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1.
Perinatal transmission of hepatitis B virus (HBV) from asymptomatic HBsAg carrier mothers to their infants was studied in 78 mother-infant pairs by determination of HBsAg, HBeAg and anti-HBe both in the mothers and in their infants at regular intervals for those children up to the time when they reached at least one year of age. Twenty-five out of the 78 (32.1%) infants born to these mothers were HBsAg-positive 2-6 months after birth and they remained so throughout the observation period of at least one year or more. Perinatal HBV transmission occurred only in infants born to HBsAg carrier mothers who were HBeAg-positive (92.6%) but not in those born to HBsAg carrier mothers who had no detectable HBeAg. This study suggests that preventive measures against HBV transmission during the perinatal period should be taken only for infants born to HBsAg carrier mothers who are HBeAg-positive. In addition, the active immune response to HBV was studied in 75 non-HBsAg carrier infants born to HBsAg carrier mothers by determination of anti-HBs at one year of age or older. Forty-three of these infants were treated with HBIG at birth and 32 infants received no treatment. It was found that infants born to HBsAg carrier mothers who were HBeAg-positive had a better active immune response (84.2% positive for anti-HBs) than infants born to HBsAg carrier mothers who had no detectable HBeAg or anti-HBe (14.3% and 20.4% positive for anti-HBs respectively).  相似文献   

2.
In an attempt to interrupt perinatal transmission of hepatitis B, 92 infants born to HBsAg carrier mothers (49 to HBeAg-positive mothers, 30 to anti-HBe-positive with abnormally elevated ALT levels, and 13 to HBeAg/anti-HBe-negative mothers) received 0.5 ml/kg BW of HBIG at birth and at 1 month of age. Three IM injections of hepatitis B vaccine were given at 3, 4, and 9 months of life. All babies who were given the three doses of vaccine developed an active anti-HBs response: of these, 53 (62.3%) had antibody titers higher than 1,000 mIU/ml, 29 (34.2%) had levels between 100 and 1,000 mIU/ml, and the other three (3.5%) were below 100 mIU/ml. At the end of the 2-year follow-up, these three poor responders became anti-HBs negative, whereas the others still had antibody. All but three babies were protected by HBIG plus vaccine treatment. Two chronic HBV infections occurred within 6 months of life presumably because the babies were already infected when prophylaxis started. The third baby became an HBsAg carrier at 9 months of age in spite of a previous response to the vaccine. Simultaneous presence of HBsAg of y specificity and anti-HBs (anti-a) was still detectable at 24 months of age. The vaccine was well tolerated. Passive plus active immunization is an effective procedure for preventing perinatally transmitted HBV infection.  相似文献   

3.
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.  相似文献   

4.
Hepatitis B virus (HBV) DNA was assayed using the polymerase chain reaction in serum samples of 116 hepatitis B surface antigen (HBsAg) carriers, including 30 positive for hepatitis B e antigen (HBeAg) and 86 negative for HBeAg. In the HBeAg-positive group, all were positive for HBV DNA. In the HBeAg-negative group, 80.2% were positive for HBV DNA (80.0% in the healthy carrier group, 90.0% in the chronic active liver disease group, and 69.2% in patients with cirrhosis). This study indicated that every HBeAg-positive carrier as well as the majority of HBeAg-negative carriers were infectious and, in the latter group, that viral replication is most active in patients with chronic active liver disease.  相似文献   

5.
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。  相似文献   

6.
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.  相似文献   

7.
Maternal hepatitis B e Antigen (HBeAg) positivity poses a risk for hepatitis B virus (HBV) mother-to-child transmission (MTCT). In resource-constrained settings, HBeAg testing is recommended as an alternative to HBV DNA testing to establish antiviral prophylaxis eligibility. Nevertheless, the high prevalence of HBeAg-negative chronic hepatitis B (e-CHB) in many countries should not be overlooked. We studied HBV characteristics and explored the potential MTCT risk among HBeAg-negative/HBsAg-positive expectant mothers in an area prevalent of e-CHB. Among 1348 pregnant mothers screened for HBV infection, 81 (6.0%) were HBsAg-positive. These women were examined for HBeAg, HBV DNA, and cord blood HBV DNA. Sixteen (19.8%) of the HBsAg-positive mothers were HBeAg-positive, whereas 65 (80.2%) were HBeAg-negative, including eight inactive carriers (HBsAg <100 IU/ml, HBV DNA ≤ 2000 IU/ml, and ALT < 40 IU/L). Of the remaining 57 HBeAg-negative mothers, ten revealed HBV Basal Core Promoter or Precore mutations, with three having high viremia (HBV DNA > 200 000 IU/mL), which is associated with a high MTCT risk and therefore qualifies them for antiviral prophylaxis. This pilot study provides a cautionary note to the interpretation of negative HBeAg test results when determining eligibility for MTCT antiviral prophylaxis in situations with limited resources and in regions where e-CHB is prevalent.  相似文献   

8.
Perinatal transmission of hepatitis B virus (HBV) from HBsAg carrier mothers who were HBeAg+, antiHBe+, or negative for both HBe markers, was interrupted using either 4 doses of vaccine, or one dose of hepatitis B immunoglobulin (HBIG) at birth, combined with 4 doses of vaccine. In those infants who received HBIG at birth, the antiHBs titre was significantly higher at 1 and 2 months old, but at 6, 9, and 18 months old, there was no significant difference. Among the infants of carrier mothers who did not display HBeAg (i.e., were antiHBe+, or negative for both HBe markers), a transient subclinical infection would have been expected in around 10% had there been no intervention. No evidence of such infection was detected, and no difference in outcome was found between the two treatment groups. Amongst infants born to HBeAg+ carrier mothers, infection occurred in 1 out of 8 who had received HBIG and vaccine, and in 3 of 8 who had received vaccine only. The difference in outcome was not statistically significant, but the numbers analysed were small. The infections which occurred in spite of prophylaxis may be attributable to in utero infection, poor response to vaccine by the infant, or to the mother having a particularly high HBV-DNA level. HBIG given at birth to infants of HBeAg+ carrier mothers may enhance the protection of infants who are destined to be poor responders to vaccine.  相似文献   

9.
The presence of hepatitis B virus (HBV) DNA in the serum and leukocytes obtained from the peripheral blood of 24 mothers and from the cord blood of their newborns was determined by hybridization procedures. HBV DNA was not detected in the serum and leukocytes of six HBsAg-, HBeAg-negative and two HBsAg-positive, HBeAg-negative mothers and their newborn infants. Among the 16 HBeAg-positive carrier mothers, HBV DNA was found in 13 cases (81%) in the serum and in two cases (12%) in leukocytes. Though the viral DNA was not present in sera, it was detected in two of the 16 cord blood leukocyte samples. In follow-up studies, these two infants did not seroconvert up to 15 months of age and they became carriers with elevated serum alanine aminotransferase levels. The results suggest that HBV may be transmitted vertically and such in utero infection may have resulted in immune tolerance leading to a carrier state.  相似文献   

10.
目的观察乙型肝炎病毒母婴阻断长期效果,探讨HBsAg阳性孕妇生产儿童发生慢性HBV感染的相关影响因素。方法随访和收集于2004--2006年在北京地坛医院出生的HBsAg阳性母亲所生,并在出生时进行200单位乙肝免疫球蛋白(HBIG)注射和经过乙肝疫苗10μg,0、1和6个月的完整免疫接种程序的儿童静脉血,采用Abbott微粒子化学发光法检测其HBsAg、抗-HBs抗体、抗-HBc抗体,分析母婴阻断和乙肝疫苗接种的长期效果及其影响因素。结果收集和调查306名儿童年龄3—6(4.84)岁,其母亲生产时HBeAg阳性198人,HBeAg阴性92人。10(3.27%)名儿童发生慢性HBV感染。除慢性HBV感染者外,其余296名儿童,20.27%抗-HBs〈10mlU/ml;44.26%抗-HBs≥10—100mlU/ml;27.03%抗-HBs≥100~1000mlU/ml和8.45%抗-HBs≥1000mlU/m,抗-HBs保护率为79.73%(236/296)。抗-HBc阳性率为7.43%(22/296)。10例感染儿童的母亲生产时HBeAg均为阳性,HBVDNA均在10。拷贝/ml以上,其中8例超过10^8拷贝/ml。结论在进行乙肝疫苗加HBIG注射的HBV母婴传播阻断措施下,HBV母婴阻断失败和慢性H13V感染发生在HBeAg阳性和高病毒载量产妇所生婴儿,在有效阻断后仍需进行抗HBs监测并加强免疫接种。  相似文献   

11.
The aims of this study were to investigate serum hepatitis B virus (HBV) DNA levels at different clinical stages in patients with chronic HBV infection, and to determine the serum HBV DNA level that discriminated HBeAg-negative chronic hepatitis B(CHB) cases from inactive HBsAg carriers. In all, 222 patients, encompassing 68 HBeAg-positive CHB patients (HBeAg-positive, ALT-elevation), 89 HBeAg-negative CHB patients (HBeAg-negative, ALT-elevation), and 65 inactive HBsAg carriers (HBeAg-negative, ALT-normal), were tested. The ALT levels had been tested more than twice during the previous six months, and the serum HBV DNA levels were quantified by a polymerase chain reaction-based assay. The serum HBV DNA levels of the HBeAg-negative patients were significantly lower than those of the HBeAg-positive patients (median 2.7 x 10(4) vs. 1.6 x 10(8) copies/mL; p=0.000). In addition, the HBV DNA levels of the HBeAg-negative CHB patients were significantly higher than those of the inactive HBsAg carriers (median 2.2 x 10(5) vs. 3.2 x 10(3) copies/ mL; p=0.000). The optimal HBV DNA level for discriminating HBeAg-negative CHB cases from inactive HBsAg carriers was 2.0 x 10(4) copies/mL. The serum HBV DNA levels were lower than the cutoff value in 72.3% (47/65) of the inactive HBsAg carriers, and in 31.5% (28/89) of the HBeAg-negative CHB patients. The serum HBV DNA levels differed significantly between these two groups. However, the levels in the two groups overlapped extensively, preventing the definition of a differentiation cut-off value.  相似文献   

12.
Perinatal transmission of hepatitis B virus in high-incidence countries   总被引:11,自引:0,他引:11  
Hepatitis B is a serious public health problem throughout the world. Hepatitis B virus (HBV) induces acute hepatitis with a case-fatality rate of about 1%. Even more important, 5-10% of patients infected with HBV become chronic carries and about 25% of these will die due to cirrhosis and hepatocellular carcinoma. The reservoir of HBV chronic carriers in the world is estimated at more than 200 million people and 80% of them reside in Asia and the western Pacific. In high-incidence areas, such as south-east Asia, perinatal transmission of HBV from carrier mothers to newborns appears to be the most important factor for the high prevalence of HBV infection and 70-90% of infants born to HBsAg/HBeAg-positive mothers become chronic carriers. Three possibilities of transmission of HBV from carrier mothers to newborns are suggested: (a) transplacental transmission in utero - it was estimated that such transmission occurred in 5-15% of newborns; (b) transmission during delivery, which is considered the main mode of perinatal transmission; (c) postnatal transmission from mother to newborn, which is not common. HBeAg is the main maternal factor in determining whether infection of newborns will occur; the expression of this antigen seems to be determined genetically. Recently it has shown that immunoprophylaxis is highly effective in preventing the development of the carrier state in infants born to HBsAg/HBeAg-positive mothers. Only 5-10% of high-risk infants are not protected by vaccination. If it becomes possible to immunize the entire world population including all babies born to carrier mothers at birth, and if our knowledge of the mechanisms of perinatal transmission of HBV is accurate, the carriers and acute cases of HB ought to disappear in two to three generations.  相似文献   

13.
The level of hepatitis B virus (HBV) DNA in serum reflects the replicative activity of HBV. To compare serum HBV DNA levels in different states of hepatitis B, 47 sera of patients with HBeAg-positive chronic hepatitis B, 4 sera of patients with HBeAg-negative chronic hepatitis B, 40 samples of patients after HBeAg seroconversion during alpha interferon treatment, 57 sera of inactive HBsAg carriers, and 42 sera of patients who had recovered from chronic hepatitis B more than 12 months prior to blood collection were checked for the presence of HBV DNA with the Amplicor HBV Monitor Test. In patients with HBeAg-positive chronic hepatitis B, the median of serum HBV DNA levels (8.3 x 10(8) copies/ml) was significantly higher than that for patients after HBeAg seroconversion (6.2 x 10(3) copies/ml) and than that for inactive HBsAg carriers (5.6 x 10(3) copies/ml). None of the patients who had recovered from hepatitis B had detectable HBV DNA in serum. Quantitative PCR proved to be a valuable tool for identification of different states of HBV infection. This technique was found to be a good method for determination of serum HBV DNA levels both for patients with HBeAg seroconversion and for inactive carriers who showed low viremia not detectable by conventional hybridization assays.  相似文献   

14.
Over 90% of infants infected with hepatitis B virus (HBV) caused by mother-to-infant transmission will evolve to carrier status, and this cannot be prevented until widespread administration of the HB vaccine and hepatitis B immune globulin (HBIG) is implemented. This prospective study of 214 infants born to HBsAg-positive mothers was carried out to determine if either perinatal or intrauterine HBV transmission could be effectively prevented with HBIG and the HB vaccine. Peripheral blood was collected from mothers and from newborns before they received HBIG and the HB vaccine, as well as at 0, 1, 7, 24, and 36 months after birth. Infants born with an ratio of signal to noise(S/N) value of >5 for HBsAg (ABBOTT Diagnostic Kit) were defined as mother-to-infant transmission cases, those with an S/N between 5 and 50 were classified as perinatal transmission cases, and those with an S/N >50 were considered intrauterine transmission cases. Mother-to-infant transmission occurred in approximately 4.7% (10/214) of the infants; the perinatal transmission and intrauterine transmission rates were 3.7% (8/214) and 0.9% (2/214), respectively. The risk of mother-to-infant transmission increased along with maternal HBeAg or HBVDNA levels. After 36 months of follow-up, all perinatal cases became HBsAg-negative, whereas all intrauterine transmission cases evolved into carrier status. These results indicate that infants infected via intrauterine transmission cannot be effectively protected by HBIG and HB vaccine.  相似文献   

15.
One hundred eleven newborn infants born of Spanish hepatitis B surface antigen (HBsAg) carrier mothers were consecutively assigned to one of three treatment groups. Group A was treated with three or four doses of hepatitis B immune globulin (HBIG) in one of three different schedules. Group B received one dose of hepatitis B vaccine (Hevac-B, Pasteur) at birth and at 1, 2 and 12 months. Group C was treated with the same vaccination schedule as group B and in addition received a single dose of HBIG at birth. Comparisons were made in the 85 babies who had strictly completed the immunization schedule and had been followed for at least 12 months. The three immunization protocols were equally effective, since none of the children became a chronic HBsAg carrier or developed acute symptomatic infection. There were five transient and subclinical infections among children who received only HBIG (group A), one transient infection in group B, and one in group C. There seems to be some correlation between anti-HBs levels and degree of protection, since all transient infections in group A occurred in the subgroups who did not maintain protective antibodies during the first 6 months. Although the percentage of responders in the two vaccinated groups did not differ significantly, children who received only vaccine reached higher antibody levels than those who also received HBIG. Our results suggest that any immunization schedule able to maintain anti-HBs levels during the first 6 months of life would be useful to prevent mother-to-infant transmission of the hepatitis B virus in areas where most of the carrier women are expected to be anti-HBe positive and hence relatively less infectious.  相似文献   

16.
BackgroundInfants born to chronic hepatitis B virus (HBV) infected mothers may be infected in spite of receiving passive-active immunoprophylaxis.ObjectivesThe purpose of this study was to assess the outcome of infants born to women actively infected by HBV.Study designFrom April 2004 to September 2009, infants born to women actively infected by HBV received hepatitis B immune globulin (HBIG) and the first dose of hepatitis B vaccine at birth. The second and third doses of HBV vaccine were administered at 1 and 6 months of age. Post-vaccination tests to detect HBsAg and anti-HBs were assessed between 12 and 15 months of age. Those who had anti-HBs titers < 10 mIU/ml received the second series of HBV vaccine.ResultsThirty-four and 201 infants were born to HBeAg-seropositive and anti-HBe-seropositive mothers, respectively. HBsAg was detected in 6 (17.6%) infants born to HBeAg-seropositive mothers and in 3 (1.5%) to anti-HBe-seropositive mothers (p = 0.0001). Anti-HBs ≥ 10 mIU/ml were achieved in 26 (76.5%) and 178 (88.6%) infants of HBeAg-seropositive and anti-HBe-seropositive mothers, respectively (p > 0.05). Twenty-two (9.4%) infants were non-responders and 11(50%) of them responded to the second series of HBV vaccine.ConclusionsThe results show that infants of HBeAg-seropositive mothers have higher risk of developing of HBV infection. Some HBsAg-seronegative infants may not respond to passive-active immunoprophylaxis and may remain at risk of HBV infection.  相似文献   

17.
BackgroundHBsAg quantitation may be useful for managing patients with hepatitis B virus (HBV) infection.ObjectivesWe explored the clinical implications of HBsAg quantitation for patients with HBsAg levels >250 IU/ml (Abbott Diagnostics).Study designTwo hundred and thirty-three HBV-infected patients comprising 29 immune tolerance cases, 49 treatment-naïve HBeAg-positive chronic hepatitis B (CHB) cases, 91 inactive HBV carrier cases, and 64 treatment-naïve HBeAg-negative CHB cases were analyzed. HBsAg was quantified by the Architect HBsAg assay (Abbott Diagnostics) after a 1:500 automated dilution.Results and conclusionsHBsAg (log 10 IU/ml) was established for immune tolerance (4.50 ± 0.43), HBeAg-positive CHB (4.17 ± 0.66), inactive HBV carrier (3.32 ± 0.44), and HBeAg-negative CHB (3.23 ± 0.40); (p = 4.92 × 10−35). No significant difference was observed between inactive HBV carrier and HBeAg-negative CHB (p = 0.247). The proportions of HBsAg <2000 IU/ml for inactive HBV carrier and HBeAg-negative CHB were 51.6% and 59.3%, respectively (p = 0.341). Positive correlations between HBsAg and HBV DNA were observed for immune tolerance (p = 1.23 × 10−4) and HBeAg-positive CHB (p = 0.003), but not for HBeAg-negative CHB (p = 0.432). A negative correlation between HBsAg and age was observed for immune tolerance (p = 0.030), HBeAg-positive CHB (p = 0.016), and inactive HBV carrier (p = 0.001), but not in HBeAg-negative CHB (p = 0.249). No significant differences between HBsAg and ALT for HBeAg-positive (p = 0.338) or HBeAg-negative CHB (p = 0.564) were observed. For patients with HBsAg quantitation >250 IU/ml, HBsAg may reflect HBV DNA replication for HBeAg-positive cases. HBsAg is not a suitable marker for evaluating hepatitis activity and distinguishing between cases of HBeAg-negative CHB and inactive HBV carrier state.  相似文献   

18.
ObjectiveTo investigate the long-term incidence and predictors for hepatitis B surface antigen (HBsAg) loss after nucleoside analogue therapy.MethodsThe study included 411 noncirrhotic chronic hepatitis B patients (148 hepatitis B e antigen (HBeAg)-positive and 263 HBeAg-negative patients) who were treated with lamivudine (n = 110) or entecavir (n = 301) with posttreatment follow-up of at least 12 months.ResultsIn HBeAg-positive patients, the 8-year cumulative rates of virologic relapse, clinical relapse and HBsAg loss were 55.6%, 47.7% and 19.6%, respectively. In HBeAg-negative patients, the rates were 69.3%, 58.9% and 33.1%, respectively. Cox regression analysis showed that hepatitis B virus genotype C and lower end-of-treatment HBsAg levels were independent predictors of HBsAg loss in HBeAg-positive and -negative patients. The 5-year HBsAg loss rate was 47.3% in HBeAg-positive patients with end-of-treatment HBsAg levels <300 IU/mL, while the 8-year HBsAg loss rate was 69.3% in HBeAg-negative patients with end-of-treatment HBsAg levels <200 IU/mL. Five patients experienced hepatitis flares with decompensation after stopping nucleoside analogue therapy, and one died after retreatment. Of the 48 patients who developed off-therapy HBsAg loss, two developed hepatocellular carcinoma.ConclusionsThe rate of HBsAg loss was relatively high and the rate of hepatic events was low in noncirrhotic patients who discontinued nucleoside analogue therapy.  相似文献   

19.
To provide background for a hepatitis B vaccine efficacy trial, sera were collected from 0- to 4-year-old Liberian infants and their mothers, on two occasions an average of 14.75 months apart, and tested for serological markers of hepatitis B virus infection. The prevalence of the hepatitis B surface antigen (HBsAg) was 2.9% in the 0- to 6-month age group and 23% in infants 3 to 4 years of age. HBsAg persisted for the 14.75-month average follow-up period in 80.8% of the infants tested. The annual incidence of development of HBsAg was 18.9% for infants less than 1 year of age and 13.6% in infants 3 to 4 years of age. Infants born to HBsAg carrier mothers had significantly higher age-specific prevalence and incidence of hepatitis B virus infection. However, it was estimated that only a minor proportion of hepatitis B infections in Liberia are derived by vertical transmission from carrier mothers.  相似文献   

20.
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.  相似文献   

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