口服轮状病毒活疫苗稳定性观察

目的：了解口服轮状病毒活疫苗的稳定性。方法：将检定合格的6批口服轮状病毒活疫苗2～8℃放置6、9、12、15及37℃放置7、14、21、28d，对其稳定性进行系列试验。结果：疫苗在2～8℃放置时外观及滴度具有良好的稳定性，疫苗滴度改变差异无统计学意义（F=1．001，P〉O．05），37℃加速稳定性实验结果较差，滴度均达不到规程要求。结论：该疫苗运输及使用过程中应注意冷链要求。     

口服液体型脊髓灰质炎减毒活疫苗的稳定性研究

为了评价保存在不同条件下的口服液体型脊髓灰质炎 (脊灰 )减毒活疫苗感染性滴度的稳定性 ,将疫苗分别置 - 2 0℃ 36个月、2～ 8℃ 2 4个月、18～ 2 2℃ 1～ 6周、37℃ 1～ 5d ,用微量滴定法测定疫苗的感染性滴度 ,Reed Muench法计算CCID50 。结果显示 :保存于 - 2 0℃ 30个月、2～ 8℃ 18个月、18～ 2 2℃ 2周、37℃ 3d ,疫苗的感染性滴度平均下降了 0 2 9、0 2 1、0 33、0 38LgCCID50 。表明被检测的口服液体型脊灰减毒活疫苗稳定性较好 ,不同条件下疫苗的感染性滴度下降的程度均在《中国生物制品规程》( 2 0 0 0版 )允许的范围内     

乙脑减毒活疫苗溶解稀释后稳定性观察

目的观察乙脑减毒活疫苗（SA14-14-2）（5人份/瓶）溶解稀释后病毒的稳定性。方法将该乙脑减毒活疫苗加入稀释液PBS（2.5ml/瓶）,溶解稀释后分别置于2℃～8℃、20℃～25℃、37℃存放,在设置的不同时间点,分别测定病毒滴度,观察其病毒滴度变化趋势。结果该乙脑减毒活疫苗溶解稀释后在2℃～8℃、20℃～25℃存放至24h,在37℃存放至14h,病毒滴度下降,但符合《中国药典》2005年版的要求（≥5.7LgPFU/ml）;在37℃存放大于14h后,病毒滴度下降明显,不符合《中国药典》2005年版的要求（≥5.7LgPFU/ml）。结论乙脑减毒活疫苗溶解稀释后在2℃～8℃、20℃～25℃可存放24h,在37℃可存放14h,其病毒滴度符合《中国药典》2005年版的要求（≥5.7LgPFU/ml）。     

重庆市2003～2007年麻疹疫苗和脊灰疫苗效价结果监测分析

[目的]了解麻疹减毒活疫苗(MV)和脊灰疫苗(OPV)的效价在我市冷链系统各环节中的变化,评价我市计免冷链系统及麻疹疫苗和脊灰疫苗管理质量. [方法]于2003～2007年对MV和OPV效价进行常规跟踪监测,在冷链不同环节共检测麻疹疫苗65份,脊灰疫苗64份. [结果]麻疹疫苗效价均值为(3.51±0.53)logTCID50/0.1 ml,脊灰疫苗效价均值为(6.06±0.30)log TCID50/ml,麻疹疫苗质量总合格率达96.92%(合格滴度为t≥2.5log TCID50/0.1ml),脊灰疫苗质量总合格率为96.88%(合格滴度为≥15.7 log TCID50/ml),本中心冷库麻疹疫苗、脊灰疫苗平均滴度与各级监测点相比较,差异无统计学意义(χ2=4.459,P=0.108;χ2=1.898,P=0.387). [结论]我市在麻疹疫苗和脊灰疫苗贮存、运输、接种等各环节冷链系统管理总体良好.     

测定人轮状病毒的一种简易免疫荧光技术

Spendlove(1970年)曾发现蛋白水解酶可以提高呼肠病毒科病毒感染性。随后,Almeida(1978年)证实了在组织培养液中加进胰酶,不仅可以提高牛轮状病毒滴度,而且使病毒能在建立的细胞株和原代细胞中生长。为了提高免疫荧光技术检测人轮状病毒的敏感性,本文研究胰酶在促进人轮状病毒进入组织培养细胞中的作用。     

口服脊髓灰质炎活疫苗糖丸的病毒滴度及其分析

对１９９４～１９９８年共５年间生长的口服脊髓灰质炎活疫苗糖丸的病毒滴度的检定结果进行质量分析。结果显示：近５年生产的口服脊髓同炎活疫苗糖丸中,其病毒滴度稳中有升,平均工由６．１３ｌｏｔＴＣＩＤ５０／人份上升到６．２５ｌｏｇＴＣＩＤ５０／人份;同时疫苗的热稳定性试验结果也在逐步提高,其病毒滴度的平均基础滴度与３７℃４８ｈ平均滴度差值的平均值由０。８７ｌｏｇ／ＴＣＩＤ５０／人份下降到０．６３ｌｏｇ／Ｔ     

肾综合征出血热Vero传代细胞疫苗的研究

目的研究肾综合征出血热(HFRS)Vero传代细胞疫苗。方法将HFRS双价沙鼠肾细胞灭活疫苗的生产疫苗株Z10(Ⅰ型)、Z37(Ⅱ型)适应到Vero细胞上进行连续传代，并用不同代次的Vero细胞适应株制备Vero传代细胞疫苗。结果Z10、Z37，株感染Vero细胞后第1代即可达到较高病毒滴度，并且在Vero细胞中持续传代适应，病毒滴度分别维持在6．25～6．75和6．50～7．00logTCID50／ml之间，较为稳定。用不同代次的Vero细胞适应株制备而成的HFRS Vero细胞灭活疫苗抗原效价和疫苗的病毒滴度有较大提高，反向间接血凝效价从Z10 Cp1 Vero细胞疫苗的阴性上升到Z10 Cp10 Vero细胞疫苗的1：64，从Z37 Cp1 Vero细胞疫苗的1：2上升到Z37 Cp10 Vero细胞疫苗的1：64；疫苗病毒滴度(logTCID50／ml)从Z10 Cp1 Vero细胞疫苗的4．25上升到Z10 Cp10 Vero细胞疫苗的6．50，从Z37 Cp1 Vero细胞疫苗的6．25上升到Z37 Cp10 Vero细胞疫苗的7．50。疫苗在抗原量和病毒滴度上基本符合中国生物制品的要求。结论HFRS Vero传代细胞疫苗的生产，疫苗株在Vero细胞中的连续传代适应起关键性作用。     

麻疹疫苗改变病毒滴度及接种剂量后临床反应观察

从2005年开始，计划免疫用冻干麻疹减毒活疫苗（MV）的病毒滴度增至3．31gCCID50／ml，接种剂量增至0．5ml／剂次^[1]。在此接种剂量下很多接种医生反应儿童接种疫苗后较之前反应明显增多^[2]。为此我院从2006年至2007年两年间进行了MV接种后的临床反应观察，现将结果报道如下。     

冻干甲型肝炎减毒活疫苗稳定性研究

为冻干甲型肝炎（甲肝）减毒活疫苗的生产、贮存、使用等提供科学依据,对甲肝病毒L－A－1疫苗株制备的连续多批冻干甲肝减毒活疫苗,在放置不同温度、不同时间后的稳定性进行了研究。结果表明疫苗置－20℃　28个月、2℃～8℃　20个月、25℃　4个月、37℃　14天,其病毒滴度仍达到≥6.5LogCCID     

甲型肝炎减毒活疫苗的免疫效果与免疫策略

甲型肝炎 (甲肝 )减毒活疫苗 (Ｈ2 株与ＬＡ 1株 )为我国科学家首创。有效率为 6 4 %～ 87% ,抗体阳转率为 30 %～4 0 % [1 4] 。当时所用疫苗滴度偏低 ,仅为 10 5 0～ 5 5ＴＣＩＤ50 。在随后所做的免疫原性试验中 ,我们发现抗体阳转率同疫苗滴度呈剂量效应关系 ,疫苗滴度为 10 6 83 ＴＣＩＤ50 时 ,抗体阳转率为 97 5 % ,滴度为 10 6 17ＴＣＩＤ50 时 ,阳转率为 79 5 % [5] ;因而提出规范化甲肝活疫苗滴度应在 10 6 5ＴＣＩＤ50 以上。一、免疫效果1 预防效果 :(1)预防发病效果 :在河北、广西、上海等地 4 5万余名儿童中进行随机对照试验 …     

甲肝减毒活疫苗与麻疹减毒活疫苗联合免疫的实验研究

目的观察甲肝减毒活疫苗与麻疹减毒活疫苗联合免疫对甲肝疫苗免疫学效果的影响。方法对筛选出的甲肝易感者分两组,分别接种国内A、B两厂家甲肝疫苗,一部分接种者同时在对侧上臂接种了麻疹疫苗,一年时所有观察对象均又加强了一剂甲肝疫苗,于每次疫苗接种后24、48、72h观察局部及全身反应。一年半时检测接种对象血清标本中的抗-HAV。结果甲肝及麻疹疫苗接种后未见明显副反应。B厂家苗联合免疫组抗-HAV几何平均滴度(GMT)高于单纯甲肝疫苗接种组,A厂家苗组未见显著差异。结论甲肝疫苗与麻疹疫苗联合免疫安全性好,接种后不会降低甲肝疫苗免疫学效果。     

三批甲肝减毒活疫苗的人体接种观察

三批甲型肝炎减毒活疫苗（Ｈ２株）接种２．５～１２岁的１１９６０易感儿童结果显示，免疫后未发现有局部和全身性的不良反应，也无肝功酶活性异常升高的现象，接种后四周，抗－ＨＡＶ的阳转率为８２％～９２．５％，说明疫苗安全，有效和免疫原性良好。     

甲型肝炎减毒活疫苗的免疫原性研究

为了对国产规范化的、滴度为 10 6 5TCID50 /ml的甲型肝炎 (甲肝 )减毒活疫苗 (H2 株 )的免疫原性进行研究 ,随机整群选取 3个不同地区的 1790名 3～ 7岁儿童 ,经检测抗甲肝病毒抗体 (抗 HAV)和乙型肝炎 (乙肝 )病毒表面抗原 (HBsAg)均为阴性的 4 13名儿童作为研究对象 ,按出生年月随机分为实验组 (单月 ) 2 0 7名和对照组 (双月 )2 0 6名 ,分别接种甲肝减毒活疫苗和乙肝疫苗 ,并对 2 0 7名实验组中的儿童随机抽取 10 0名儿童 ,在接种后 2～ 3d进行随访 ,观察接种甲肝减毒活疫苗后不良反应情况。于接种疫苗后 3个月和 12个月分别采集实验组和对照组部分观察对象血清标本 ,检测抗 HAV。结果显示 :实验组中的 10 0名儿童接种疫苗后 ,未见接种局部有明显红肿热痛、皮疹等反应 ,体温无明显增高 ,疫苗的安全性良好。实验组 3个月抗 HAV阳转率为 84 10 % ,1年阳性率为86 39% ,说明疫苗的免疫原性良好。在滴度为 10 6 5TCID50 /ml的剂量下 ,可推广使用。     

HAV H2株不同代次减毒活疫苗的免疫应答和接种反应

将132名甲型肝炎易感儿童随机分为3个组。每组44人。第1组儿童接种H_2M_(20)K_16疫苗,第2组接种H_2M_(20)K_7疫苗。全程接种1针,皮下注射,剂量为10~(6·5)TCID_(50)/1ml。第3组为对照组不接种疫苗。两组疫苗接种均安全。免后1～2个月的抗-HAV阳转率均达80％以上。在观察地区发生甲型肝炎流行时,两组疫苗的保护率分别为100.00％和80.02％。说明在甲型肝炎流行季节前接种H_2M_(20)K_(16)或H_2M_(20)K_7疫苗均可达到有效控制甲型肝炎的流行。     

甲型肝炎灭活疫苗在大学生中加强免疫的效果研究

目的 评价甲型肝炎（甲肝）灭活疫苗在成年人中加强免疫的效果和安全性。方法 选择参加健康成年人甲肝灭活疫苗和冻干甲肝减毒活疫苗随机双盲临床试验,基础免疫前甲肝抗体阴性并完成1针甲肝灭活疫苗或减毒活疫苗的大学生作为研究对象,加强免疫1针甲肝灭活疫苗,免疫前、免疫后28 d采血,检测抗甲肝病毒抗体滴度≥20 mIU/ml为阳性。结果 加强免疫前甲肝灭活疫苗组和减毒活疫苗组GMC分别为70.80 mIU/ml、50.12 mIU/ml;阳性率分别为94.7%、65.0%。加强免疫1针甲肝灭活疫苗后,两组的抗体阳性率均为100.0%,灭活疫苗组和减毒活疫苗组GMC分别为2 816.09 mIU/ml、2 654.55 mIU/ml。结论 接种1针甲肝灭活疫苗或减毒活疫苗3年后,甲肝抗体GMC和阳性率均有不同程度降低,灭活疫苗优于减毒活疫苗,两组进行1针灭活疫苗的加强免疫效果明显。     

Safety enhancement of a genetically modified live rabies vaccine strain by introducing an attenuating Leu residue at position 333 in the glycoprotein

To improve the safety of genetically modified live rabies vaccine strains, most studies have utilized an attenuating Arg-to-Glu mutation at position 333 in the glycoprotein (G333), which is responsible for attenuation of the live vaccine strain SAG2. The Glu residue requires two nucleotide substitutions to revert to pathogenic Arg, thus significantly lowering the probability of pathogenic reversion caused by the Glu-to-Arg mutation at G333. However, only one nucleotide substitution is sufficient to convert the Glu residue to another pathogenic residue, Lys, and thereby to cause pathogenic reversion. This indicates a potential safety problem of SAG2 and the live vaccine candidates attenuated by Glu at G333. In this study, aiming to solve this problem, we examined the utility of a Leu residue, which requires two nucleotide substitutions to be both Arg and Lys, as an attenuating mutation at G333. Using a reverse genetics system of the live vaccine strain ERA, we generated ERA-G333Leu by introducing an Arg-to-Leu mutation at G333. Similar to ERA-G333Glu, which is attenuated by an Arg-to-Glu mutation at G333, ERA-G333Leu did not cause obvious clinical signs in 6-week-old mice after intracerebral inoculation. Importantly, after 10 passages in suckling mouse brains, ERA-G333Glu acquired a pathogenic Lys or Arg at G333 and a high level of lethality in mice, whereas ERA-G333Leu retained the attenuating Leu at G333 and only showed a modest level of virulence probably caused by a mutation at G194. In addition, ERA-G333Leu and ERA-G333Glu induced neutralizing antibody response and protective immunity in mice with similar efficiencies. The results demonstrate that, compared to ERA-G333Glu, ERA-G333Leu is more stably attenuated, also indicating the high utility of a Leu residue as an attenuating mutation at G333 in the development of live rabies vaccine strains with a high level of safety.     

Generation and characterization of a genetically modified live rabies vaccine strain with attenuating mutations in multiple viral proteins and evaluation of its potency in dogs

Live rabies vaccines have advantageous features that can facilitate mass vaccination for dogs, the most important reservoirs/transmitters of rabies. However, some live vaccine strains have problems in their safety, namely, risks from the residual pathogenicity and the pathogenic reversion of live vaccine strains. The reverse genetics system of rabies virus provides a feasible option to improve the safety of a live vaccine strain by, for example, artificially introducing attenuating mutations into multiple viral proteins. It was previously demonstrated in separate studies that introduction of amino acid residues Leu at position 333 in the viral glycoprotein (G333), Ser at G194, and Leu/His at positions 273/394 in the nucleoprotein (N273/394) enhance the safety of a live vaccine strain. In this study, to test our hypothesis that combinational introduction of these residues would significantly increase the safety level of a vaccine strain, we generated a novel live vaccine candidate, ERA-NG2, that is attenuated by mutations at N273/394 and G194/333, and we examined its safety and immunogenicity in mice and dogs. ERA-NG2 did not cause any clinical signs in mice after intracerebral inoculation. After 10 passages in suckling mouse brains, ERA-NG2 retained all of the introduced mutations except the mutation at N394 and the highly attenuated phenotype. These findings indicate that the ERA-NG2 is highly and stably attenuated. After confirming that ERA-NG2 induced a virus-neutralizing antibody (VNA) response and protective immunity in mice, we immunized dogs intramuscularly with a single dose (10^5-7 focus-forming units) of ERA-NG2 and found that, at all of the tested doses, the strain induced a VNA response in dogs without inducing any clinical signs. These findings demonstrate that ERA-NG2 has a high level of safety and a substantial level of immunogenicity in dogs and thus is a promising live vaccine candidate that can facilitate vaccination in dogs.     

Generation of a novel live rabies vaccine strain with a high level of safety by introducing attenuating mutations in the nucleoprotein and glycoprotein

The current live rabies vaccine SAG2 is attenuated by only one mutation (Arg-to-Glu) at position 333 in the glycoprotein (G333). This fact generates a potential risk of the emergence of a pathogenic revertant by a back mutation at this position during viral propagation in the body. To circumvent this risk, it is desirable to generate a live vaccine strain highly and stably attenuated by multiple mutations. However, the information on attenuating mutations other than that at G333 is very limited. We previously reported that amino acids at positions 273 and 394 in the nucleoprotein (N273/394) (Leu and His, respectively) of fixed rabies virus Ni-CE are responsible for the attenuated phenotype by enhancing interferon (IFN)/chemokine gene expressions in infected neural cells. In this study, we found that amino acid substitutions at N273/394 (Phe-to-Leu and Tyr-to-His, respectively) attenuated the pathogenicity of the oral live vaccine ERA, which has a virulent-type Arg at G333. Then we generated ERA-N273/394-G333 attenuated by the combination of the above attenuating mutations at G333 and N273/394, and checked its safety. Similar to the ERA-G333, which is attenuated by only the mutation at G333, ERA-N273/394-G333 did not cause any symptoms in adult mice after intracerebral inoculation, indicating a low level of residual pathogenicity of ERA-N273/394-G333. Further examination revealed that infection with ERA-N273/394-G333 induces IFN-β and CXCL10 mRNA expressions more strongly than ERA-G333 infection in a neuroblastoma cell line. Importantly, we found that the ERA-N273/394-G333 stain has a lower risk for emergence of a pathogenic revertant than does the ERA-G333. These results indicate that ERA-N273/394-G333 has a potential to be a promising candidate for a live rabies vaccine strain with a high level of safety.     

2004-2013年河南省脊髓灰质炎疫苗 相关麻痹型病例分析

摘要:目的　了解河南省疫苗相关麻痹型脊髓灰质炎（Vaccine-Associated Paralytic Poliomyelitis,VAPP）病例发生情况,为其防控策略制定提供科学依据。方法　对河南省2004-2013年的VAPP病例进行描述性分析。结果　河南省2004-2013年共发生VAPP病例19例,VAPP发生率为0.14/100万,首剂服苗VAPP发生率为0.93/100万。VAPP病例男女性别比为8.5∶1,2～6月龄儿童占73.68%。73.68%的病例为首次服苗,服苗至麻痹平均时间间隔为23 d,随访均有残留麻痹。病例便标本病毒分型以Ⅱ型为主。结论　VAPP病例以低月龄、首次服苗儿童为主。应加强接种前预检工作,严格掌握禁忌症。同时适时调整脊灰疫苗免疫策略,减少或避免VAPP的发生。     

减毒活疫苗同时接种建议的分析

随着疫苗种类的增多,合理安排免疫程序显得尤为重要,其中同时接种是保证儿童按免疫程序接种的一项重要策略。但对于同时接种减毒活疫苗,国内外不同文献却给出了不同建议。现通过搜集、整理《中华人民共和国药典》三部（2010版）、世界卫生组织关于疫苗的立场文件和美国免疫实施咨询委员会的建议,并提供部分支持性研究,对减毒活疫苗同时接种建议进行综述。