国产重组酵母乙型肝炎疫苗阻断乙型肝炎母婴传播的研究

目的 探讨乙型肝炎基因工程疫苗阻断HBV母婴传播的免疫保护效果和免疫策略。方法 对HBsAg和HBeAg同时阳性母亲的169例新生儿接种国产重组酵母乙型肝炎疫苗,于免后3、9、12、24、36、48月采血进行血清免疫学追踪观察。结果 22例婴儿1岁前HBsAg阳性,19例（11．24％）成为慢性携带者,免后一年阻断保护率为85．94％。抗－HBs阳性率和抗－HBs滴度均于9－12月龄时达一高峰,24和36月龄时有所下降,免后1－4年抗－HBs阳性率分别为96．43％、91．07％、85．19％和70．00％。结论 国产酵母重组乙型肝炎疫苗对HBV母婴传播具有良好免疫阻断效果。母亲HBsAg和HBeAg双阳性的幼儿在3－4岁时需加强免疫。     

Clinical trial of hepatitis B vaccine in a simplified immunization programme

A study was conducted in the rural areas of Senegal to assess the immunogenic effect of 2 doses of hepatitis B vaccine with a 6-month interval followed by a booster dose after another month and to compare them with those obtained using 2 doses of a vaccine with a 2-month interval or 3 doses at 1-month intervals. The study population of infants received 3 injections of hepatitis B vaccine at 6-month intervals (T0, T6, and T12, respectively), with the 3rd dose as a booster. Other vaccines also were administered to subsets of children: BCG and diphtheria/tetanus/pertussis-polio (DTP-polio) at T0 and DTP-polio at T6 and T12. 664 infants received the 1st dose of hepatitis B vaccine, 409 the 2nd dose, and 177 the 3rd dose. Blood samples were taken at the time of each injection and in the case of 89 infants also 2 months after the last (booster) dose. Only 26.7% of the infants completed the entire series of injections. Only results from infants who were seronegative at T0 are presented, i.e., 281 infants at T6, 116 at T12, and 65 at T14. At T0 the mean age of the seronegative infants was 10.2 months and that of the seropositive infants with anti-HB antibodies was 7.4 months. The mean age of infants who were only anti-HBc-positive was 4.8 months and that of infants who were already HBsAg-positive at T0 was 14.3 months. The results were compared with those reported for 2 other groups of Senegalese infants: 72 seronegative infants who were immunized using a protocol of 2 doses of hepatitis B vaccine with a 2-month interval; and 111 seronegative infants immunized using 3 doses at 1-month intervals. Both groups also received a booster 12 months after the 1st dose. The anti-HBs response was determined 6 months after the T0 dose of hepatitis B vaccine for the 281 infants who were seronegative. 185 of these children (65.8%) exhibited anti-HB antibodies, but the geometric mean titre (GMT) was only 6.1 mlU/ml. The anti-HBs response of the 116 infants who received the 2nd dose of vaccine was determined when the 3rd (booster) injection was given (T12): 104 were positive for anti-HBs (89.7%), and the anti-HBs GMT was 83.7 mlU/ml. Assay of blood samples from 65 infants 2 months after the booster dose indicated that 62 (95.4%) had anti-HBs antibodies, the anti-HBs GMT reaching 348 mlU/ml. The study results establish that infants administered two 5-mcg doses of hepatitis B vaccine with a 6-month interval exhibit a seroconversion rate and antibody levels comparable to those produced using a protocol comprising 2 doses with a 2-month interval or 3 doses at 1-month intervals.     

Immunogenicity and safety in newborns of a new recombinant hepatitis B vaccine containing the S and pre-S2 antigens.

A study to evaluate the safety and immunogenicity of a recombinant hepatitis B vaccine containing the S and pre-S2 antigens (GenHevac B Pasteur) was conducted in healthy newborn infants. All infants received 20 micrograms of vaccine within 24 h of birth and at 1 and 2 months with a booster injection at month 12. The vaccine was administered alone in 19 infants born to low risk mothers, i.e. surface antigen (HBsAg)-negative and antibody to the core antigen (Anti-HBc)-positive mothers. The vaccine was administered in combination with 100 IU hepatitis B immune globulin (HBIg) at birth and 1 month in 18 infants born to high risk mothers, i.e. HBsAg positive mothers. In the group not receiving HBIg, the anti-HBs seroconversion rate at the 10 mIU ml-1 threshold was 50% 1 month after the first injection. In both groups, the anti-HBs seroconversion rates were 100% 1 month after the third injection and greater than 85% 1 month after the second injection. After the booster injection greater than 90% of the infants had an anti-HBs titre greater than 1000 mIU ml-1 which will probably provide them with adequate protection for several years. The kinetics of the anti-pre-S2 response was similar to that of the anti-HBs response and 100% of infants in both groups had seroconverted 1 month after the second injection of the vaccine. The side effects were scarce, all mild and transient.(ABSTRACT TRUNCATED AT 250 WORDS)     

儿童乙型肝炎疫苗加强免疫效果研究

目的　观察新生儿乙肝疫苗免疫后 ,加强免疫接种后的免疫应答的状况和特点。　方法　在乙肝疫苗试点区 ,选择新生儿乙肝血源疫苗免后 9～ 11年的儿童 170名 ,用 5 ug重组酵母乙肝疫苗进行加强免疫。　结果　加强免疫后1年 ,抗 - HBs的 GMT水平迅速升高为原来的 6～ 18倍 ,抗 - HBs阳性率也由免疫前的 6 2 .5 %～ 6 7.5 %上升至 10 0 % ;后随着加强免疫时间的延长 ,抗 - HBs的 GMT水平和阳性率逐渐下降 ,至免后 3年 ,1针加强组抗 - HBs阳性率降至 71.2 % ,2针加强组降至 79.2 % ,而 3针加强组仅降至 92 .5 %。　结论　国产乙肝备源疫苗具有持久的预防保护效果 ,以及良好的免疫回忆反应 ;加强免疫的效果与加强针次和加强免疫前的免疫状况有密切的关系。     

Five-year follow-up of vaccination against hepatitis B virus in newborns vaccinated with a reduced number of doses

The protective efficacy and long-term immunogenicity of a schedule with a reduced number of vaccinations in infants born to mothers positive for hepatitis B surface antigen (HBsAg) has been investigated: 494 infants immunized with a plasma derived hepatitis B vaccine (Hevac B Pasteur) at day 20 after birth and 2 months later were studied. Anti-HBs seroconversion rate was 96% after the second dose, a value similar to that obtained in older children. At 5 years of life anti-HBs at protective levels was still 95.8%. In conclusion, we suggest that this effective and economical reduced vaccination schedule, which before this study was applied to older children, can be used in newborns from HBsAg positive mothers with good protective efficacy shifting the beginning of active immunization from birth to day 20.     

不同月龄婴儿乙肝疫苗免疫效果评价

[目的]探讨婴儿乙肝疫苗免疫的最佳时机。[方法]将孕期检测HBsAg、抗-HBc均为阴性的母亲所产的健康婴儿78例,分为对照组和实验组,分别于出生后24 h内、3月龄时开始乙肝疫苗0,1,6月3针免疫,全程免疫后1、6、12、24个月时以RIA法检测抗-HBs滴度。[结果]3月龄时开始免疫组全程免疫后1、6、12、24个月时抗-HBs滴度均高于出生后24 h内免疫组。[结论]HBsAg、抗-HBc均为阴性的母亲所产的健康婴儿3月龄时开始乙肝疫苗免疫效果较好。     

乙肝免疫球蛋白联合乙肝疫苗阻断HBV母婴传播的相关性研究

目的:探讨乙肝免疫球蛋白(HBIG)联合乙肝疫苗阻断乙肝病毒(HBV)母婴传播失败原因。方法:选择HBsAg阳性、HBeAg阳性、HBV-DNA阳性孕妇218例,检测孕妇分娩前HBVDNA,新生儿(出生24h内且未进行阻断前)、7月龄及1岁时婴儿的HBsAg、抗HBs;所有新生儿出生后24h内在三角肌注射HBIG200IU,同时在大腿前部外侧肌内注射基因工程乙肝疫苗10μg,2周再注射同等剂量的HBIG,1、6月时分别注射同等剂量的乙肝疫苗。结果:孕妇分娩前血清HBVDNA含量>1×106copies/ml组7月龄、1岁时HBsAg阳性率分别为18.12%、19.38%,HBVDNA含量<1×106copies/mi组为7.50%、7.25%(P<0.05)。注射HBIG及乙肝疫苗后,宫内感染组7月龄、1岁时HBsAg阳性率分别为75.00%、74.19%,非宫内感染组为3.76%、4.19%(P<0.01)。结论:宫内感染及孕妇分娩前血清HBVDNA含量高是HBV母婴阻断失败的主要原因。采取综合措施可提高母婴阻断效果。     

Post-vaccination serologic testing of infants born to hepatitis B surface antigen positive mothers in 4 provinces of China

ObjectiveTo evaluate prenatal maternal hepatitis B virus (HBV) screening and post-vaccination hepatitis B surface antigen (HBsAg) and antibody to hepatitis B surface antigen (anti-HBs) status and titers of babies born to HBsAg positive mothers, and to provide evidence for development of standard postvaccination serologic testing (PVST) strategies for babies born to HBsAg positive mothers in China.MethodsIn 2014, we conducted a baseline survey of HBV mother to child transmission (MTCT) interruption strategy implementation and PVST for babies born to HBsAg positive mothers after received 3 doses of hepatitis B vaccine (HepB) in 8 counties in 4 Provinces. Bivariate analysis and multivariable analyses modeled statistically significant predictor variables associated with infant HBsAg, anti-HBs positive, anti-HBs titer.ResultsAmong the 1563 infants born to HBsAg positive mothers, 1025 (65.6%) maternal-infant pairs were enrolled in PVST after receiving 3 doses of HepB. 38 infants tested HBsAg positive for an HBsAg positive rate of 3.7%. Maternal hepatitis B e antigen (HBeAg) status and age of infant were significantly associated with infant HBsAg positivity. A total of 932 infants were anti-HBs positive when tested at 7–24 months of age, yielding an anti-HBs positivity rate of 90.9%. Maternal HBeAg status was the factor associated with infant anti-HBs status. Amount of antigen of HepB and infant’s age were most associated with anti-HBs titers. PVST performed 1–2 months after the 3rd dose of HepB was associated with the highest anti-HBs level and the anti-HBs Geometric Mean Concentration (GMC) decreased as the PVST intervals prolonged.ConclusionsIn China, perinatal HBV transmission is approaching the theoretical minimum possible with the current strategy of HepB coupled with HBIG administration for HBV-exposed newborns. PVST of infants born to an HBsAg positive mother is an essential strategy to ensure full protection for vaccine non-responders and appropriate medical care for those infected.     

乙型肝炎高效价免疫球蛋白联合乙型肝炎疫苗免疫母亲和婴幼儿的随访研究

目的探讨乙型肝炎(乙肝)病毒(HBV)表面抗原(HBsAg)阳性母亲所产婴幼儿经乙肝高效价免疫球蛋白(HBIG)和乙肝疫苗联合免疫后的免疫效果。方法对184例HBsAg阳性母亲所产婴幼儿进行随访调查,于婴幼儿7、24、36月龄应用酶联免疫吸附试验检测血清HBV主要标志物。结果184例婴幼儿出生时HBsAg阳性者7例,HBV宫内感染率为3．80％(7／184)。分娩时HBsAg、HBeAg双阳性母亲所产婴幼儿HBV宫内感染率为11．63％(5／43);而单阳性母亲感染率约为1．42％(2／141)。7月龄随访到125例要幼儿,24、36月龄随访到108例婴幼儿,仅2例出生于双阳性母亲的婴幼儿HBsAg仍持续阳性,其余在7月龄随访时均已阴转,HBV慢性感染率为28．57％。婴幼儿出生时抗-HBs阳性率为7．02％,经HBIG和乙肝疫苗联合免疫,7月龄时抗-HBs阳性率达92％,24月龄降为72．04％。而婴幼儿抗-HBs产生与母亲双阳性无关,与其出生时HBsAg阳性呈显著相关。双阳性39例母亲所产婴幼儿出生时25例HBeAg阳性,随访时除2例HBsAg为阳性的婴幼儿HBeAg仍持续阳性外,余均转阴。随访中未见婴幼儿出现HBsAg或HBeAg阳转。结论HBsAg阳性母亲所产婴幼儿经HBIG和乙肝疫苗联合免疫后免疫效果良好,母亲双阳性可能并不影响婴幼儿联合免疫后抗-HBs的产生。     

326例30个月以下婴幼儿乙肝标志物模式的调查分析

目的:探索新生儿乙肝标志物模式和接种乙肝疫苗后的免疫状态,分析新生儿免疫状态在30个月以内的变化和影响因素。方法:选取326例30个月以内婴幼儿,188例7～30个月完成初次全程免疫接种婴幼儿。采用酶联免疫法对各年龄段婴幼儿乙肝5项指标进行测定。同时对0～1个月新生儿母亲的孕期检查进行回顾性分析。结果:受检婴幼儿的乙肝五项指标中,单纯抗-HBs的阳性率在7～12个月达高峰,为93%,25～30个月时下降至65.3%。抗-HBc阳性所占比例在0～1个月的新生儿中最高,随年龄的增长比例降低。0～1个月的新生儿与母亲乙肝5项模式中各抗体的阳性率比较差异无统计学意义,其中母亲为HBsAg阳性的新生儿,抗-HBc的阳性率为100%。结论:全程接种乙肝疫苗结束后1个月及在25个月后都应及时检测乙肝标志物,提高乙肝疫苗接种失败率及抗-HBs水平衰减的检出,以便及时复种。对于母亲是乙肝病毒携带者的婴幼儿,应在出生时、全程免疫后1个月、25个月时进行乙肝标志物的检查,以检测新生儿阻断的效果及乙肝标志物的动态变化。     

The long-term efficacy of Chinese hamster ovary cell derived hepatitis B vaccine after being used for 14–16 years in Chinese rural communities

ObjectiveTo evaluate the long-term efficacy of Chinese hamster ovary (CHO) cell derived hepatitis B vaccine after being used for 14–16 years in country community in Hebei province in China.MethodA cross-sectional investigation was carried out in 3 of 7 randomly selected rural communities in Zhengding County in 2013. The children who were born between 1997 and 1999 and were vaccinated with three doses of CHO-derived hepatitis B vaccine were eligible to participate in the study. Their sera samples were tested for HBV serological markers. For HBsAg positive children, their historical results were compared, in order to see whether these were new infections.ResultsAmong the 920 participating children, the prevalence of HBsAg, anti-HBs and anti-HBc were 0.65%, 73.15% and 1.20% respectively. The differences between birth-year groups were not significant. When compared with baseline, the vaccine efficacy was 94.2% and the anti-HBs titers of 668 children with sole anti-HBs positivity were 178.8 mIU/ml. By comparing with historical data, no new infection was found in this latest survey. Among 6 mothers of HBsAg positive children, 4 were HBsAg positive, 1 was negative and 1 was unknown.ConclusionThe long-term efficacy of the CHO derived hepatitis vaccine is good and stable for 14–16 years after vaccination. A booster dose seems not necessary. Implementing mother–newborn blocking measures for newborns from HBsAg carrier mothers is urgently needed in the future.     

Low-dose intradermal administration of recombinant hepatitis B vaccine in children: 5-year follow-up study.

Several studies have documented the efficacy of low-dose intradermal administration of hepatitis B vaccine. However, little is known about the duration of protection provided by low-dose intradermal administration of hepatitis B vaccine. This study reports results from a 5-year follow up period of 200 healthy children (100 infants and 100 preschool children) immunized intradermally with 2 microg doses of recombinant hepatitis B vaccine (GenHevac B) at months 0,1, and 6. In the 8th week after the third vaccine dose, 97% of the children developed anti-HBs antibodies higher than or equal to 10 mlU ml(-1), and the antiHBs geometric mean titre (GMT) was 676 mlU ml(-1). In month 18 and year 5, the anti-HBs GMT decreased to approximately one-third (220 mlU ml(-1)) and one-tenth (68 mlU ml(-1)) of the initial levels, respectively. However, 87% of the children had protective levels of anti-HBs (> or =10 mlU ml(-1)) after 5 years. Among 156 children followed for 5 years, none became positive for anti-HBc and/or HbsAg. Seven children who were seronegative after 5 years developed anti-HBs antibodies higher than 1000 mlU ml(-1) after an additional 10 microg intramuscular hepatitis B vaccine. Persistent immunologic memory over periods of 5 years or more is evident, the anamnestic antibody response to a booster dose of vaccine, even in these children who have lost antibody. We conclude that intradermal administration of 2 microg recombinant hepatitis B vaccine provides long-term protection against hepatitis B virus in infants and preschool children.     

广西壮族自治区隆安县乙型肝炎疫苗全程接种后的免疫记忆研究

目的了解接种全程乙型肝炎（乙肝）疫苗后的免疫记忆情况。方法1987-1989年出生时接种乙肝血源疫苗的1201名新生儿,以及1996-1999年出生时接种乙肝酵母重组疫苗的2484名新生儿,于2005年随访时检测乙肝表面抗原（HBsAg）、表面抗体（抗-HBs）和核心抗体（抗- HBc）,结果959名3项乙肝病毒（HBV）标志物均阴性,其中228名接种乙肝血源疫苗,731名接种乙肝酵母重组疫苗,于加强免疫1针乙肝酵母重组疫苗后15 d时检测其抗-HBs。此外,随机选择11名加强免疫后无应答和22名有应答者,应用酶免疫斑点法（ELISPOT）测定白细胞介素-2（IL-2）。有初次免疫后抗-HBs定量检测资料者190名,比较其初次免疫和加强免疫后抗-HBs水平。结果加强免疫后,79．82%接种乙肝血源疫苗者抗-HBs阳转,几何平均滴度（GMT）为325．69 mIU/ml;95．62%接种乙肝酵母重组疫苗者抗-HBs阳转,GMT为745．18 mIU/ml。加强免疫后所产生的抗-HBs水平与初次免疫后抗体滴度有关。加强免疫后抗-HBs阳转者的IL-2阳性率（40．91%）也高于无应答者（P＜0．01）。结论在乙肝疫苗初次免疫后,抗-HBs转阴者中,大部分仍具有免疫记忆,仅少部分在长期随访中丧失免疫记忆。因此,在高流行地区,对丧失免疫记忆者应进行乙肝疫苗加强免疫。     

乙型肝炎基因重组疫苗免疫效果及持久性观察

目的 探讨乙肝基因重组疫苗对新生儿的免疫效果及免疫持久性。方法 随机选择珠海市1999～2003年出生、母亲HBsAg阴性、严格按免疫程序及时全程完成3针基础国产基因重组乙肝疫苗（5ug）的儿童，按免疫后不同的时间段分成6组，采集静脉血分别进行抗-HBs、HBsAg和抗-HBc检测。结果 抗-HBs有效阳性率（≥10mlU／ml）、几何平均滴度（GMT）逐年下降，分别由基础免疫完成后1个月的95，45％和65．36mlU／ml，降至4年后的38．27％和6．56mlU／ml，免疫1年后的下降率最为显著。及时完成3针基础乙肝疫苗免疫后各不同时间段的儿童HBsAg阳性率均不超过1％，抗-HBc阳性率和HBV感染率均小于2％，未见随年限延长而增张的趋势。结论 基因重组乙肝疫苗在新生儿中免疫效果良好，存在较好的免疫持久性和保护效果，在全程免疫后5年内没有必要进行加强。     

重组(酵母)乙型肝炎疫苗免疫后5年随访结果

目的 探讨新生儿接种国产重组(酵母)乙型肝炎(乙肝)疫苗后的免疫效果,并与血源乙肝疫苗效果比较.方法 对1997年出生并接种重组(酵母)乙肝疫苗的新生儿隔年随访一次,采血检测乙肝病毒表面抗原(HBsAg),乙肝病毒表面抗体(抗-HBs)和乙肝病毒核心抗体(抗-HBc),1998年以后对乙肝免疫人群开展急性乙肝发病监测....     

血源乙型肝炎疫苗免疫持久性观察

为了解血源乙型肝炎（乙肝）疫苗的免疫持久性,对澄江县1991～1995年按照0、1、6个月免疫程序完成血源乙肝疫苗接种的人群,按接种后间隔1～5年分组,每组随机抽取100名儿童,采末梢血,共得517份免疫者的血清样品．用酶联免疫吸附试验（ELISA）检测抗-HBs、HBsAg。结果表明,接种乙肝疫苗2年内抗-HBs阳性率在90％以上,以后随间隔年眼的延长而明显下降,间隔5年降至60％,人群平均保护率达78.57％．     

Significance and anamnestic response in isolated hepatitis B core antibody-positive individuals 18 years after neonatal hepatitis B virus vaccination in Taiwan

Aim

To investigate the significance of isolated hepatitis B core antibody (anti-HBc) and to analyze the response to hepatitis B virus (HBV) booster vaccination in young adults with isolated anti-HBc who had been fully vaccinated with HBV vaccine as infants.

Materials and methods

We screened 1734 new university entrants who had been fully vaccinated against HBV in infancy for the presence of hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and anti-HBc upon university entry. Results positive for isolated anti-HBc were reconfirmed by testing for the presence of HBsAg and anti-HBc once more, and further evaluated for anti-HCV, anti-HIV, and HBV DNA status 6 months later. Students were also offered HBV booster vaccinations at that time. Geometric mean titers (GMT) of anti-HBs after one booster dose of HBV were compared between students with isolated anti-HBc and students with HBV naïve status.

Results

The overall prevalence of isolated anti-HBc in our student cohort was 1.2% (21 of 1734). No evidence of occult HBV infection was observed. A “booster” anamnestic response (anti-HBs titer ≥10 mIU/mL) was noted in 95% (20 of 21) of subjects with isolated anti-HBc. After re-measurement of anti-HBc, 13 (62%) of the 21 subjects with isolated anti-HBc were reclassified as having resolved HBV infection with a loss of anti-HBs. In the remaining 8 subjects (38%), isolated anti-HBc was determined to be false positive. The HBV status of these 8 subjects was HBV naïve due to the waning-off effect of anti-HBs of the neonatal HBV vaccination. There was no significant difference in anamnestic response to a single HBV booster dose of vaccine between students with isolated anti-HBc (n = 13) and those with HBV naïve (n = 323) status (GMT 50.6 vs 47.7 mIU/mL, P = 0.90).

Conclusion

The presence of isolated anti-HBc 18 years after HBV vaccination can be attributed to post-HBV infection with a loss of anti-HBs and to a decline in anti-HBs elicited by vaccine. A single HBV booster dose of vaccine is recommended for subjects with isolated anti-HBc who were fully vaccinated with HBV vaccine as infants. This finding needs to be replicated in further studies with larger cohorts.     

HBsAg阳性母亲的新生儿乙型肝炎疫苗免疫后追踪观察

目的探讨不同方案乙型肝炎疫苗免疫，对母亲ＨＢｓＡｇ阳性新生儿的免疫持久性。方法在２０３名ＨＢｓＡｇ阳性母亲的新生儿出生时，按不同方案和剂量注射乙型肝炎疫苗，免疫后６年内连续进行抗－ＨＢｓ和ＨＢｓＡｇ携带情况的追踪观察。结果６年内抗－ＨＢｓ阳性率一直高于９０％；新生儿免疫后抗－ＨＢｓ在７月龄到１岁形成高峰，在１～２岁期间下降了４８．８２％，２～６岁期间保持相对稳定；８例抗－ＨＢｓ阴转后３～５年仍未被感染；１４例抗－ＨＢｓ阴转１～２年后又产生抗－ＨＢｓ；无一例成为ＨＢｓＡｇ携带者。结论乙型肝炎疫苗免疫后６～１０年可不进行加强免疫。     

Early predictor of the efficacy of immunoprophylaxis against perinatal hepatitis B transmission: analysis of prophylaxis failure.

To research early predictors of the efficacy of the ongoing mass immunoprophylaxis against perinatal hepatitis B virus (HBV) transmission in Taiwan and to analyse the possible causes of immunoprophylaxis failure, 52 hepatitis Be antigen (HBeAg)-positive carrier mothers were recruited for the study. Maternal blood samples were taken at the first and third trimesters and delivery. Umbilical blood was collected and venous blood samples were taken at 4, 7, 11 and 14 months of age. Serum hepatitis B surface antigen (HBsAg) and antibody titres, HBeAg titre and HBV-DNA concentration were analysed. All the umbilical cord blood samples were negative for HBsAg. Among the 52 vaccinated infants, four were poor responders (anti-HBs less than 10 mIU ml-1 before vaccine booster). Another five infants became HBsAg-positive by 4 months of age and remained carriers. All these five carrier mothers were HBV-DNA-positive and three of them had risk factors related to maternal-fetal haemorrhage during pregnancy or delivery. The remaining 43 infants showed protective anti-HBs level (greater than 10 mIU ml-1) by 4 months of age. Three mothers out of these 43 cases also had the same haemorrhage risk factors during pregnancy or delivery, but were HBV-DNA-negative. Therefore, the anti-HBs level at 4 months is a predictor of the success of immunoprophylaxis. It may be helpful to distinguish HBV-DNA-positive carrier mothers among HBeAg-positive ones, to avoid inducing more maternal-fetal haemorrhage in such cases during pregnancy or delivery. Otherwise, additional hepatitis B immune globulin may be indicated in such cases to raise the successful prevention rate.     

邹城市儿童乙型肝炎疫苗接种效果评价

目的评价邹城市新生儿接种乙型肝炎(乙肝)疫苗后的免疫效果。方法自1990年起每年随机抽查50～60名儿童检测接种后的乙肝病毒表面抗体(抗-HBs)阳性率,并调查人群乙肝发病率。1999年采用随机抽样的方法,用酶联免疫吸附试验对人群乙肝病毒表面抗原(HBsAg)携带率进行了调查。结果乙肝疫苗免疫后,儿童保护性抗-HBs的阳性率为90.63%,0～15岁儿童的乙肝发病率明显下降。HBsAg携带率呈下降趋势,儿童尤为明显,从接种前4年平均阳性率13.14%下降到最近4年的0.39%,下降了97.03%。加强免疫和未加强免疫儿童的抗-HBs几何平均滴度(GMT)和保护性抗-HBs的阳性率之间差异均有极显著的统计学意义(χ2=12.35,t=4.51;P均0.01)。结论新生儿实行乙肝疫苗接种可以取得良好的免疫效果,同时加强免疫对维持较高抗-HBs水平阳性率和GMT是有利的。