脊髓灰质炎病毒具有致死效应。     

二氧化氯灭活水中肠道腺病毒及其分子机制研究

目的 探讨二氧化氯对肠道腺病毒41型(AdV41)核酸的破坏在灭活病毒中的作用,并对病毒基因组受损区域进行定位,阐明二氧化氯灭活腺病毒的消毒规律和机制.方法 在25℃,pH 7.2条件下,以不同剂量(0.1、0.5、0.7、1.0、2.0 mg/L)的二氧化氯对AdV41作用不同时间(0、0.5、1、2、3、4、5、7、10、20、30、60 min);采用大片段逐步步移PCR(long-overlapping PCR)分析二氧化氯对病毒全基因组的损伤,以细胞培养法检测病毒感染性.结果 二氧化氯浓度变化符合幂函数Ct=a0×e-kt规律;病毒的灭活率随着Ct值的增加而逐渐增高;当Ct=0.773 mg/(L· min)时,二氧化氯对AdV41可以达到4log的灭活对数值(即灭活率为99.99％).AdV41基因组各部分对二氧化氯的抵抗力不同,其5’的1～2 081 nt区域的破坏与AdV41感染性的消失一致.结论 AdV41基因组5’的1～2 081 nt区域对二氧化氯最为敏感,且与病毒的感染性相关;在25℃,pH 7.2时二氧化氯灭活4log AdV41的G值为0.773 mg/(L·min).     

液氯和二氧化氯对病毒灭活作用对比实验研究

应用病毒细胞病变法（ＣＰＥ）研究液氯和二氧化氯对六种病毒［脊髓灰质炎病毒Ⅰ型（ｐｏｌｉｏ＿１）、柯萨奇病毒Ｂ＿３（ＣＶＢ＿３）、艾可病毒１１型，（ＥＣＨＯ＿１１）、腺病毒７型（ＡｄＶ＿７）、单纯性疱疹病毒Ⅰ型（ＨＳＶ＿１）、腮腺炎病毒（ＭＶ）］的灭活作用。结果表明，液氯投置最高浓度达７．０ｍｇ／Ｌ、作用时间６０分钟时对上述六种病毒均达不到灭活效果。而二氧化氯投置仅在１．０ｍｇ／Ｌ、作用时间３０分钟时即可达到灭活效果。二氧化氯在ｐＨ３．０～７．０时对病毒有显著的灭活作用。总之，二氧化氯是一种优于液氯的广谱、高效、快速的饮水杀病毒剂。     

脊髓灰质炎病毒实时荧光定量RT-PCR检测方法的 建立及应用

摘要:目的　在省级脊髓灰质炎（脊灰）实验室建立一种快速、灵敏、准确的脊灰病毒（Poliovirus,PV）型内鉴定（Intratypic Differentiation,ITD）及基因型鉴定的方法。方法　以PV衣壳蛋白（Capsid Protein）VP1编码区基因序列为目标,设计并合成引物和 Taqman 探针,建立实时荧光定量RT-PCR（Real-time RT-PCR,rRT-PCR）检测体系,并考察该方法的重复性、灵敏性和特异性。结果　该方法能快速、灵敏地鉴定出PV血清型及毒株类型,在1.0×108 copies/μl～1.0×103 copies/μl检测范围之间有良好的线性关系,相关系数为0.993,最低检测限为103.5CCID50/0.1 ml。结论　成功在省级实验室建立了PV的r RT-PCR检测技术,该技术特异性强,敏感性高,操作简便快速,适用于PV的型内鉴定和基因型鉴定,可应用于实验室诊断,为免疫策略快速提供依据。     

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.     

生菜共生菌对诺如病毒灭活的影响

目的了解生菜共生菌对诺如病毒灭活的影响及机理。方法从农田和超市采集生菜样品,分离鉴定共生菌;加共生菌的诺如病毒液为实验组,不加共生菌为对照组。采用高温、紫外线、含氯消毒剂灭活,分析实验组与对照组病毒量比值,评价共生菌对诺如病毒抗灭活能力的影响;通过检测共生菌对紫外线破坏病毒衣壳蛋白的影响和对病毒吸附能力的影响研究共生菌作用机理。结果共鉴定11株生菜共生菌,均为杆菌,以假单胞菌属为主。10株生菜共生菌能提高诺如病毒抗高温灭活能力,其中稻田叶螨微杆菌、台湾贪铜菌(SC061204)、古川假单胞菌、烟粉虱肠杆菌和食树脂假单胞菌(SC061211)较为显著;11株菌均能提高诺如病毒抗紫外线灭活能力,其中恶臭假单胞菌、稻田叶螨微杆菌和烟粉虱肠杆菌较为显著;恶臭假单胞菌能提高诺如病毒抗二氧化氯灭活能力,危害等级为Ⅰ级。恶臭假单胞菌、稻田叶螨微杆菌、烟粉虱肠杆菌能显著降低紫外线对诺如病毒衣壳蛋白的破坏作用。9株共生菌促进诺如病毒吸附,吸附促进率为1.04%～46.73%;恶臭假单胞菌和食树脂假单胞菌(SC061211)抑制诺如病毒吸附,吸附促进率分别为-6.50%和-19.85%。结论生菜共生菌可能通过保护诺如病毒衣壳蛋白和促进病毒吸附来提高诺如病毒抗灭活能力,在灭活诺如病毒的过程中应控制共生菌的存在。     

用聚合酶链反应技术研究含氯消毒剂对乙型肝炎病毒的杀灭作用

本文研究了聚合酶链反应测定乙型肝炎病毒灭活效果的方法，并用该方法研究了氯消毒剂对乙型肝炎病毒的灭活作用，结果表明，灭活１０倍聚合酶链反应灵敏度的Ｄａｎｅ颗粒中核酸，需要有效氯２５００ｍｇ／Ｌ作用３０分钟以上，研究有机物对灭活作用的影响表明，１％小牛血清可使氯破坏作用减弱。由此推测，Ｄａｎｅ颗粒中核酸对含氯消毒剂有较高的抵抗力，并讨论了含氯消毒剂对乙型肝炎病毒的灭活机理。     

二氧化氯灭活水中病毒

二氧化氯作为一种替代氯的消毒剂，其灭活病毒的作用强于或与氯相仿。其受ｐＨ影响与氯不同，一般认为在ｐＨ值高时其灭活效果更好；不受氨的影响，亚硝酸盐对其消耗较大，不同的病毒种属对其耐性也不同，与氯联合使用可能存在协同消毒作用。二氧化氯灭活病毒的机理，有报道认为作用于核酸，也有报道作用于病毒外壳蛋白，还有其它的一些报道，但都没有最后确定。     

微电流协同低浓度氯对脊髓灰质炎Ⅰ型病毒的灭活作用

目的观察微电流与游离氯对水中脊髓灰质炎Ⅰ型病毒(PV1)的协同灭活效果.方法用微电流0.4～.2mA·cm^-2协同氯0.2mg·L^-1处理污染PV1水样,比较作用前后灭活率K值评价灭活效果,用透射电镜观察病毒形态变化.结果电流密度达到1.2mA·cm^-2与0.2mg·L^-1氯对水中PV1有协同灭活效应,与单独氯相比有显着差别,增加了氯的灭活效果,微电流作用后透射电镜下病毒颗粒集聚程度降低.结论微电流协同氯可提高低浓度氯灭活水中病毒的效果.     

Inactivation of human rotavirus, SA11 and other enteric viruses in effluent by disinfectants.

A preparation of infectious human rotavirus, isolated from faeces and resuspended in wastewater effluent, was shown to be inactivated by chlorine, chlorine dioxide, ozone and peracetic acid. Infectivity was assayed in MA 104 cells by the detection of cell-associated viral antigen by immunofluorescence. The inactivation curves were similar to those reported for other enteric viruses. Human rotavirus was at least as resistant as poliovirus, coxsackievirus, echovirus and f2 coliphage and was strikingly less sensitive to inactivation than the simian rotavirus, SA11. The latter was generally the most sensitive of the six tested viruses yet is often taken as being representative of the human rotaviruses.     

Inactivation of human rotavirus, SA11 and other enteric viruses in effluent by disinfectants

A preparation of infectious human rotavirus, isolated from faeces and resuspended in wastewater effluent, was shown to be inactivated by chlorine, chlorine dioxide, ozone and peracetic acid. Infectivity was assayed in MA 104 cells by the detection of cell-associated viral antigen by immunofluorescence. The inactivation curves were similar to those reported for other enteric viruses. Human rotavirus was at least as resistant as poliovirus, coxsackievirus, echovirus and f2 coliphage and was strikingly less sensitive to inactivation than the simian rotavirus, SA11. The latter was generally the most sensitive of the six tested viruses yet is often taken as being representative of the human rotaviruses.     

Virucidal effect of chlorinated water containing cyanuric acid

The inhibitory influence of cyanuric acid on the virucidal effect of chlorine was studied. The time required for 99.9% inactivation of ten enteroviruses and two adenoviruses by 0.5 mg/l free available chlorine at pH 7.0 and 25 degrees C was prolonged approximately 4.8-28.8 times by the addition of 30 mg/l cyanuric acid. Comparative inactivation of poliovirus 1 by free available chlorine with or without cyanuric acid revealed the following. The inactivation rate by 1.5 mg/l free available chlorine with 30 mg/l cyanuric acid or by 0.5 mg/l free available chlorine with 1 mg/l cyanuric acid was slower than by 0.5 mg/l free available chlorine alone. Temperature and pH did not affect the inhibitory influence of cyanuric acid on the disinfectant action of chlorine. In the swimming-pool and tap water, cyanuric acid delayed the virucidal effect of chlorine as much as in the 'clean' condition of chlorine-buffered distilled water. The available chlorine value should be increased to 1.5 mg/l when cyanuric acid is used in swimming-pool water.     

A comparison of the virucidal properties of chlorine, chlorine dioxide, bromine chloride and iodine.

Chlorine dioxide, bromine chloride and iodine were compared with chlorine as virucidal agents. Under optimal conditions all disinfectants were effective at low concentrations, but each disinfectant responded differently to acidity and alkalinity. Disinfection by chlorine was impaired by the presence of ammonia, but the other disinfectants retained much of their potency. Disinfection of poliovirus by iodine resulted in structural changes in the virions as seen by electron micrroscopy, but the other disinfectants were able to inactivate poliovirus without causing any apparent structural changes.     

A comparison of the virucidal properties of chlorine, chlorine dioxide, bromine chloride and iodine

Chlorine dioxide, bromine chloride and iodine were compared with chlorine as virucidal agents. Under optimal conditions all disinfectants were effective at low concentrations, but each disinfectant responded differently to acidity and alkalinity. Disinfection by chlorine was impaired by the presence of ammonia, but the other disinfectants retained much of their potency. Disinfection of poliovirus by iodine resulted in structural changes in the virions as seen by electron micrroscopy, but the other disinfectants were able to inactivate poliovirus without causing any apparent structural changes.     

Inactivation of Bacteriophage MS‐2 and poliovirus in copper,galvanized and plastic domestic water pipes

Survival of bacteriophage MS‐2 and poliovirus was evaluated in new and aged copper, galvanized and plastic polymer (polybutylene, cross‐linked polyethylene, polyvinylchloride) pipes. Inactivation rates (k = — [log₁₀C_t — log₁₀C₀]/t) were calculated as a log₁₀ reduction h^‐1. Levels of copper leached from copper pipes, over a period of 24 h, ranged from 400–800 μg 1^‐1. Numbers of viable MS‐2 were reduced significantly in copper pipes (k = 0.32) compared to plastic polymer pipes (k: = 0.03). New galvanized pipes showed greater inactivation of MS‐2 (k = 2.57) when compared to new copper pipes, and similar rates were also observed in the aged pipes. Poliovirus showed more resistance (k = 0.015 and 0.009 for copper and galvanized pipes, respectively) to the action of copper and galvanized pipes than MS‐2. Addition of 0.20 (μg 1^‐1 free chlorine to water containing 400 (μg 1^‐1 leached copper significantly enhanced the inactivation of both viruses (k = 4.74 for MS‐2 and 0.04 for poliovirus, respectively) when compared to either copper or chlorine alone. Less copper was released from aged copper pipes compared to the new ones, resulting in a significantly lower inactivation of MS‐2 (new, k = 0.32; aged, k = 0.13). The use of copper or galvanized pipes in water distribution systems may serve as an additional protection against viral contamination.     

Inactivation of viruses in municipal effluent by chlorine

The influence of pH and temperature on the efficiency of chlorine inactivation of two unrelated picornaviruses in a typical urban wastewater effluent was examined. Temperature, unlike pH, had relatively little effect on the rate of inactivation. The pH effect was complex and the two viruses differed. The f2 coliphage was more sensitive to chlorine at low pH, but at all values there was a threshold above which additional chlorine resulted in very rapid inactivation. The amount of chlorine required for this was less at low than at high pH, although at pH values above 7 the extent of inactivation was about the same. There was no apparent correlation between pH and rate of inactivation of poliovirus but there was a suggestion that at a pH close to the isoelectric point of the virus it was less sensitive to chlorination.