两种剂量乙肝血源疫苗免疫新生儿的效果比较

<正> 乙肝血源疫苗20μg阻断乙肝病毒母婴传播的效果,已有明确报道。因血源疫苗价格昂贵,用低剂量免疫儿童,可获良好抗体反应。本文试用10μg与20μg两种剂量免疫新生儿,比较两种剂量抗体反应,探讨其用于阻断母婴传播的可能性。     

新生儿单纯乙型肝炎血源疫苗的免疫持久性和远期保护效果

目的 掌握我国新生儿单纯接种乙型肝炎血源疫苗后的免疫持久性和远期预防效果；观察新生儿免疫较长时间后是否需加强免疫。方法 在湖南湘潭市等4个乙型肝炎疫苗试点区间，对1986－1988年出生并接种乙型肝炎血源疫苗的新生儿，连续14－15年按免疫儿年龄分层随机抽样采血随访，累计随访21680人次，观察免疫儿HBsAg、抗－HBs和抗－HBc的动态变化。结果 新生儿单纯乙型肝炎血源疫苗全程基因免疫后，在15年随访中没有加强免疫，各试点区免疫儿童HBsAg携带率低于1．66％，携带率没有随免疫后的延长而增加；阻断HBV慢性感染的效果持续在90％左右（95％可信限为：83．1％－97．2％）；免疫后不同年限间HBsAg携带率、HBV感染率和保护效果差异均无显著性（P＞0．05）。免疫儿抗－HBs阳性率随免疫后年限延长而逐年明显下降，至第9－10年下降为40％－50％，之后数年内下降幅度不大，至免疫后13－14年抗－HBs阳性率维持在30％－42％；抗－HBs滴度下降了90％。结论 新生儿单纯乙型肝炎疫苗接种后抗－HBs阳性率与滴度的下降不影响其远期预防效果；就群体而言，新生儿及时完成全程免疫后，无需加强免疫可有效阻断HBV感染后成为HBsAg慢性携带者，而很有可能终生受益。     

CpG ODN联合乙型肝炎疫苗与乙型肝炎疫苗免疫效果对比研究

目的探讨CpG ODN乙型肝炎疫苗与市售乙型肝炎疫苗对Balb/c小鼠的免疫作用效果。方法将乙肝疫苗、乙肝疫苗+100μgCpG ODN分别肌肉注射到4～6周龄,16～18g Balb/c小鼠体内,于第1次免疫后28d以同样剂量加强免疫1次。分别于第1次免疫后28、42、63 d收集小鼠血清,用ELISA方法检测抗HBs IgG抗体。结果实验组产生的抗HBs IgG与对照组HBsIgG相比P<0.05,具有显著性差异。28、42、63 d抗HBs IgG分别是对照疫苗的114倍、4.73倍、5.41倍以上。结论 CpG ODN能够显著增强小鼠对乙肝疫苗的免疫应答,在较短时间内显著的提高乙肝抗体的产生水平,免疫效果是乙肝疫苗的5倍以上。     

细胞免疫和遗传因素对乙型肝炎疫苗阻断母婴传播效果的影响

目的比较接种重组乙肝疫苗后不同体液免疫应答高危儿童的细胞免疫反应特点,进一步探讨母婴阻断失败、无应答的机理。方法124名母亲HBsAg和HBeAg双阳性的新生儿按常规乙肝的免疫程序接种重组CHO和酵母乙肝疫苗,于第1针免后3、7、12月检测HBsAg和抗-HBs,判定免疫成功或失败的新生儿,首针后60～120月(平均80月)再次检测HBsAg和抗-HBs指标,选取8名免疫重组乙肝疫苗母婴阻断失败儿童、4名免后无应答抗体反应的儿童和11名母婴阻断成功的儿童采集静脉血样,分离淋巴细胞,应用ELISPOT方法检测产生IL-2斑点形成细胞的数量,并对斑点数和表面抗体滴度的相关性进行比较,同时分析HLA-A、-B、DRB1和DQB1等位基因的多态性。结果(1)124名研究对象中有77．4％的儿童可产生保护性表面抗体,成功阻断母婴传播;13．7％的人免疫失败,感染乙肝;8．9％的儿童则对乙肝疫苗呈无应答状态。(2)免疫成功组产生IL-2细胞数(55．2±42．22)显著高于免疫失败组(3,75±3．24)和抗体无应答组(6．75±3．59),P<0．01。(3)儿童免疫乙肝疫苗后的表面抗体滴度与经乙肝疫苗诱导产生的特异性分泌IL-2的T细胞数量呈显著性正相关(r =0．601,P<0．01)。(4)HLA-B*48在对酵母乙肝疫苗无应答的儿童中占有25％的频率,显著高于免疫成功(2．2％)和失败的儿童(0％),P<0．05。对CHO疫苗无应答儿童的HLA-DRB1*15的频率显著高于免疫成功和失败的儿童(P<0．05)。结论乙肝疫苗母婴阻断失败和免后抗体无应答儿童的细胞免疫应答显著低于阻断成功的儿童,并且可能与遗传因素有关。     

乙型肝炎疫苗接种者免疫应答状况分析

<正>目前乙肝疫苗接种重点是新生儿、血液制品使用者及与传染源密切接触的人群,但对一般人群的应用价值尚需进一步研究.我们对乙肝疫苗接种者的免疫应答状况及有关因素进行了分析,报告如下:1 材料和方法1.1 接种对象 5项乙肝血清学指标全部阴性者有203人,其中男性142人,女性61人.年龄21-60岁,平均年龄42.5岁.1.2 接种方法 分每人70μg和每人90μg两种剂量组.前者按30—30—10μg,后者按30—30—30μg分三次上臂三角肌注射.两组均按0—1—6月免疫程序接种.疫苗为卫生部上海生物制品研究所产品.1.3 抗HBs抗体测定 疫苗第三针接种后三个月采血分离血清,采用上海实业科华生物技术有限公司产品作ELISA检测,以抗HBs阳性率反映抗体应答能力.2 结果2.1 乙肝疫苗接种者的免疫应答 如表1所示,203例成人乙肝疫苗接种后产生抗HBs者140例,总应答率达(69.0%).男性应答率(70.4%)与女性(65.5%)无明显差异(P>0.05).按不同年龄组分析,发现随年龄增长,应答能力逐渐减弱;年龄与应     

季节性流感裂解疫苗在小鼠中半数有效剂量ED50a的测定

目的探讨季节性流感疫苗在小鼠中的免疫原性及其使50％小鼠血凝抑制抗体滴度（HI）达到40的血凝素（HA）有效剂量（ED50。）。方法以我国2008—2009年度季节性流感裂解疫苗为模式,将该疫苗中针对甲型流感病毒HlNl与H3N2两种组分按照HA不同剂量免疫小鼠,通过比较1针免疫与2针免疫所产生的Hl抗体强度探讨季节性流感疫苗在小鼠中的免疫原性,确定疫苗免疫程序;此后,观察两种疫苗组分免疫小鼠后的HI抗体动力学,确定HI抗体产生的高峰期;最后,使用HA不同剂量免疫小鼠,在HI抗体高峰期测定使50％小鼠HI抗体滴度达到40的HA有效剂量（ED50。）。结果季节性流感疫苗1针与2针免疫结果显示,两种疫苗组分1针免疫可在小鼠中产生HI抗体滴度范围为10～120,2针免疫可以使HI抗体滴度为1针免疫的10～100倍;HI抗体动力学研究表明,两种疫苗组分1针免疫后第28～35天为HI抗体产生的高峰期;该高峰期的ED50‘测定结果表明,两种疫苗组分使50％小鼠HI抗体滴度达到40的HA有效剂量（ED50。）均为1．5μg。结论季节性流感疫苗在小鼠中具有良好的免疫原性,1针免疫后第28～35天为抗体产生的高峰期,使50％小鼠HI达到40的HA有效剂量为1．5μg,为建立以季节性流感疫苗为参考的免疫保护评价体系奠定了基础。     

豫北地区嗜水气单胞菌灭活疫苗的制备及免疫效果的研究北大核心CSCD

目的:选取毒力因子多、毒性强的嗜水气单胞菌株(Aeromonas hydrophil)制成灭活疫苗,研究疫苗的免疫保护效果。方法:采用甲醛灭活制备疫苗,对银鲫进行腹腔注射,设立免疫组和对照组,然后进行血清抗体效价检测、病理切片分析和攻毒保护试验。结果:银鲫在经注射免疫后,各免疫时间均有抗体产生,抗体效价在第6周检测时达到高峰,而对照组在整个试验过程中均没有检测到抗体;病理切片也表明,该疫苗能够对鲫鱼靶器官产生很好的保护作用;攻毒保护试验中,免疫组的免疫保护率达100%,且免疫保护期长达6个月以上。结论:嗜水气单胞菌灭活疫苗对银鲫有显著的免疫保护效应,可作为预防细菌性败血症感染的疫苗。     

b型流感嗜血杆菌结合疫苗接种后婴幼儿安全性和免疫原性研究

目的 评价b型流感嗜血杆菌结合疫苗(Hib-TT)安全性和免疫原性.方法 分别采用Hib-TT试验疫苗和对照疫苗3针免疫接种3～5月龄婴幼儿,观察疫苗安全性,并采用定量ELISA法分别测定免疫前、免疫后和加强免疫后血清特异性IgG抗体浓度.结果 实验疫苗和对照疫苗两组间不良反应总发生率(实验疫苗组为23.85％,对照疫苗组为31.40％)差异无统计学意义(x2=0.5,P＞0.05),发热性总不良反应率分别为22.3％和31.3％,中、强发热反应率分别为3.67％和4.48％,差异无统计学意义；实验疫苗受试者局部红、肿、硬结等不良反应率为1.22％.实验疫苗3剂免疫后受试者血清抗Hib PRP IgG抗体平均几何浓度(GMC)为6.6786 μg/ml,对照疫苗组血清抗体GMC为7.5346 μg/ml,两组间抗体GMC差异无统计学意义(x2=0.147,P=0.702)；加强免疫1剂后,实验疫苗组受试者血清抗体GMC从加强免疫前的2.6396 μg/ml上升为6.2044μg/ml.结论 实验疫苗接种3～5月龄婴幼儿具有良好的安全性.用间隔1个月、3剂次接种的基础免疫程序能诱导该年龄组受试者产生长期保护水平的血清特异性抗体,加强免疫1剂后能诱导机体产生免疫记忆反应.     

电转染技术结合初免后加强免疫策略增强结核杆菌核酸疫苗免疫原性的研究

目的研究电转染技术结合初免后加强免疫策略能否增强结核杆菌核酸疫苗的免疫原性。方法将编码结核杆菌的Ag85A和ESAT-6蛋白抗原的基因分别插入到质粒pVAX1载体中，构建成HG85和HG6两种核酸疫苗。每只BALB／c小鼠肌肉注射10μg核酸疫苗，同时于注射部位施加方型波电脉冲促进质粒DNA体内转染；进行3次初免，再用相应蛋白质抗原或卡介苗加强免疫。结果肌肉注射10μg核酸疫苗加电转染能诱导出与不用电转染接种100μg核酸疫苗相似或更强的抗体免疫应答。初免后采用相应蛋白加强后小鼠产生的免疫应答偏向于TH2型，血清特异性抗体的几何平均滴度比加强前提高5—76倍。而用卡介苗加强免疫，产生的免疫应答偏向TH1型。结论采用电转染技术结合蛋白质或卡介苗加强免疫策略，能显著增强结核杆菌核酸疫苗在动物体内的免疫原性。     

EHF疫苗不同途径免疫后血清及黏膜抗体应答情况

目的探讨EHF疫苗经不同剂量和途径免疫后血清IgG及黏膜IgA产生情况,以探讨合适的免疫剂量和接种途径。方法以不同剂量EHF双价灭活疫苗分别经皮下和灌胃免疫小鼠,共3次（第0、5、10天）,末次接种后5d收集血清和小肠冲洗液,用间接免疫荧光法（IFA）检测血清EHF IgG抗体和小肠冲洗液IgA抗体。结果皮下注射能诱导血清特异性IgG和黏膜IgA的产生,灌胃免疫未见抗体产生,1．4 TCID50的EHF疫苗剂量在皮下注射组血清IgG和小肠冲洗液IgA有100％阳性率。结论EHF疫苗皮下注射能诱导血清特异性IgG和黏膜IgA的产生,1．4 TCID50的剂量为较佳剂量。     

乙肝疫苗联合乙肝免疫球蛋白对阻断母婴垂直传播乙型肝炎病毒的临床分析

目的探讨孕妇产前用乙肝免疫球蛋白（HBIG）与乙型肝炎疫苗联合免疫阻断母婴传播的效果。方法将504例HBsAg（＋）孕妇分为A（预防组）,B（对照组）两组。A组：246名HBsAg阳性孕妇孕晚期每月分别注射基因重组型乙肝疫苗10μg、HBIG200IU（200IU/ml）,新生儿出生后采股静脉血,同时在出生后24h内注射HBIG200IU,然后在0、1、6月龄接种基因重组型乙肝疫苗,每次10μg。B组：258例产前未注射HBIG和基因重组型乙肝疫苗的HBsAg阳性孕妇,其所生新生儿在0、1、6（30μg、30μg、30μg）月龄只用基因重组型乙肝疫苗免疫。A、B两组婴儿都分别在0、3、6、9、12、24月龄静脉采血,用酶联免疫吸附试验（ELISA）检测HBV标志物,同时随访。结果A组的宫内感染率为3.25%,B组为4.16%,差异无统计学意义（χ^2=1.43,P〉0.05）。A组没有发生慢性HBV感染的婴儿,而B组中有7例婴儿发生慢性HBV感染,B组婴儿发生慢性HBV的感染率显著高于A组（χ^2=4.41,P〈0.05）。结论产前用HBIG和新生儿HBIG联合免疫可降低慢性HBV感染率,阻断宫内感染的慢性化,提高产程感染的阻断效果。     

Resistance of adults to challenge with influenza A wild-type virus after receiving live or inactivated virus vaccine.

The efficacy of live attenuated cold-adapted (ca) reassortant influenza A H3N2 and H1N1 virus vaccines against experimental challenge with homologous wild-type virus 7 months after vaccination was compared with that of licensed inactivated virus vaccine in 106 seronegative (hemagglutination-inhibiting antibody titer less than or equal to 1:8) college students. The live attenuated virus vaccines induced as much resistance against illness as did the inactivated vaccine. Vaccine efficacy, measured by reduction in febrile or systemic illness in vaccines, compared with that in controls was 100% for ca H3N2 vaccine, 84% for inactivated H3N2 vaccine, 79% for ca H1N1 vaccine, and 67% for inactivated H1N1 vaccine. Less protection was conferred against upper respiratory tract illness; there was 50 and 77% protection in ca and inactivated H3N2 vaccines, respectively, but there was no protection in ca or inactivated H1N1 vaccinees. The duration, but not the magnitude, of H1N1 wild-type virus shedding in both ca and inactivated vaccinees was significantly reduced compared with controls. In contrast, a significant reduction in the duration and magnitude of H3N2 virus shedding was observed in ca vaccinees but not in inactivated vaccines. After wild-type virus challenge, live ca virus vaccinees demonstrated resistance at least as great 7 months postvaccination as did inactivated virus vaccinees. These observations indicate that live virus vaccines may be a satisfactory alternative to inactivated vaccines for healthy persons.     

Multicomponent Meningococcal Serogroup B Vaccine (4CMenB; Bexsero®): A Review of its Use in Primary and Booster Vaccination

Multicomponent meningococcal serogroup B vaccine (4CMenB; Bexsero^®) is a unique vaccine containing four main immunogenic components: three recombinant proteins combined with outer membrane vesicles derived from meningococcal NZ98/254 strain. After three doses of 4CMenB (administered at 2, 3, and 4 months or 2, 4, and 6 months of age) in vaccine-naive infants, the majority of infants had seroprotective human complement serum bactericidal assay (hSBA) antibody titers against the meningococcal serogroup B test strains selected to be specific for the vaccine antigens in randomized, open-label or observer-blind, multicenter, phase IIb or III trials. In extensions to the phase III trial, two doses of 4CMenB administered between 12 and 15 months of age in vaccine-naive infants, and a single booster dose of 4CMenB administered at 12 months of age in vaccine-experienced infants, also elicited robust immunogenic responses. In a phase IIb/III trial, the majority of adolescents (aged 11–17 years) achieved seroprotective hSBA antibody titers against meningococcal serogroup B test strains after two doses of 4CMenB, and a third dose did not appear to add any extra protection. In adults who were potentially at an increased risk of occupational exposure to meningococcal isolates, seroprotection rates were high after one dose of 4CMenB and increased further after two or three doses in a small noncomparative, two-center, phase II trial. The reactogenicity of 4CMenB was generally acceptable in clinical trials. However, the vaccine was associated with more solicited systemic adverse events (particularly fever) in infants when coadministered with routine infant vaccines than when these vaccines were administered alone. In conclusion, 4CMenB effectively elicited immune responses against meningococcal serogroup B test strains selected to be specific for the vaccine antigens in infants, adolescents, and adults.     

不同剂量乙肝疫苗与HBIG联合免疫阻断HBV母婴传播的效果对比

目的 探讨10 μg和20 μg乙肝疫苗与HBIG联合免疫阻断HBV母婴传播的效果.方法 124例HBsAg阳性孕妇所生的婴儿随机分为两组,即10 μg乙肝疫苗组和20 μg乙肝疫苗组.婴儿于出生6h内及30 d分别注射200 IU HBIG,同时分别于出生24 h内、1个月及6个月注射3次10 μg或20 μg重组酵母乙肝疫苗.检测婴儿出生时以及1岁时血清HBV标志物.结果 两组新生儿血清HBsAg、HBeAg及抗-HBe阳性率与滴度之间差别均无统计学意义（P＞0.05）.所有新生儿血清HBV DNA水平均小于检测下限（500 U/ml）.出生12个月时,所有124例婴儿血清HBsAg和HBeAg检测结果均为阴性;血清HBV DNA水平均在检测下限以下;10 μg和20 μg乙肝疫苗组血清抗-HBs阳性率分别为90.3％和96.8％,差异无统计学意义（P＞0.05）;抗-HBs水平分别为325.5±342.2 mIU/ml和463.7±353.3 mIU/ml,后者显著高于前者（P=0.01）.而且,20 μg乙肝疫苗组产生高应答抗-HBs（＞ 100 mIU/ml）的比例显著高于10μg乙肝疫苗组（P =0.035）.结论 20 μg乙肝疫苗联合HBIG方案阻断HBV母婴传播的效果优于10 μg乙肝疫苗联合HBIG方案.     

Hepatitis B immunization in high risk neonates born from HBsAg positive mothers: comparison between plasma derived and recombinant DNA vaccine

A half dose recombinant hepatitis B vaccine (HBVax II, MSD, 5 micrograms) was investigated for efficacy in the prevention of perinatal hepatitis B virus (HBV) transmission in high risk neonates born from e-antigen positive HBsAg carrier mothers as compared to the half-standard dose regimen of plasma derived hepatitis B vaccine (HBVax, MSD, 10 micrograms). Forty infants born to carrier mothers were given hepatitis B immune globulin (HBIG) 100 IU intramuscularly immediately after birth, combined with either the recombinant or plasma derived hepatitis B vaccine. The infants were randomly divided into two groups of 20 infants each. The plasma derived vaccine (10 micrograms) was given to group I, while infants in group II received the recombinant vaccine (5 micrograms) at birth, 1 and 6 months of age. There were no statistically significant differences in the efficacy and the seroconversion rate of these two combined prophylaxis regimens. The protective efficacy rate of both kinds of HBV vaccine was found to be 94.6 and 89.2 percent in group I and group II respectively. At twelve months of age, the anti-HBs seroconversion rates were 95.0 percent in group I and 84.2 percent in group II. However, the geometric mean titres in group I (179.55 mIU/ml) was significantly higher than those in group II (42.2 mIU/ml) but the anti-HBs titre was still above protective level (10 mIU/ml) in most of the infants.(ABSTRACT TRUNCATED AT 250 WORDS)     

Critical Analysis of Compositions and Protective Efficacies of Oral Killed Cholera Vaccines

Two cholera vaccines, sold as Shanchol and Dukoral, are currently available. This review presents a critical analysis of the protective efficacies of these vaccines. Children under 5 years of age are very vulnerable to cholera and account for the highest incidence of cholera cases and more than half of the resulting deaths. Both Shanchol and Dukoral are two-spaced-dose oral vaccines comprising large numbers of killed cholera bacteria. The former contains Vibrio cholerae O1 and O139 cells, and the latter contains V. cholerae O1 cells with the recombinant B subunit of cholera toxin. In a field trial in Kolkata (India), Shanchol, the preferred vaccine, protected 45% of the test subjects in all of the age groups and only 17% of the children under 5 years of age during the first year of surveillance. In a field trial in Peru, two spaced doses of Dukoral offered negative protection in children under 5 years of age and little protection (15%) in vaccinees over 6 years of age during the first year of surveillance. Little is known about Dukoral''s long-term protective efficacy. Both of these vaccines have questionable compositions, using V. cholerae O1 strains isolated in 1947 that have been inactivated by heat and formalin treatments that may denature protein. Immunological studies revealed Dukoral''s reduced and short-lived efficacy, as measured by several immunological endpoints. Various factors, such as the necessity for multiple doses, poor protection of children under 5 years of age, the requirement of a cold supply chain, production costs, and complex logistics of vaccine delivery, greatly reduce the suitability of either of these vaccines for endemic or epidemic cholera control in resource-poor settings.     

Immunogenicity of a yeast-recombinant hepatitis B vaccine in high-risk children

Horizontal transmission of hepatitis B virus (HBV) from illicit drug users to their contacts, including young children, can be prevented by active immunization against HBV. Yeast-recombinant hepatitis B vaccines are now available for this purpose, but their potential efficacy in such high-risk contacts has not yet been evaluated. Therefore we gave 20 mcg of a recombinant yeast-derived hepatitis B vaccine to 38 children who were at high risk for HBV infection because they had been institutionalized in a community for drug users in which 8.7% of the occupants are carriers. After third dose of vaccine (at 0, 1, and 6 months), all children had anti-HBs responses with titers of 10 mIU/ml or more, with 81% showing responses greater than 1,000 mIU/ml. At 12 months, the percentage of anti-HBs-positive children was 100%, and the percentage of children with anti-HBs higher than 1,000 mIU/ml was 56%. None of the children developed HBV infection during follow-up. Hence the recombinant vaccine was immunogenic, with percentages of seroconversion and anti-HBs titers comparable with those attained in other categories of high-risk children with plasma-derived vaccines.     

Development Of An Inactivated Vaccine Against Infectious Laryngotracheitis (ILT) - serological and protection studies

The strain of infectious laryngotracheitis (ILT virus utilised for these vaccine-development studies was isolated from an outbreak of the disease in Hungary. Inactivating agents tested included beta-propio-lactone, methyleneimine, ethyleneimine EI and formalin. ILT virus preparations inactivated with EI appeared to be the most antigenic when inoculated into chickens in the absence of adjuvant. For formulation of a trial oil-emulsion ILT vaccine for experimentation, ILT virus inactivated with 1200 mug/ml of EI was mixed with an equal volume of 50% incomplete Freund's adjuvant and then homogenised. Experimental vaccination of chickens with inactivated ILT vaccine elicited satisfactory serological response and protection to challenge both under laboratory and field conditions. Although only minor increases in antibody titres could be achieved by repeated vaccination with inactivated ILT vaccine at 2 to 5 weeks after primary vaccination at 10-weeks-old with attenuated or inactivated ILT vaccines, the protection conferred by vaccination with a single dose of the trial inactivated ILT vaccine appeared to be effective for at least 12 months. Hence, there would appear to be potential for inactivated-ILT vaccines in control of ILT, especially on sites that are regularly affected by this infection.     

Field evaluation of the efficacy and immunogenicity of recombinant hepatitis B vaccine without HBIG in newborn Vietnamese infants

A study involving more than 2,000 infants was conducted in Vietnam to assess the field effectiveness and immunogenicity of recombinant hepatitis B vaccine given at birth, 1 month, 2 months, without concomitant hepatitis B immune globulin (HBIG). All received a 5 microg dose of H-B-VAX II at birth. Infants born to non-carrier mothers (Group 1; N = 1798) then received 2.5 microg doses at 1 and 2 months of age, while infants of HBeAg-negative (Group 2; N = 125) or HBeAg-positive (Group 3; N = 88) carrier mothers received 5 microg doses. No Group 1 or 2 vaccinees were infected. In Group 3, 12 (14.6%) of 82 infants did become infected (estimated efficacy 84%). 98.0-98.6% of uninfected infants who were tested for anti-HBs developed a seroprotective concentration > or = 10 IU/L. In hyperendemic Vietnam, where routine maternal screening and passive-active prophylaxis of high-risk infants with vaccine plus HBIG is not feasible, administration of vaccine alone to all newborns may control effectively HBV infection.     

Homotypic and heterotypic antibody response in infants to adenovirus vaccine

Summary Two or three doses of inactivated monkey kidney tissue culture propagated adenovirus vaccine containing types 3, 4 and 7, or three doses of placebo fluid were administered to 271 infants 3 to 12 months of age. Vaccination was not associated with any clinical reactions.The first dose of vaccine produced a poor response, whereas the second and third doses stimulated high levels of neutralizing antibody to types 3, 4 and 7. The response in infants without pre-existing antibody did not deviate significantly from that in initially antibody-positive infants. Three doses of vaccine were found to produce neutralizing antibody in 97—100% of the infants. Antibody persisted for at least one year in 70—100% of 35 infants studied, although the titers decreased substantially. Low levels of heterotypic antibody to types 14 and 21 developed in, respectively, 76% and 18% of initially antibody-negative infants after two or three doses of vaccine.The neutralizing antibody response observed 6 months after administration of one dose of vaccine was substantially higher than that found one month after the first injection.