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1.
From October 1982 to May 1983, newborn infants of 79 hepatitis B surface antigen (HBsAg)-positive women were enrolled in a study of the efficacy of hepatitis B immune globulin (HBIG) in the prophylaxis of perinatal transmission of hepatitis B virus (HBV) infection. HBIG 0.5 ml or 0.25 ml was given to the newborn within 15 minutes of birth and at 3 and 6 months. The mother-infant pairs were followed-up every 3 months for at least 9 months. Similar observations of untreated infants were used for comparison. Among infants of hepatitis B e antigen (HBeAg)-positive carrier mothers, the HBsAg carrier rates at 3 months were similar in the 0.5-ml and 0.25-ml HBIG dose groups. At 12 months the difference--17.7% of 17, 40% of 15--did not reach statistical significance, but the differences between these rates and that of the untreated control-85.7% of 35--did. Among infants of HBeAg-negative carrier mothers, HBV infection rates in both dose groups were similar to those of untreated infants. In the treated groups at 12 months about 45% of infants of HBeAg-positive mothers and 90% of infants of HBeAg-negative mothers were still negative for HBsAg and anti-HBs. Vaccination to induce active antibody is necessary to prevent postnatal infection and chronic carriage of HBV. To reduce the cost of combined passive and active hepatitis B immunoprophylaxis in children born to HBeAg-positive carrier mothers, 0.25 ml of HBIG could be used instead of the usually recommended 0.5 ml.  相似文献   

2.
A nation-wide hepatitis B virus (HBV) immunization program of all newborn babies was launched in Mongolia in 1991. However, the continuation of clinical icteric viral hepatitis infections in children led to the investigation to determine whether HBV breakthrough infections were occurring and if any were due to hepatitis B surface antigen (HBsAg) mutants. Hepatitis A virus (HAV) infections accounted for most of these cases with 3% of the jaundiced children shown to have acute hepatitis B. Hepatitis B vaccine protection was 93% against HBV infection and 97% against HBV carriage. A G145A "escape mutant" was found in one HBV carrier child only. Anti-HBs levels, however, were low with 85% having titers less than 100 IU/L, 46% of whom had levels less than 10 IU/L. The results from this study demonstrate that the HBV immunization program in Mongolia provides an effective level of protection. However, continued surveillance of breakthrough infections and close monitoring of "vaccine escape" mutants is required.  相似文献   

3.
Taiwan is an endemic area of hepatitis B virus (HBV) infection. A nationwide mass vaccination program to prevent HBV infection was started in 1985. Perinatal and horizontal transmission of HBV decreased substantially after the launching of this program. However, the influence of this program on children born before 1985 has not been studied. From 1991 to 1999, annual surveys of hepatitis B virus surface antigen (HBsAg) and antibody (anti-HBs) were carried out in freshmen at two high schools in Hualien, Taiwan. The average age was 16 years old. Although these students were born 2-10 years after the start of the national HBV vaccination program, there is a significant trend of decreasing HBsAg carrier rate (from 21.0% to 10.5% in males and 14.3% to 4.7% in females) and increasing anti-HBs rate (from 56.6% to 67.8% in males and 70.3% to 75.9% in females) over the 9 years. With yearly comparison, the carrier rate of HBsAg started to show significant decrease since 1994, while the anti-HBs began to rise significantly after 1996, especially in male students. The HBsAg carrier rate in male students was significantly higher, while the anti-HBs rate was significantly lower, than that in female students in most of the years. It is concluded that the effect of HBV vaccination also reduced horizontal transmission of HBV to children born up to 7 years before the start of the program.  相似文献   

4.
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   

5.
A nationwide hepatitis B vaccination program was launched in Taiwan in 1984. To study the impact of this ongoing program on hepatitis B virus (HBV) infection, a follow-up seroepidemiologic study was carried out in 1989 in a Taipei district where pre-vaccination seroepidemiology had been studied. HBV markers were studied in 1134 apparently healthy children (619 boys and 515 girls) under 13 years of age between March and July 1989. The prevalence of hepatitis B surface antigen (HBsAg) in children under 5 years of age decreased from 9.3% in 1984 to approximately 2% in 1989. A significant decrease in HBsAg prevalence and hepatitis B core antibody in 5- to 8-year-old children who were not immunized against HBV showed that horizontal infection among the older children had also decreased. Thus, this program not only protected vaccinated subjects; the reduction in numbers of highly infectious young HBV carriers also contributed to a lower prevalence of hepatitis B infection and carrier rates in some older children. This study demonstrates that hepatitis B vaccination is effective in protecting the majority of children in hyperendemic areas from HBV infection and from becoming chronic carriers.  相似文献   

6.
The implementation of the Expanded Program of Immunization (EPI) in 1989 has dramatic impact on hepatitis B virus (HBV) infection in school children in Malaysia. A cross-sectional seroprevalence study of HBV infection in 190,077 school children aged 7–12 years from 1997 to 2003 showed a steady decline of HBV surfacce antigen (HBsAg) prevalence rate from 2.5% for children born in 1985 to 0.4% among school children born in 1996. The overall prevalence of HBsAg was 0.6%, 0.7% in males and 0.6% in females. Over 92.7% of school children had been vaccinated with HBV vaccine, in which 93.7% were vaccinated under the EPI and 6.3% on voluntary basis. The school children vaccinated under EPI had a 0.4% HBsAg carrier rate, which was significantly lower than school children vaccinated on a voluntary basis (HBsAg carrier rate 1.3%) and non-vaccinated school children (HBsAg carrier rate 2.7%), suggesting that HBV vaccination of infants was the most effective measure in preventing vertical transmission of HBV in the hyperendemic region.  相似文献   

7.
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   

8.
The sera of 722 children and adolescents without overt liver disease were tested for hepatitis B surface antigen (HBsAg), antiHBs and anti-hepatitis B core anti-HBc; 658 of the sera were also tested for anti-hepatitis A virus anti-HAV. Except for the "passive" antibody peak observed in babies, the anti-HAV age-specific prevalence was negligible until the age of 3; it then increased, reaching 35% by the age of 15. Serological evidence of HBV was present in 16% of the subjects: this prevalence was almost constant at all ages. The HBsAg carrier rate was highest in children under 5 years of age (7.6%) and decreased with age. However, only one HBsAg carrier was under 1 year of age. Anti-HBs age-specific prevalence increased progressively from 2.7% to 11.4%. Anti-HBc alone was present in 4.1% of the subjects. No significant sex differences were found in the prevalence of HBV serum markers or in the HBsAg carrier rate. Neither HAV nor HBV infection was significantly influenced by place of residence or socioeconomic status. It is concluded that in this area both HAV and HBV are endemic, but while HAV is mainly acquired at school, most of the HBV infections occur within the household. The results suggest that not only perinatal transmission, but also intrafamilial horizontal infection, plays a role in HBV spread among infants.  相似文献   

9.
Hepatitis B virus (HBV) markers were studied by radioimmunoassays in serum samples of 1,200 (647 male, 553 female) apparently healthy children under 15 years of age in Taipei between June and October 1984. The prevalence rate of hepatitis B surface antigen (HBsAg) was 5.1% in infancy, increased to 10.7% between 1 and 2 years of age, and then remained constant at about 10% thereafter. The prevalence rate of surface antibody (anti-HBs), core antibody (anti-HBc), and seropositivity (at least one marker of hepatitis B detectable) were 39.0, 30.5, and 52.5%, respectively, in infancy, then decreased to 10.7, 14.3, and 17.9%, respectively, between 1 and 2 years of age. Thereafter, the antibody prevalence increased in parallel with age. By the age of 13-14 years, nearly half of the children were infected by HBV. The results suggested that in our children, most HBsAg carriers resulted from infections before 3 years of age, and HBV infections after 3 years of age infrequently resulted in a carrier state. One hundred (83.3%) of the 120 HBsAg-positive children had hepatitis B e antigen (HBeAg), indicating high prevalence in young asymptomatic HBsAg carriers. The prevalence rate of HBeAg tended to decrease with age and a reversed trend was observed with anti-HBe. Our study, just before our government extends mass hepatitis B vaccination program from newborns to children, provides background seroepidemiologic data of HBV infections in the healthy children in Taiwan.  相似文献   

10.
To determine whether transmission of hepatitis B virus occurs among mentally retarded patients in six institutions, from 1986 to 1988, 373 patients (males 203, females 170, 18-53 years of age, mean age 29.9) were tested for hepatitis B markers. Seventy five of them had Down's syndrome. Overall prevalences were 9.1% for hepatitis B surface antigen (HBsAg), 39.7% for antibody to HBsAg (anti-HBs) and 48.0% for antibody to hepatitis B core antigen (anti-HBc). Prevalence of HBsAg was significantly higher in patients with Down's syndrome than in other mentally retarded patients. Five patients (three males and two females) in four institutions were infected with hepatitis B virus during the two years of observation. Four of these five patients were the other mentally retarded and became both anti-HBs and anti-HBc positive. The remaining one, who was 29 years old and Down's syndrome, became an HBsAg carrier. These observations indicate that hepatitis B virus transmission frequently occurs among mentally retarded patients in institutions and therefore vaccination of susceptible institutionalized patients is necessary. Vaccination to patients with Down's syndrome is particularly warranted, because they are uniquely predisposed to develop chronic hepatitis B infection following exposure.  相似文献   

11.
Amongst adults exposed to the hepatitis B virus (HBV), the infection pursues a fulminant course more frequently in females, while conversely a chronic carrier state is more frequent in males. Because of these differences in sex ratio, we investigated the relationship between the outcome of HBV infection and serum concentrations of sex hormone-binding globulin (SHBG), a circulating glycoprotein that exerts an important influence on the balance of free sex hormones. SHBG levels were significantly elevated in females with fulminant HBV infection compared to females with either uncomplicated acute or chronic HBV infection (P less than .05 and P less than .001, respectively). That this was not a nonspecific effect of fulminant hepatitis was confirmed by the significantly higher levels in this group than in age-matched females with fulminant hepatitis unrelated to HBV (P less than .05). In contrast, four of 15 female HBsAg carriers had SHBG values in the male range, and these included three of four patients who had acquired HBV as adults. SHBG levels were normal in all male groups. These results suggested that for adults the hormonal environment may be important in determining the course of HBV infection.  相似文献   

12.
This study aimed to verify whether rs4986790 A?>?G single nucleotide polymorphism of toll like receptor 4 (TLR-4) associates with a more severe course of hepatitis B virus (HBV) chronic infection. A cross-sectional study enrolled 191 Caucasian HBV-positive patients: 28 HBsAg?+?inactive carriers, 121 chronic hepatitis B, 42 HBsAg?+?transplant candidates. A longitudinal study included 94 patients followed-up for a median time of 19.3 years. TLR-4 rs4986790 A/A genotype was carried less frequently in male HBsAg?+?inactive carriers than in males with HBsAg?+?active chronic infection (12/17 Vs 109/121, p?=?0.022). At stepwise logistic regression analysis, the carriage of TLR-4 rs4986790 A/A genotype was found to be and independent predictor of liver fibrosis (O.R. 14.8, p?=?0.019). In conclusion, in HBV-positive Caucasian patients, the A/A genotype of the rs4986790 polymorphism may influence a worse outcome of chronic HBV infection, mainly through a synergistic interaction with male gender.  相似文献   

13.
Sera from 576 healthy adults were tested for the hepatitis B surface antigen (HBsAg) and antibody (anti-HBs) to evaluate the role of routine dental care as a factor in the spread of hepatitis B virus (HBV) infection. Serological evidence of prior HBV infection, manifested by acquisition of anti-HBs, was detected in 97 (16.8%) individuals, and 6 (1.0%) were identified to be asymptomatic HBsAg carriers. The anticipated correlations of HBsAg and anti-HBs with age, country of birth, and socioeconomic status were observed in the study population. However, prevalences of both HBsAg and anti-HBs were inversely related to the lifetime total of dental care visits. These findings indicated that, in a region in which the HBsAg carrier state and hepatitis B are prevalent, routine dental care is not identified as an important factor in the spread of HBV infection. While the results do not exclude the obvious possibility that cross-infections with HBV may occur during dental care in specific situations, they indicate that this mode of infection is exceptional.  相似文献   

14.
Three doses of inactivated hepatitis B vaccine were given at 1-month intervals to 31 hepatitis B surface antigen (HBsAg)-positive Senegalese children aged between 3 and 24 months. A control group of 18 HBsAg-positive Senegalese children received diphtheria-tetanus-polio vaccine. Immunization of HBsAg-positive infants with hepatitis B vaccine was safe but inefficient. After a 12-month follow-up, the prevalence of HBsAg chronic carriers was not significantly reduced in the hepatitis B vaccine group as compared with the control group: 48.4 and 66.7%, respectively. The presence of hepatitis B antigen was found to be a major risk factor for HBsAg-positive children to develop a chronic carrier state. The risk of developing an HBsAg chronic carrier state was also related to advancing age at time of enrollment in the study.  相似文献   

15.
The magnitude and significance of perinatal transmission of hepatitis B virus (HBV) were assessed in infants of 8,575 women, of whom 3.7% were seropositive for HBV surface antigen (HBsAg). The e antigen of HBV (HBeAg) was found in 7.8% of these carriers, the antibody to HBeAg (anti-HBe) was found in 30.1% of them, and HBsAg alone was found in 62.1% of them. The estimated incidence of HBsAg positivity by 6 months of age in infants of carrier women was significantly (P less than .001) higher than in controls (18.6% vs 3.0%). Transmission was most frequent (87.5%) if the carrier mother was HBeAg positive and was much less so if she was positive for anti-HBe (17.5%) or for HBsAg alone (9.6%). Toward the end of infancy incidence of HBsAg positivity among offspring of carriers and among controls was not different. Most infants positive for HBsAg and HBeAg continued with the infection beyond 6 months of age. It is estimated that about one-third of the adult asymptomatic HBV carriers in India evolve directly from perinatal infection, while the majority become infected during childhood or early adulthood.  相似文献   

16.
Perinatal transmission of and infection with hepatitis B (HBV) in early childhood are observed in a small proportion of the offspring of hepatitis B surface antigen (HBsAg)-positive mothers who are vaccinated against HBV immediately after giving birth. The children may be infected by wild-type HBV or by variants with amino acid substitutions in the "a" determinant of HBsAg, particularly at position 145 and, rarely, at positions 120, 126, 129, 131, 141, and 144. Four hundred and forty-six newborn infants of HBsAg-positive mothers in the northeastern part of the Czech Republic received combined active and passive immunisation against HBV. Only one child became an HBsAg carrier. This followed a mild, acute HBV illness in the beginning of the second year of his life. HBV DNA encoding the "a" determinant and surrounding region of HBsAg was sequenced after amplification from the plasma of the child and his mother. The child was infected with variants of HBsAg with substitutions at residues 137 and 139. The virus of the mother had changes at residues 120 and 121. HBV from both child and mother had an unusual substitution at residue 118 and seemed to be of the ayw subdeterminant.  相似文献   

17.
To study the usefulness of IgM hepatitis B core antibody (anti-HBc IgM) for detecting hepatitis B virus infections in infants of hepatitis B surface antigen (HBsAg) carrier mothers, serial serum samples from 86 infants of carrier mothers were tested for anti-HBc IgM with a highly specific enzyme immunoassay. Asymptomatic hepatitis B infection occurred frequently in infants under 12 mo of age. Anti-HBc IgM never became positive in 25 infants infected under 9 mo old. It was positive in only 1 of 6 infected at 9 mo and 4 of 13 infected at 12 mo of age. The IgM antibody lasted for less than 6 mo. Although the infection was delayed in 28 infants receiving hepatitis B immune globulin, the poor anti-HBc IgM response did not seem to be due to the immune prophylaxis. Our study clearly indicates the limitation of anti-HBc IgM for detecting acute hepatitis B infection in infants born to HBsAg carrier mothers.  相似文献   

18.
Approximately 15 to 20% of the general population in Taiwan are chronic hepatitis B surface antigen (HBsAg) carriers. However, the incidence of hepatitis D virus (HDV) infection is low (5-8%) in patients with HBsAg-positive chronic liver diseases in this area. To evaluate the prevalence of hepatitis B virus (HBV) and HDV infection among drug abusers in Taiwan, serum samples were collected from 152 drug abusers at the Taipei Municipal Anti-Narcotic Institute and test for HBV and HDV markers. Of these, 24 (15.8%) were HBsAg positive, and only 15 (9.9%) were seronegative for all HBV markers. Of the 115 intravenous drug abusers, serum antibody to hepatitis D antigen (anti-HD) was positive in 78.9% of 19 persons who were HBsAg positive, and in 7.5% of 80 persons who were positive for antibody to HBsAg (anti-HBs). Anti-HD was not detected in the sera from all 37 nonintravenous drug abusers regardless of the status of their HBV markers. Also, none of 63 asymptomatic HBsAg carrier pregnant women or 23 patients with acute type B viral hepatitis had measurable anti-HD in their sera. Thus, the high frequency of HDV detected among Chinese HBsAg carrier intravenous drug abusers in Taiwan is similar to that reported in Western countries.  相似文献   

19.
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   

20.
Summary The histopathology of the liver and the detectability of intrahepatic hepatitis B virus (HBV) markers were studied in 34 autopsy cases in elderly patients (mean age 73.9 years, range 60–91 years) who had had a history of positive HBV surface antigenaemia prior to death. Seven of 14 persistent HBV carrier cases (group A) in which long-lasting HBV surface antigen (HBsAg) carriage in the sera had been confirmed by sequential assays, and 5 out of 15 HBV-infected people (group C, single assay) showed significant primary liver damages including chronic hepatitis, toxic hepatitis, liver cirrhosis and hepatocellular carcinoma. In 5 cases (group B), one of which was type B liver cirrhosis, HBsAg became negative and HBsAb appeared during the follow-up period (up to 33 months). Among confirmed HBV carriers, HBsAg and HBV core antigen were most frequently found in the liver of cirrhotic cases with and without hepatocellular carcinoma (5 of 6), whereas these were rarely detected in those with nonspecific changes or slight hepatitic activity (1 of 7). All 5 cases in group B were negative for histological HBV-related antigens and the findings in group C were variously interpreted. Post-mortem cases of the aged HBV carriers who survived their mean life expectancy represent an important population in which to study the natural history of HBV carriers.  相似文献   

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