母源性抗-HBs对新生儿接种乙型肝炎疫苗的远期影响

目的:观察新生儿体内母源性乙型肝炎表面抗体(抗-HBs)对乙型肝炎疫苗接种后抗体应答的远期影响。方法:2006年10月-2007年1月在南京大学医学院附属鼓楼医院产前检查并住院分娩的单胎足月妊娠妇女中,选择抗-HBs阳性孕妇32例,抗-HBs阴性孕妇32例,其新生儿均按0、1、6方案接种重组(酵母)乙型肝炎疫苗,检测两组儿童乙型肝炎疫苗第3针接种后2年血清抗-HBs浓度。结果:新生儿接种乙型肝炎疫苗第3针后2年,母源性抗-HBs阴性组与阳性组儿童抗-HBs阳性率分别为90.6%与87.5%,其抗-HBs几何平均浓度分别为73.48mIU/ml与75.49mIU/ml,两组间抗-HBs阳性率与GMC的差异均无统计学意义(P=1.000,P=0.778);6例母源性抗-HBs>1000mIU/ml儿童中1例抗-HBs转阴(16.7%),而母源性抗-HBs<1000mIU/ml组和母源性抗-HBs组的儿童抗-HBs转阴率分别仅为7.69%和11.1%,但差异无统计学意(P=0.811)。结论:新生儿目前按照0,1,6方案接种乙型肝炎疫苗,能够有效保护其抵抗乙型肝炎病毒的感染;母源性抗-HBs对新生儿接种乙型肝炎疫苗...     

国产放射免疫试剂与Abbott放射免疫试剂检测乙型肝炎病毒感染指征的比较

本文报告了国产乙型肝炎病毒(HBV)RIA和Abbott RIA诊断试剂盒检测质量的比较研究。表明两试剂滴定HBsAg、抗-HBs、抗-HBc阳性血清的敏感性相似,抗-HBs mIU/ml定量检测结果相符。证明国产RIA试剂质量是可靠的。但是,国产试剂S/N值曲线的陡度和标本的阳性检出率较Abbott试剂为高,可能与试剂出厂后周转期短有关。适当提高国产试剂阳性判定标准后,与Abbott试剂的检测符合率可达90％以上。     

中缅树鼩自然感染六种病毒的血清流行病学

中缅树鼩作为一种新型实验动物,在医学生物学上,尤其是病毒学方面的应用受到越来越多的重视.实验动物自身病毒感染会影响动物健康和干扰实验结果,甚至危害实验人员生命安全.所以,实验动物病毒检测一直是动物质量控制的重要部分.中缅树鼩研究迄今缺乏清晰的病毒自然感染资料.为调查中缅树鼩的病毒感染状况,采集野生俘获和人工繁殖的中缅树鼩血清样本272份,全部血清样本通过ELISA方法对乙型肝炎病毒(HBV)表面抗原,丙型肝炎病毒(HCV)总抗体,以及戊型肝炎病毒(HEV)、腺病毒(ADV)、单纯疱疹病毒1型(HSV-1)和2型(HSV-2)的IgG抗体进行了检测.结果表明,ELISA初筛HBV表面抗原有3份阳性样本,但通过乙型肝炎两对半定量检测进一步确认为阴性:抗HCV抗体和抗HEV、ADV、HSV-1 IgO抗体检测均为阴性;抗HSV-2 IgG检测有1份阳性样本.提示仪抗原或抗体血清学指标检测树鼩肝炎结果并不能反应个体携带病毒的状态,应该再进行病毒学指标确认.同时建议中缅树嗣繁殖群应进行HSV-2的筛选,以便杜绝和控制该病毒的感染.     

婴儿围产期感染乙型肝炎病毒后各项血清学指标的动态变化

本文观察了102名新生儿出生后至18月龄的HBV血清学指标的动态变化,婴儿分成乙型肝炎疫苗按种组(63人)和对照组(39人), 观察期间HBsAg始终阴性的70名婴儿,出生后6、12和18月龄的抗-HBc阳性率依次为90％、30％和4.3％;而HBsAg阳转的27名婴儿,18月龄时抗-HBc全都阳性,但仅有6名婴儿在6月龄时测出IgM抗-HBc,疫苗接种组婴儿出生后1、3、6、12和18月龄的抗-HBs阳性率,依次为28.6％、76.2％、77。8％、82.5％和82.5％;对照组婴儿18月龄时抗-HBs阳性率仅为12.8％。     

重庆地区乙肝血清特殊模式患者HBV基因分型及临床自然病程分析

目的了解重庆地区乙肝病毒（HBV）血清学标志物为特殊模式的HBV感染患者病毒基因型的分布情况,分析其临床特征及自然病程。方法从1000例HBV感染者中检测到48例乙肝病毒血清学标志物为特殊模式的患者（HBsAg与抗一HBs同时阳性,HBeAg与抗一HBe同时阳性）。采用巢式聚合酶链式反应（nPCR）对特殊模式患者的HBV进行基因分型,同时对两组特殊模式患者的临床资料和HBV感染的自然史进行分析。结果48例乙肝病毒血清学标志物为特殊模式的HBV感染者中,36例患者HBsAg与抗-HBs同时阳性,12例患者HBeAg与抗-HBe同时阳性。HBeAg＋／抗-HBe＋患者组的年龄较HBsAg＋／抗-HBs＋患者组的小（P〈0．05）。HBsAg＋／抗-HBs＋患者中,3例（8．3％）为B2亚型,12例（33．3％）为c2亚型,21例（58．4％）未分型;HBeAg＋／抗-HBe＋患者中,8例（66．7％）为B2亚型,1例（8．3％）为c2亚型,3例（25．0％）未分型,两组在HBV基因型的分布上差异具有统计学意义（Y2=17．44,P〈0．05）。在HBsAg＋／抗-HBs＋患者中,2例（4．2％）处于免疫清除期,14例（29．2％）处于低复制期,7例（14．6％）处于再活动期。HBeAg＋／抗-HBe＋患者中,5例（10．4％）处于免疫清除期。两组在HBV感染的自然病程中的分布差异具有统计学意义（X2=18．26,P〈0．05）。结论重庆地区乙肝病毒血清学标志物为特殊模式的慢性HBV感染者中,HBeAg与抗-HBe同时阳性的HBV感染者中B2亚型为优势基因型;HBsAg与抗-HBs同时阳性的HBV感染者中,HBV基因型以C2亚型为主。     

不同方法检测血清HBV DNA的比较研究

采用夹心斑点杂交法、PCR-EB定性及Amp-lisensor定量法对HBsAg与抗-HBs同时阳性、HBsAg阳性、抗-HBs阳性和HBsAg与抗-HBs均阴性的乙型肝炎病毒(HBV)感染者检测血清HBV DNA.结果三种方法的阳性率分别为29.1%、47.7%和80.2%;各组HBV DNA含量分别是106.13±1.86、106.08±1.82、104.12±1.40和105.07±1.21(拷贝/ml).结论是Amplisensor法检测HBV DNA具有更高的敏感性;抗-HBs阳性的HBV感染者血清中仍可检出HBV DNA.     

甘肃省1～59岁人群乙型肝炎病毒感染的血清流行病学调查

为了解甘肃省现阶段乙型肝炎病毒感染的现状,分析乙肝病毒感染血清学指标的变化,采用多阶段整群抽样的方法,抽取5个县区1~59岁人群共2200人进行调查。以ELISA方法对血清标本统一检测乙肝病毒表面抗原(HBsAg)、乙肝病毒表面抗体(抗-HBs)、乙肝病毒核心抗体(抗-HBc)。结果显示,甘肃省1~59岁调查人群HBsAg阳性率为3.59%,抗-HBs和抗-HBc阳性率分别为49.45%、16.33%;HBV总感染率为27.50%。比1992年HBV总感染率下降了36.48%,HBsAg阳性率下降了45.94%;1~4岁儿童HBsAg阳性率仅为1.13%,比1992年(5.34%)下降78.84%。甘肃省1~59岁人群乙肝病毒感染率下降,抗-HBs阳性率升高,尤其在1~4岁儿童变化更为明显;甘肃省乙肝感染逐步呈现由中高流行转向低流行区的趋势;乙肝疫苗免疫取得显著效果。     

全人群中HBV易感者接种乙型肝炎血源疫苗后三年的免疫效果观察

在黑龙江省农村10个屯,对全人群进行HBV血清学普查。对查实的1004名易感者,不分年龄性别,都按10μg×3,0、1、6个月程序接种乙型肝炎血源疫苗。免疫后满3年,用放射免疫法(RIA)检测HBV感染指标。结果抗-HBs阳转率(S/N≥10.0)为81.97％,抗-HBs水平(S/N GMT)为111.92;保护率为82.43％,抗-HBc下降38.58％。对加速改变我国乙型肝炎高发区的现状有一定参考意义。     

输血后乙型肝炎的研究

对204例首次受血(1～2单位)的外科手术患者进行了随访,以观察输血后HBV的感染和发病。血源来自224例HBsAg阴性(RPHA法检测)的献血员,受血者于受血前及受血后6～7个月各采血1次,连同献血员献血前的血清,用同一批RIA试剂检测HBsAg、抗-HBs和抗-HBc。发现用RPHA筛选的HBsAg阴性献血员,用RIA检测时,仍有2.2％(5/224)HBsAg阳性。70例HBV易感者中,受血后13例发生HBV感染,其中2例输入HBsAg阳性血液者发生急性肝炎(2.86％),1例为黄疸型乙型肝炎,另一例为NANB肝炎;11例发生HBV感染,其中8例为输入HBV-DNA阳性血液。以上结果表明,RPHA筛选献血员仍不能杜绝输血后肝炎,RIA筛选献血员后不能杜绝亚临床感染。部分HBV感染不能排除医院内感染的可能性。     

HBV感染中抗-(抗-HBs)独特型抗体的研究

1.75％聚乙二醇(MW6000)沉淀血清免疫复合物后,采用ELISA法检测上清中抗独特型抗体〔抗-(抗-HBs)〕。56例急性HBV感染患者血清IgM抗-(抗-HBs),第一周检出率最高(60.00％),1个月后大部分阴性,IgG抗-(抗-HBs)维持时间略长。IgM抗-(抗-HBs)较HBsAg/IgM和IgM抗-HBc消失早,将有利于急性HBV感染的诊断。27例CAH和29例CPH,IgM和IgG抗-(抗-HBs)阳性率约为38～52％,两型间无显著差异(p>0.5)。3例无症状HBsAg携带者和12例HBsAg血清疫苗接受者血清,抗-(抗-HBs)阴性。115例HBV感染者中,IgM抗-(抗-HBs)阳性者HBsAg阳性率(93.62)显著高于IgM抗-(抗-HBs)阴性者(52.31％),p<0.005;反之,HBsAg阳性血清IgM抗-(抗-HBs)阳性率(55.5S％)显著高于HBsAg阴性血清(9.68％),p<0.005;IgM抗-(抗-HBs)阳性和阴性血清的HBVDNA阳性率有显著差异(p<0.025),IgG反应到类似的结果。以上资料表明,抗-(抗-HBs)提示了一些HBV感染患者体内可能存在一种缺陷的反馈机制,导致抗-HBs产生不足而容许更活跃的HBV复制。本文证明了HBV感染患者血清中存在的抗-(抗-HBs)可能是共同决定簇“a”特异性的,还表明抗-HBs人抗-Id反应可能被纯化人血清HBsAg抑制,提示人抗-(抗-HBs)与抗-HBs结合的位点可能在HBsAg与抗-HBs结合位点内或在其附近,这和一些动物抗-(抗-HBs)的研究结果是一致的。     

Prevalence of hepatitis B viral markers in Vietnamese blood donors

Serum samples were assayed using radioimmunoassay in 573 Vietnamese blood donors living in Hano? (North Viet Nam). 66 (11.5%) subjects were HBsAg-positive. Of these 66 HBsAg carriers, 17 (25,8%) were positive for hepatitis B e antigen (HBeAg) and 43 (65.1%) for antibody to HBeAg (anti-HBe). 22 (3.8%) subjects were positive for antibody to hepatitis B core antigen (anti-HBc) alone. 402 (70.2%) subjects were positive for antibody to HBsAg (anti-HBs). This anti-HBs percentage increased with age. Only 83 (14.5%) subjects were negative for all hepatitis B viral (HBV) markers. This no HBV markers percentage decreased with age. The chi 2 test showed a non significant difference for frequencies of HBsAg, anti-HBc alone, anti-HBs but a significant one for frequencies of no HBV markers in men and women.     

High prevalence of occult hepatitis B virus genotype H infection among children with clinical hepatitis in west Mexico

Studies on the prevalence of infection with hepatitis B virus (HBV) among children are scarce in Latin American countries, especially in Mexico. This study was aimed to investigate the prevalence of HBV infection, occult hepatitis B infection (OBI) and HBV genotypes among children with clinical hepatitis. In total, 215 children with clinical hepatitis were evaluated for HBV infection. HBV serological markers and HBV DNA were analysed. OBI diagnosis and HBV genotyping was performed. HBV infection was found in 11.2% of children with clinical hepatitis. Among these HBV DNA positive-infected children, OBI was identified in 87.5% (n = 21/24) of the cases and 12.5% (n = 3/24) were positive for both HBV DNA and hepatitis B surface antigen. OBI was more frequent among children who had not been vaccinated against hepatitis B (p < 0.05) than in those who had been vaccinated. HBV genotype H was prevalent in 71% of the children followed by genotype G (8%) and genotype A (4%). In conclusion, OBI is common among Mexican children with clinical hepatitis and is associated with HBV genotype H. The results show the importance of the molecular diagnosis of HBV infection in Mexican paediatric patients with clinical hepatitis and emphasise the necessity of reinforcing hepatitis B vaccination in children.     

Rare Detection of Occult Hepatitis B Virus Infection in Children of Mothers with Positive Hepatitis B Surface Antigen

The prevalence of occult Hepatitis B virus (HBV) infection in children was considerably varied from 0.1–64% in different reports. In this study we aimed to investigate the prevalence of occult HBV infection among the children born to mothers with positive hepatitis B surface antigen (HBsAg) in Jiangsu, China. Serum samples were collected from 210 children of 207 mothers with positive HBsAg. HBV serological markers were detected by ELISA and HBV DNA was detected by nested PCR. Homology comparison of HBV sequences recovered from the child and mother was used to define the infection. Three children (1.43%) were positive for HBsAg, in whom the HBV pre S and S gene sequence in each child was identical to that in her mother. Of the 207 HBsAg-negative children, nine displayed HBV DNA positive by two nested PCR assays using primers derived from S and C genes. However, the sequence alignment showed that the sequences in each child were considerably different from those in his/her mother. Therefore, the sequences amplified from the children were very likely resultant from the cross-contaminations. Furthermore, the nine children with ‘positive HBV DNA’ were all negative for anti-HBc, and one had anti-HBs 3.42 mIU/ml and eight others had anti-HBs from 72 to >1000 mIU/ml, indicating that the nine children were less likely infected with HBV. Therefore, none of the 207 HBsAg-negative children of HBV-infected mothers was found to have occult HBV infection. We conclude that the prevalence of occult HBV infection in vaccinated children born to HBsAg positive mothers should be extremely low. We recommend that homology comparison of sequences recovered from the child and mother be used to define the occult HBV infection in children born to HBV infected mothers.     

Patterns of hepatitis B virus infection in Brazilian human immunodeficiency virus infected patients: high prevalence of occult infection and low frequency of lamivudine resistant mutations

Hepatitis B virus (HBV) molecular profiles were determined for 44 patients who were infected with human immunodeficiency virus (HIV) type 1 and had antibodies to the hepatitis B core antigen (anti-HBc), with and without other HBV serological markers. In this population, 70% of the patients were under lamivudine treatment as a component of antiretroviral therapy. HBV DNA was detected in 14 (32%) patients. Eight out of 12 (67%) HBsAg positive samples, 3/10 (30%) anti-HBc only samples, and 3/22 (14%) anti-HBs positive samples were HBV DNA positive. HBV DNA loads, measured by real time polymerase chain reaction, were much higher in the HBsAg positive patients (mean, 2.5 x 10(9) copies/ml) than in the negative ones (HBV occult infection; mean, 2.7 x 10(5) copies/ml). Nine out of the 14 HBV DNA positive patients were under lamivudine treatment. Lamivudine resistant mutations in the polymerase gene were detected in only three patients, all of them belonging to the subgroup of five HBsAg positive, HBV DNA positive patients. A low mean HBV load (2.7 x 10(5) copies/ml) and an absence of lamivudine resistant mutations were observed among the cases of HBV occult infection.     

Investigation of Occult Hepatitis B Virus Infection in Anti-HBc Positive Patients from a Liver Clinic

Occult hepatitis B infection (OBI) is manifested by presence of very low levels (<200IU/mL) of Hepatitis B viral DNA (HBV DNA) in the blood and the liver while exhibiting undetectable HBV surface antigen (HBsAg). The molecular mechanisms underlying this occurrence are still not completely understood. This study investigated the prevalence of OBI in a high-risk Australian population and compared the HBV S gene sequences of our cohort with reference sequences. Serum from HBV DNA positive, HBsAg negative, and hepatitis B core antibody (anti-HBc) positive patients (study cohort) were obtained from samples tested at SEALS Serology Laboratory using the Abbott Architect, as part of screening and diagnostic testing. From a total of 228,108 samples reviewed, 1,451 patients were tested for all three OBI markers. Only 10 patients (0.69%) out of the 1,451 patients were found to fit the selection criteria for OBI. Sequence analysis of the HBV S gene from 5 suspected OBI infected patients showed increased sequence variability in the ‘a’ epitope of the major hydrophilic region compared to reference sequences. In addition, a total of eight consistent nucleotide substitutions resulting in seven amino acid changes were observed, and three patients had truncated S gene sequence. These mutations appeared to be stable and may result in alterations in HBsAg conformation. These may negatively impact the affinity of hepatitis B surface antibody (anti-HBs) and may explain the false negative results in serological HBV diagnosis. These changes may also enable the virus to persist in the liver by evading immune surveillance. Further studies on a bigger cohort are required to determine whether these amino acid variations have been acquired in the process of immune escape and serve as markers of OBI.     

Seropositivity for hepatitis B virus, vaccination coverage, and vaccine response in dentists from Campo Grande, Mato Grosso do Sul, Brazil

This study investigated the seropositivity for hepatitis B virus (HBV), the vaccination index, and the vaccine response index in dentists from Campo Grande, MS. Blood samples from 474 dentists (63.7% women and 36.3% men), with a mean age of 38.5 +/- 10.5 years were analyzed by enzyme-linked immunosorbent assay to detect the serological markers: HBsAg, anti-HBs, and anti-HBc. The HBsAg positive samples were tested for anti-HBc IgM, HBeAg, and anti-HBe. A total of 51 (10.8%) dentists showed seropositivity for HBV. Three (0.6%) were HBsAg/anti-HBc/anti-HBe positive, 43 (9.1%) were anti-HBc/anti-HBs positive, and 5 (1.1%) had only anti-HBc. Viral DNA was detected by polymerase chain reaction in 9 (17.6%) out of 51 HBV seropositive samples. A vaccination index of 96.6% (458/474) was observed, although 73.1% (335/458)completed the three-dose schedule. Excluding 46 HBV seropositive individuals from 458 that reported vaccination, 412 were analyzed for vaccine response index. It was observed that 74.5% (307/412) were anti-HBs positive; this percentage increased to 79.1% when three doses were administered. The results showed a high vaccination index and a good rate of vaccine response; however, the failure in completing the three-dose schedule and the occurrence of HBV infection reinforce the need for more effective prevention strategies.     

Risk of vertical transmission of hepatitis B virus in Tunisia

The risk of vertical transmission of hepatitis B virus (HBV) varies with type of viral endemicity, degree of maternal infection and genomic characteristics of the virus. The aim of this study is to estimate this risk in Tunisia using serological and molecular methods to evaluate HBV replication, to determine viral genotypes and to detect presence of occult hepatitis in 2709 pregnant women. Serological markers were detected by ELISA methods, Genotype was determined by PCR-RFLP and occult hepatitis by nested-PCR. Four percent of women were positive for HBsAg; only 3% of them were also positive for HBeAg. Viral replication, over than 10(3) copies/ml, was detected in 61% of positive HBsAg patients. Three viral genotypes were detected: D (95%), B (3%) and A (3%). Occult hepatitis was detected in 4% of sera with "anti-HBc isolated" profile. In conclusion, the risk of vertical transmission of HBV exists in Tunisia. It increases by frequency of precore mutants, predominance of the genotype previously associated with high levels of replication and possibility of occult hepatitis B. These results show the importance of screening by serological HBV markers systematically during pregnancy with evaluation of viral replication in order to prevent vertical risk by efficient tools.     

Detection of hepatitis B virus in bone allografts from donors with occult hepatitis B infection

The implementation of nucleic acid testing in donor screening has improved the safety of tissue allografts. Although infectious disease transmission can be considered a rare event, the detection of occult hepatitis B infection remains challenging. The studies concerning this risk are mainly based on testing blood specimens. This work shows the correlation between results of samples obtained from donor blood and the corresponding tissue washing solution. Hepatitis B virus deoxyribonucleic acid was detected both in bone allografts from donors with serological profiles associated to active hepatitis B infection and occult hepatitis B infection. These results suggest that hepatitis B virus seems to concentrate in bone marrow even when a low viral load is present in peripheral blood. Even detection at molecular level is not enough to avoid the risk of hepatitis B virus transmission and a multiparametrical evaluation is required in tissue donor screening. The role of clinicians in recognition and reporting of allograft-associated infections is a major concern for the acquisition of experience to be applied in risk control of disease transmission.     

Seroepidemiology of hepatitis B virus infection and high rate of response to hepatitis B virus Butang vaccine in adolescents from low income families in Central Brazil

In order to evaluate the seroepidemiology and response to Butang vaccine in adolescents from low income families in Central Brazil, blood samples of 664 adolescents were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) markers, and multiple logistical regression analysis was carried out to determine variables associated with hepatitis B virus (HBV) infection markers. further, three 20 microg Butang vaccine doses were offered to all susceptible individuals (n = 304). Among those who accepted them (n = 182), the seroresponse was evaluated in 170 individuals by quantitative anti-HBs. an overall hbv prevalence of 5.9% was found: four adolescents were HBsAg positive, 24 were anti-HBc, anti-HBs-reactive, and 11 were anti-HBc only. The analyse of risk factors showed that age 16-19 years, place of birth outside Goiás, school B and body piercing were statistically associated with HBV infection markers (p < 0.05). All 170 adolescents responded to Butang, and a geometric mean titer (gmt) of 4344 mUI/ml was obtained. these results reinforce the importance of hepatitis b vaccine in adolescents despite of the hbv regional endemicity, and suggest that three doses of 20 microg of the Butang should guarantee protective anti-hbs levels to individuals at a critical time for hepatitis b acquiring such as latter adolescence and adulthood.