中山市健康人群乙肝血清学监测情况分析

目的 了解乙肝疫苗接种效果情况，进而探讨如何更好地实行免费接种乙肝疫苗，确保接种质量。方法 随机抽取152名新生儿和1岁以上健康人群2495名，应用酶联免疫法对其血清进行HBsAg和anti．HBsAg检测。结果 152名新生儿，抗-HBs阳性141人，阳性率为92．7％。HBsAg阳性0人。2495名1岁以上健康人群，抗-HBs阳性1199人，阳性率为48．1％，HBsAg阳性259人，阳性率为10．4％。1～18岁844人，HBsAg阳性10人，阳性率为1．2％。18岁以上1651人，HBsAg阳性249人，阳性率为15．1％。结论 对新生儿及时进行乙肝疫苗全程免疫，能提高新生儿对乙肝的免疫力，预防乙肝。接种乙肝疫苗、提高接种质量能提高易感人群对乙肝的免疫力。降低人群乙肝感染率。1岁以上健康人群抗-HBs阳性率偏低，存在感染乙型肝炎病毒的危险。     

新生儿不同时期静脉血HBsAg含量对HBV母婴传播阻断失败的预测研究

目的探讨HBV慢性感染孕妇新生儿出生后不同时期静脉血HBsAg含量变化对ItBV母婴传播阻断失败的预测价值。方法以HBsAg、HBeAg双阳性、血清HBVDNA含量≥10^5拷贝／ml慢性HBV感染孕妇所娩新生儿150例为研究对象,出生后立即注射乙肝免疫球蛋白200Iu,并按0、1和6个月程序接种乙肝疫苗10～20μg。分别于新生儿出生时、生后1个月、生后7个月采取静脉血检测HBV血清学指标,分析新生儿不同时期静脉血HBsAg含量对HBV母婴传播阻断失败的预测。结果共有11例新生儿发生HBV母婴阻断失败。新生儿出生时、生后1个月、生后7个月HBsAg阳性率分别为41．26％、10．49％、7．69％,HBeAg阳性率分别为97．90％、65．75％、13．29％。以出生时I-IBsAg≥O．05和HBsAg≥1IU／ml预测HBV母婴传播阻断失败,阳性预测价值分别为18．64％和70％;生后1个月HBsAg〉~O．05和HBsAg≥1IU／ml的阳性预测价值分别为73．33％和100％。结论出生时静脉血HBsAg含量≥1IU／ml时应高度怀疑HBV母婴传播的失败。生后1个月HBsAg≥1IU／ml对母婴传播阻断失败有高度的预测价值,如何提高出生时和生后1个月静脉血HBsAg阳性新生儿的HBV感染阻断率是以后研究的重点。     

新生儿静脉血与脐带血及孕妇静脉血HBV病原学标记物相关性研究

目的 探讨慢性HBV感染孕妇所生新生儿脐带血与静脉血HBV标志物状况的一致性和相关性,以及与孕妇HBV感染标志物的相关性.方法 以HBsAg、HBeAg双阳性且HBV DNA＞1 ×105拷贝/ml孕妇及新生儿为研究对象,孕妇分娩前采集静脉血,新生儿于注射乙肝免疫球蛋白、乙肝疫苗前采集静脉血.在清洁和去除脐带表面污染血液,并用酒精消毒后,用注射器采集脐带血.HBsAg、抗HBs、HBeAg、抗HBe采用雅培微粒子化学发光法(美国雅培公司试剂,Abbott Architac i2000)检测,HBV DNA含量经COBAS TagMan HBV DNA定量检测仪检测.结果 共入组孕妇383例及所生新生儿,静脉血和脐带血HBsAg的阳性检出率分别为61.2％和63.9％,HBeAg阳性检出率分别为83.2％和83.5％,HBV DNA阳性检出率分别为56.0％和59.4％,静脉血和脐带血之间均有一致性.静脉血和脐带血间HBsAg、HBeAg和HBV DNA含量的相关性具有统计学意义(r=0.766、0.857、0.692,P＜0.000).新生儿静脉血和脐带血的HBeAg含量与孕妇的HBeAg含量具有相关性(r=0.362,P=0.000;r=0.352,P=0.000),而静脉血和脐带血的HBsAg含量与孕妇血清的HBsAg含量无相关性(r=0.023,P=0.785;r=0.04,P=0.604).结论 慢性HBV感染孕妇所生新生儿脐带血和静脉血HBV标志物状态有良好的一致性,可以以脐带血的HBV标志物反映新生儿静脉血HBV标志物.     

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。     

阻断乙型肝炎病毒父婴传播的研究

目的探讨阻断乙型肝炎（乙肝）病毒父婴垂直传播的有效方法。方法将在北京市海淀区妇幼保健院乙肝母婴阻断门诊就诊的配偶为HBV携带者的孕妇共例61例作为观察对象,22例配偶为乙肝表面抗原和乙肝e抗原双阳性及乙肝病毒脱氧核糖核酸阳性。其中28例孕妇也为乙肝病毒携带者,仅1例孕妇为HBsAg和HBeAg双阳性。对33例本人未检出HBV抗原的孕妇检测乙肝表面抗体定量,对定量较低或阴性的孕妇在孕前或孕期接种国产（基因重组酵母）乙肝疫苗10μg,根据定量接种1—2次。对孕妇也为HBV携带者和孕妇在孕末期前检验血中尚未达到高滴定度保护性抗体乙肝表面抗体者,在孕末期28、32、36w各肌肉注射乙肝免疫球蛋白400IU。观察新生儿生后12h内静脉血乙肝表面抗原和乙肝e抗原及乙肝表面抗体定性,采用酶联免疫法定性测定。结果所有观察新生儿61例生后12h内静脉血乙肝表面抗原和乙肝e抗原均为阴性,以后3、6、12个月复查乙肝表面抗原和乙肝e抗原未发现阳转者。33例母亲未检出HBV的新生儿生后12h内静脉血乙肝保护性抗体乙肝表面抗体均为阳性,28例母亲也为乙肝病毒携带者的新生儿乙肝表面抗体均为阴性。结论对配偶为乙肝病毒携带者的孕妇在孕前或孕期接种乙肝疫苗;对孕妇也为HBV携带者或孕妇在孕末期前检验血中尚未达到高滴定度保护性抗体乙肝表面抗体者,在孕末期肌肉注射较大剂量乙肝免疫球蛋白的措施可基本阻断乙肝病毒父婴垂直传播。     

重组酵母乙肝疫苗对新生儿免疫效果的评价

目的研究新生儿接种国产5μg重组酵母乙肝疫苗的免疫效果及影响因素。方法从东莞市石碣医院预防接种门诊登记的,2005年7～12月出生的,按规定接种程序完成乙肝疫苗接种的新生儿中随机抽取303名进行横断面调查研究。结果新生儿免疫后抗-HBs几何平均滴度（GMT）为（201.36±14.89）mIU/ml。母亲乙肝HBsAg阳性/阴性、母亲乙肝HBeAg阳性/阴性、男/女、是否出生低体重、是否早产、本地/外地的新生儿之间抗-HBs抗体GMT差别无统计学意义（P〉0.05）。抗-HBs阳转率为97.69%,达到卫生部规定的免疫成功率指标（85%）（t=6.19,P〈0.001）;母亲HBsAg阳性/阴性、HBeAg阳性/阴性的新生儿之间抗-HBs阳转率差别有统计学意义。新生儿HBsAg阳性率0.33%,母亲乙肝HBeAg阳性/阴性的新生儿HBsAg阳性率差别有统计学意义（P〈0.05）。免疫后母婴传播阻断保护率为96.16%。结论新生儿接种国产5μg重组酵母乙肝疫苗具有良好的免疫效果,与乙肝免疫球蛋白100 IU联合使用,有良好的母婴传播阻断保护作用。母亲乙肝感染状况（HBsAg、HBeAg阳性）是影响新生儿乙肝抗-HBs阳转率的危险因素;母亲乙肝HBeAg阳性是影响新生儿乙肝疫苗母婴传播阻断保护率的危险因素。     

乙肝免疫球蛋白与乙肝疫苗联合免疫对新生儿预后的影响

目的探讨乙肝免疫球蛋白（HBIG）与乙肝疫苗联合免疫对HbsAg、HbeAg单阳性及双阳性孕妇所生新生儿预后的影响。方法试验组孕妇自怀孕28w起每4w注射HBIG 200IU,新生儿出生8h内、15天各注射HBIG 200IU,同时按0、1、6月顺序接种乙肝疫苗（每次剂量5μg）。对照组新生儿仅按0、1、6月顺序接种乙肝疫苗。观察两组中新生儿HBV感染情况。结果HBV病毒携带者中,HbeAg阴性的试验组与对照组新生儿HBV感染差异无显著性;HbeAg阳性的试验组与对照组新生儿HBV感染差异有显著性。结论应用乙肝免疫球蛋白与乙肝疫苗联合免疫能有效阻断HBV母婴传播的产前和产后感染,并降低宫内感染率,对新生儿预后较好。     

广州市应用乙型肝炎疫苗免疫22年人群血清学效果研究

目的评价广州市长期应用乙型肝炎疫苗（hepatitis B vaccine,HepB）对乙型肝炎（乙肝）免疫防病效果。方法在广州市全市12个区、县级市按照多阶段分层整群抽样法,以家庭为单位对1～59岁人群进行横断面调查分析,包括检测HBsAg、抗-HBs,对HepB接种史及主要乙肝感染危险因素进行问卷调查,评估人群HepB接种率,分析和比较不同年龄组、不同家庭感染状况下接种与未接种HepB人群乙型肝炎病毒感染指标,评价HepB免疫防病效果。结果 1～16岁年龄组乙肝疫苗全程接种率为88.11%（2535/2877）,17～59岁人群有乙肝疫苗免疫史为20.75%（470/2113）。在推行新生儿HepB接种纳入计划免疫管理后出生的1～16岁人群,HBsAg阳性率为1.29%,而出生时尚未开展HepB接种的20～59岁人群HBsAg阳性率为13.72%。1～16岁人群中有HepB接种史人群HBsAg阳性率0.99%,无接种史人群为5.56%,疫苗保护率为82.19%。20～59岁人群接种HepB,基本都不是在新生儿时期,疫苗保护率为52.01%。新生儿接种HepB,母婴乙肝传播阻断率为94.16%,并能有效阻断家庭内水平传播。结论长期实施新生儿接种HepB能控制、消除受种人群乙肝病毒感染,非新生儿人群接种HepB也能显著降低乙肝病毒感染率。     

新生儿乙肝表面抗原阳性的确认及原因分析

目的:明确乙肝表面抗原(HBsAg)阳性新生儿乙肝病毒(HBV)的感染状况并分析其呈现阳性的原因。方法:选取本院儿科住院部检测乙肝病毒标志物(HBV-M)的2 260例接种过乙肝疫苗的新生儿,将HBsAg阳性者立即进行HBsAg定量复检,确认阳性者纳入观察组,阴性者纳入对照组;将观察组依据年龄分为1～7 d组、8～14 d组和15～28 d组;对照组依据临床诊断是否为高胆红素血症分为黄疸组和非黄疸组。知情同意后,观察组进行1～2周HBV-M追踪监测,收集所有新生儿临床诊断结果,HBV-M及总胆红素(TBIL)检测结果,观察组患儿母亲的HBV感染状况等临床资料,分析比较观察组、黄疸组及非黄疸组间总胆红素的差异,观察组与对照组乙肝表面抗体(HBsAb)的差异。结果:经HBsAg定量确认,观察组99例、对照组2 161例;1～7 d组96例、8～14 d组1例、15～28 d组2例;黄疸组526例、非黄疸组1 635例。观察组HBV-M模式主要以单项HBsAg(+)为主,占比62.6%(62/99),其次为HBsAg(+)合并HBsAb(+),占比20.2%(20/99);1～7 d组新生儿阳性检出率最高,占比97.0%(96/99);3例HBeAg阳性者其母亲为乙肝"大三阳",其余患儿母亲HBsAg阴性,后者HBsAg定量测定值为0.11(0.06～0.24)U/ml,均为低值;第1周3例HBeAg阳性者HBV-M模式未变,67例HBsAg均转阴,29例测定值明显降低,并于第2周20例转阴、9例未检。观察组与黄疸组总胆红素差异无统计学意义(P0.05),与非黄疸组差异有统计学意义(P0.05),黄疸组与非黄疸组差异有统计学意义(P0.05)。观察组HBsAb阳性率及其测定值均低于对照组(P0.05)。结论:HBsAg阳性新生儿大多并未感染HBV,其原因是接种乙肝疫苗即刻检测所致,新生儿检测HBV-M最好选择在接种乙肝疫苗2～3周后。     

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 vaccine in the prevention of perinatally transmitted hepatitis B virus infections: initial report of a study in the West Midlands of England

A study was carried out to evaluate the efficacy of hepatitis B vaccine in interrupting perinatal transmission of hepatitis B virus from carrier mothers to their babies. A four-dose schedule was used. Eight of nine babies of e antigen carrier mothers became actively immune when immunisations were started within 48 hr of birth. Effectiveness was reduced if immunisation was delayed. This report includes results from a total of 32 babies, the longest period of follow-up being 2 years. The success of this scheme is comparable to that of more intensive prophylaxis of immunoglobulin either alone or combined with vaccine and should be seriously considered for the babies of all hepatitis B carrier mothers.     

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.     

Quantitative analysis of HBV DNA level and HBeAg titer in hepatitis B surface antigen positive mothers and their babies: HBeAg passage through the placenta and the rate of decay in babies

It is well documented that perinatal transmission is the major cause of chronic HBV infection in China. However, the mechanisms of HBV perinatal transmission are not defined clearly. It is not known whether hepatitis B e antigen can cross the human placenta, and the rate of HBeAg decay in babies with and without HBV breakthrough has not been studied. In this study, HBV serological markers were investigated in 95 hepatitis B surface antigen positive pregnant women. These markers were also studied in the babies at birth and at the age of 6 months and 12 months. The data show that 7.4% (7/95) children were infected with HBV during the first year after birth despite receiving passive-active immunoprophylaxis with hepatitis B immune globulin and hepatitis B vaccine. The surface gene fragment of HBV DNA was cloned and sequenced following PCR amplification in 7 cases of HBsAg positive babies and their mothers. All babies had the same sequences as their mothers, although two babies also had sequences that would produce an amino acid substitution within the "a" determinant. Furthermore, we measured HBeAg titers and HBV DNA levels by using Abbott AxSYM system and LightCycler-based real-time fluorescence quantitative PCR in 54 mother-infant pairs. Thirty-three mothers were HBeAg positive, and 21 mothers were HBeAg negative. Seventy percent (23/33) of neonates from HBeAg-positive mothers were HBeAg positive at birth compared with 0% (0/21) of neonates from HBeAg negative mothers. HBeAg was present at higher titer in the birth sera of the babies with HBV breakthrough than in babies without breakthrough. HBeAg was cleared from the serum in all 19 babies without breakthrough. In 17 of these 19 babies, the HBeAg was cleared within 6 months, and in two babies clearance took 12 months. The mean serum HBV DNA level in the mothers of the 4 infants with HBV breakthrough was significantly higher than in the mothers of babies who did not become infected. In conclusion, this data suggests that HBeAg can cross the human placenta, and disappears from serum within 6 months in most babies. HBV DNA levels in hepatitis B carrier mothers are associated with the failure of HBIG and vaccine immunization, and the additional influence of transmitted HBeAg cannot be excluded.     

Comparative evaluation of the immunogenicity of yeast-derived (recombinant) and plasma-derived hepatitis B vaccine in infants.

The immunogenicity of plasma-derived (HB Vax,MSD) and recombinant hepatitis B virus (Engerix B, SK&F) vaccines was evaluated in infants born to hepatitis B virus carrier mothers. The vaccination was carried out at 1 day, 1 month, and 6 months of age using 10 micrograms of the vaccine given intramuscularly. A total of 83/88 (94.3%) and 74/79 (93.6%) of the infants receiving the plasma-derived vaccine and yeast-derived vaccine showed antibody to hepatitis B surface antigen (anti-HBs). None of the maternal factors studied apart from the HBeAg positivity corellated with vaccine failure. The yeast-derived vaccine gives marginally lower antibody titre than the plasma-derived vaccine. The group-specific anti-"a" antibody was less than 10% of the total anti-HBsAg titre. It was observed that the vaccine alone without prior administration of hepatitis B immunoglobulin is effective in perinatal infection.     

The vaccinal prevention of the HBsAg carrier state among newborn infants]

The paper presents the data on the time course of HBsAg carrier state in babies born to mothers with antigenemia indicating the dependence of the pattern of the antigen carrier state in babies upon the time of its primary detection. The stable (chronic) HBsAg carrier state in babies was shown to be formed after the first 3 months of life which attests to the necessity of using a vaccine against hepatitis B (HB) for prevention of HBsAg carrier state in newborns. The results of epidemiological survey in 185 babies developing HB with the analysis of all possible factors of their infection contraction are presented. The efficacy of the national plasma vaccine against hepatitis B is evaluated in observations of the newborn babies whose mothers were carriers of HBsAg. It was established that in vaccinated babies after 3 injections of the vaccine at 0, 1, and 6 months the rate of antigen detection was 3.3% and that of antibody 80% whereas in babies of the control group these values were 23.7% and 8.0%, respectively.     

Hepatitis B vaccine alone or in combination with anti-HBs immunoglobulin in the perinatal prophylaxis of babies born to HBsAg carrier mothers.

The efficacy of hepatitis B virus (HBV) vaccine alone (group I) or in combination with hepatitis B immunoglobulin (HBIG) (group II) for prevention of perinatal transmission of the virus was assessed in 21 and 24 neonates, respectively. 58 infants who could not be vaccinated constituted the control group. It was observed that in the unvaccinated group approximately 70% of the infants became infected. In both the vaccinated groups, the seroconversion and seroprotection rates (anti-HBs > or = 10 IU/1) were almost similar at 6 months of follow up, but, at 12 months, infants given HBIG and vaccine showed better seroprotection rate (85%) than those given vaccine alone (58.8%). Immune response to the vaccine was also better in both the groups if the mothers were anti-HBe positive. Despite immunization, 14.2% and 25% infants in group I and II, respectively, became chronic carriers if their mothers were HBeAG positive.     

Protective efficacy of hepatitis B vaccines in neonates

A literature search was carried out to investigate the factors that influence the protective efficacy (PE) of hepatitis B vaccines when given to neonates of hepatitis B surface antigen and e antigen positive mothers. Hepatitis B vaccines with either high or low antigen doses are very effective in preventing chronic hepatitis B infection in neonates at risk, but there is evidence that with lower dosages simultaneous use of hepatitis B immune globulin (HBIG) administration is more important than with higher dosages to elicit good protection (PE ≧ 90%). There is also a tendency for lower dosages to confer high PE less consistently, with noticeably greater numbers of chronic surface antigen carriers in neonates who received a complete vaccination course. Furthermore vaccination courses with higher vaccine dosages give high PEs, without concomitant HBIG administration at birth, provided that the first vaccine dose is given at birth and that the second dose follows within 2 months. © 1994 Wiley-Liss, Inc.     

Efficacy of hepatitis-B immunoglobulin and hepatitis-B vaccine in prevention of the HBsAg carrier state in newborn infants of mothers who are chronic carriers of HBsAg and HBeAg

Combined prophylaxis of perinatal transmission of hepatitis B virus (HBV) with hepatitis-B immunoglobulin (HBIG) and hepatitis-B vaccine was investigated in 40 infants born to HBeAg positive carrier mothers. The efficacy of two combined prophylaxis schedules was compared to 78 similar infants in the control group receiving no treatment, by following the HBV markers at regular intervals up to one year of age. In both schedules, the HBIG and HBV vaccine were given at birth, followed by HBV vaccine given at 30 days and 60 days (group I) or 180 days (group II) of age. The incidence of persistent HBsAg carrier in infants born to HBeAg positive carrier mothers was significantly reduced from 92.6 percent at one year of age in the control group to zero percent (group I) and 11.5 percent (group II) in the treated groups. There was no statistical significant difference in the efficacy of these two combined prophylaxis schedules. HBIG given at birth did not interfere with infant immune response to the hepatitis B vaccine. At twelve months of age, anti-HBs could be detected in 77.8 percent of infants in group I and 89.5 percent in group II with mean titre of 621.4 and 1148.0 in group I and group II respectively. It was concluded that combined prophylaxis with HBIG and hepatitis-B vaccine immediately after birth is the best method for prevention of HBV perinatal transmission from HBeAg positive carrier mothers to their infants.     

Impaired humoral response to vaccines among HIV-exposed uninfected infants

Little is known about the vaccine protective response for infants born from HIV-infected mothers. We evaluated the antibody response to hepatitis B, tetanus, and diphtheria vaccine in vertically HIV-exposed uninfected infants and compared them to those of control infants not exposed to the virus. The quantitative determination of specific neutralizing antibodies against hepatitis B, diphtheria, and tetanus were performed blindly on serum samples. The results showed that 6.7% of the HIV-exposed uninfected individuals were nonresponders to hepatitis B vaccine (anti-HBs titer, <10 mIU/ml), and 64.4% were very good responders (anti-HBs titer, ≥1,000 mIU/ml), whereas only 3.6% of the nonexposed infants were nonresponders (χ(2)=10.93; 1 df). The HIV-exposed uninfected infants showed protective titers for diphtheria and tetanus but lower geometric mean anti-tetanus titers compared to those of the HIV-unexposed infants. Our data point to the necessity of evaluating vaccine immune responses in these children and reinforced that alterations in lymphocyte numbers and functions reported for newborns from HIV-infected mothers interfere with the vaccine response.     

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)