Population-based study on the seroprevalence of hepatitis A, B, and C virus infection in Amsterdam, 2004

In order to enhance screening and preventive strategies, this study investigated the seroprevalence of hepatitis A, B, and C in the general adult urban population and in subgroups. In 2004, sera from 1,364 adult residents of Amsterdam were tested for viral markers. Sociodemographic characteristics were collected using a standardized questionnaire. For hepatitis A, 57.0% was immune. Of first-generation immigrants from Turkey and Morocco, 100% was immune. Of all Western persons and second-generation non-Western immigrants, approximately half was still susceptible. For hepatitis B, 9.9% had antibodies to hepatitis B core antigen (anti-HBc) and 0.4% had hepatitis B surface antigen. Anti-HBc seroprevalences were highest among first-generation immigrants from Surinam, Morocco, and Turkey, and correlated with age at the time of immigration, and among men with a sexual preference for men. Seroprevalence among second-generation immigrants was comparable to Western persons. The seroprevalence of hepatitis C virus antibodies was 0.6%. In conclusion, a country with overall low endemicity for viral hepatitis can show higher endemicity in urban regions, indicating the need for differentiated regional studies and prevention strategies. More prevention efforts in cities like Amsterdam are warranted, particularly for hepatitis A and B among second-generation immigrants, for hepatitis B among men with a sexual preference for men, and for hepatitis C. Active case finding strategies are needed for both hepatitis B and C.     

Seroepidemiology of hepatitis A among Greek children indicates that the virus is still prevalent: Implications for universal vaccination

A national cross‐sectional seroprevalence survey was conducted in order to evaluate the current seroepidemiology of hepatitis A among 1,383 children, aged 0–14 years, residing in Greece. Stratification of the study population was conducted according to age and area of residence. Sera from study participants were tested for the presence of anti‐HAV IgG antibodies. Immigrant children, as well as children residing in rural areas, had lower immunization rates. Among unvaccinated children, the seroprevalence rate of anti‐HAV was 17.1%. Nationality was shown to have a marginally significant effect since non‐immunized immigrant children had a higher seroprevalence rate (22.4% vs. 15.9%, OR = 1.52, P = 0.064). Significant differences between geographic areas for both vaccination coverage and natural immunity were observed. The study findings indicate that hepatitis A is prevalent in Greece and therefore universal infant hepatitis A immunization should be implemented. J. Med. Virol. 81:582–587, 2009 © 2009 Wiley‐Liss, Inc.     

Seroprevalence of hepatitis E virus infection in rural and urban populations,Tunisia

Hepatitis E virus (HEV) is one of the leading agents of acute hepatitis. This study investigated the prevalence and risk factors of HEV infection in the Tunisian adult general population, either in blood donors (n = 687) or in patients hospitalized for acute hepatitis (n = 202). The mode of transmission differed between these two populations: contact with animals and living in a rural habitat were the main risk factors for being in contact with HEV in asymptomatic blood donors, while HEV was contracted through contaminated water in symptomatic cases. HEV seroprevalence in adult blood donors in Tunisia was relatively low (5.4%) and increased with age.     

Lack of complement-dependent cytolytic antibodies in hepatitis A virus infection

Sera collected from patients with acute hepatitis A virus (HAV) infection and convalescent sera were examined for cytolytic activity against HAV-infected human-embryo lung fibroblasts (HAV carrier fibroblasts). Using the 51chromium release assay, no complement dependent antibody mediated cytolytic activity against HAV carrier cells could be detected. In control experiments with identical cell strains, anti-herpes simplex virus (HSV) positive sera and complement caused specific lysis of HSV type 1 infected target cells. The data presented here do not support the hypothesis that in the possible immunopathogenesis of HAV infection, complement-dependent cytolytic antibodies play an essential role.     

甲型肝炎病毒的纯化及其单抗的制备

应用不连续蔗糖／甘油密度梯度超速离心的方法，从培养细胞中纯化甲肝病毒（Ｈｅ－ｐａｔｉｔｉｓＡＶｉｒｕｓ，ＨＡＶ）。纯化的ＨＡＶ抗原经ＳＤＳ－ＰＡＧＥ电泳分析，获得三条带：ＶＰ１（３４０００），ＶＰ２（３００００）和ＶＰ３（２６０００）。用纯化的ＨＡＶ抗原免疫Ｂａｌｂ／ｃ小鼠，将已免疫小鼠的脾细胞与ＳＰ２／０细胞融合，获得６株分泌抗ＨＡＶ单克隆抗体的杂交瘤。它们的培养上清和腹水的抗体滴度分别是５０～１０００和１０００～４０００。Ｉｇ亚类５株为ＩｇＧ１，１株为ＩｇＧ２ａ。采用间接的ＥＬＩＳＡ法分析ＨＡＶ抗原的抗原位点，结果表明ＨＡＶ抗原至少存在４个抗原位点，两个存在于ＶＰ１蛋白带，另两个分别存在于ＶＰ２和ＶＰ３蛋白带     

Seroprevalence of hepatitis E virus antibodies in different human populations of Cameroon

Hepatitis E virus (HEV) is a major cause of acute hepatitis worldwide. HEV infection is self-limiting, but fulminant hepatitis may occur with higher mortality rates. The aim of this study was to determine the seroprevalence of the HEV in three different populations in Cameroon and to assess alimentary risk factors of infection. A total of 903 individuals including 450 elderly people, 183 pregnant women, and 270 HIV-infected patients were enrolled during 2009-2015. All sera obtained were tested for the presence of anti-HEV antibodies with commercial enzyme-linked immunosorbent assay kits. The association between initial anti-HEV status and potential risk factors was assessed. Out of the 903 samples, 22.0% (199/903) were positives for anti-HEV immunoglobulin M (IgM), 5.8% (52/903) for anti-HEV IgG, and 3.5% (32/903) for both. The seropositivity for IgM was 7.0%, 13.1%, and 34.7%; meanwhile, the seropositivity for immunoglobulin G was 8.5%, 3.3%, and 5.1%, in HIV-infected patients, pregnant women, and the elderly population, respectively. Both antibodies were detected simultaneously in 2.2%, 1.6%, and 5.1% in HIV-infected patients, pregnant women, and the elderly population, respectively. No risk factors were significantly associated with HEV infection in these populations. This study showed a high prevalence of anti-HEV antibodies in three different populations in Cameroon.     

Changing seroepidemiology of hepatitis A virus infection in Taiwan

Hepatitis A antibody (anti-HAV) in serum was studied from June to October, 1984, by radioimmunoassay in 647 male and 553 female apparently healthy children under 15 years of age in Taipei City. The prevalence rate of anti-HAV was 27.0% in infants, decreased to around 1% during the preschool age, then increased and remained around 5% until 11-12 years of age, when another increase was noted, and reached 13.6% among the early teenagers. The age-specific prevalence of anti-HAV increased with age but differed in three age ranges, which reflected three apparently different calculated annual incidences. Compared with previous studies in Taipei, the results showed a significant reduction in the prevalence of anti-HAV in almost every age group from 3 to 14 years. This fact probably reflects the marked improvement of hygienic conditions and progress in health education in recent years, which reduced the exposure to HAV infection among young children. The age of primary infection in the children was older than in previous studies, and it is expected that the susceptibility of HAV will extend to early adulthood.     

Baseline seroepidemiology of hepatitis B virus infection in children in Taipei, 1984: a study just before mass hepatitis B vaccination program in Taiwan

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.     

Prevalence of antibodies against hepatitis A virus among children and adolescents in Germany

Since hepatitis A virus (HAV) infection during childhood is mostly asymptomatic, only seroprevalence studies can provide reliable information on incidence of HAV infection in children. The prevalence of anti-HAV antibodies was determined in sera taken in 2008 to 2010 from 1,645 children aged 0–17 years and in sera taken in 2010–2011 from 400 adult blood donors in Germany. For examination of trend over time, 715 sera collected between 1999 and 2006 from children at the age of 0–17 years within the federal state Thuringia were included. Antibody testing was carried out using the test kits ETI-AB-HAVK PLUS and ETI-HA-IGMK PLUS from DiaSorin. In children, the overall prevalence of antibodies was 10.8 %. After the seroprevalence declined from 8.8 % among the 0–2 year-olds to 2.4 % among the 3–4 year-olds, there was a significant increase to 20.5 % in the group of the 15–17 year-olds. Boys had with 12.7 % a significantly higher seroprevalence of anti-HAV antibodies compared to 8.8 % among girls. In adult blood donors, there was a HAV seroprevalence of 19.3 %. The likelihood of past infection or immunization within the age groups of children from 0 to 12 years differed significantly from that of adults. In conclusion, in Germany, only a small number of HAV infections occur in children, especially up to the age of 12 years. The proportion of susceptible children is greater than the proportion of susceptible adults. Thus, during outbreaks, the rate of infection among children would usually be higher than the rate among adults.     

Seroepidemiological study of hepatitis delta virus infection in Okinawa,Japan

A seroepidemiological study on hepatitis delta virus (HDV) infection was conducted in the Oki-nawan islands, the area of Japan where hepatitis B virus infection is most prevalent. The subjects of this study included 116 asymptomatic hepatitis B surface antigen (HBsAg) carriers, 48 patients with chronic hepatitis (CH), 19 with liver cirrhosis (LC), and 11 with hepatocellular carcinoma (HCC). Among the 194 serum samples examined, a total of 10 (5.2%) were anti-HDV sero-positive. Anti-HDV was detected in 2 (1.7%) of the 116 asymptomatic HBsAg carriers, in 3 (6.3%) of the 48 patients with CH, and in 5 (26.3%) of the 19 with LC. However, none of the patients with HCC had detectable anti-HDV. Eight of the 10 were born in the Miyako island group and the remaining 2 on the main island of Okinawa. Since the subjects included 34 individuals who were living and/or born in the Miyako islands, the positive rate of anti-HDV in the islands was 23.5%. This study demonstrates the existence of an endemic area of HDV infection in Japan. © 1995Wiley-Liss, Inc.     

Naturally occurring antibodies to the human syncytial virus in West Africa

The seroepidemiology of the human syncytial virus has been investigated by means of an indirect immunofluorescence test on 113 sera from normal antenatal women in Nigeria and 233 sera from normal individuals of both sexes and all ages in the Ivory Coast. It was found that 3.5% of samples from Nigeria and 19.7% of those from the Ivory Coast were positive. The findings are discussed.     

Prevalence of antibodies to human cytomegalovirus in urban, kibbutz, and Bedouin children in southern Israel

Prevalence of antibody to human cytomegalovirus (CMV) was determined in a sample of 860 healthy children aged 1-13 years in Beer Sheva, in the Negev region of Israel. Three groups of children were tested: (1) urban Jewish children of low, middle, and high socioeconomic levels; (2) 8 rural communes (kibbutz) in which children live in close contact with each other from the 6th week of life under good hygienic conditions and a high standard of living; (3) Bedouin, seminomadic Arabs living in relatively poor hygienic conditions in the desert. Kibbutz children showed a significantly higher rate of CMV seropositivity by the second year of life than urban Jewish and Bedouin children (76% versus 44% and 54% respectively) with a gradual increase to 94% in the 10-13-year age group. Among children living in urban populations a significantly higher prevalence of CMV seropositivity was associated with crowding, but not with other socioeconomic indicators (place of residence, country of origin, or education level of parents). A marked rise of CMV seropositivity with age was found in urban Jewish children in the 2-5-year age group during which time they attend nurseries (44% to 67%) and in the Bedouin children in the 6-9-year age group (59% to 86%) when they first attend school. The data suggest that close contact is of major importance in CMV infection in childhood. The clinical implications of early acquisition and high prevalence of CMV antibodies in the kibbutz setting are discussed.     

Hepatitis in Albanian children: molecular analysis of hepatitis A virus isolates

Hepatitis A is a common disease in developing countries and Albania has a high prevalence of this disease associated to young age. In spite of the occurrence of a unique serotype there are different genotypes classified from I to VII. Genotype characterisation of HAV isolates circulating in Albania has been undertaken, as well as the study of the occurrence of antigenic variants in the proteins VP3 and VP1. To evaluate the genetic variability of the Albanian hepatitis A virus (HAV) isolates, samples were collected from 12 different cities, and the VP1/2A junction amplified and sequenced. These sequences were aligned and a phylogenetic analysis performed. Additionally, the amino half sequence of the protein VP3 and the complete sequence of the VP1 was determined. Anti-HAV IgM were present in 66.2% of all the sera. Fifty HAV isolates were amplified and the analysis revealed that all the isolates were sub-genotype IA with only limited mutations. When the deduced amino acid sequences were obtained, the alignment showed only two amino acids substitutions at positions 22 and 34 of the 2A protein. A higher genomic stability of the VP1/2A region, in contrast with what occurs in other parts of the world could be observed, indicating high endemicity of HAV in Albania. In addition, two potential antigenic variants were detected. The first at position 46 of VP3 in seven isolates and the second at position 23 of VP1 in six isolates.     

人噬菌体抗体库的构建和甲肝抗体的筛选

目的　构建人噬菌体抗体组合文库,筛选人单克隆抗体。方法　用RTPCR扩增人全套抗体基因片段,克隆于pComb3载体,电转化E.coli形成噬菌体抗体库;以固相化抗原淘筛抗体库,ELISA鉴定噬菌体抗体。结果　17对免疫球蛋白引物全部能够扩增出目的片段;经数次电转化构建了库容为693×107的抗体库,滴度为8×1014PFU/ml,Fab基因重组率为40%。以单抗捕获的甲肝抗原淘洗3轮,出现特异性富集;阳性克隆经直接ELISA和竞争抑制性ELISA实验证实具有良好的抗甲肝抗原特异性,无交叉反应性。结论　成功构建了抗体组合文库,从中获得抗甲肝抗原的特异性人抗体。     

Seroprevalence of hepatitis C virus in haemophiliacs in Jamaica

Haemophilic patients (n = 90) and household contacts (n = 40) were tested for serological markers of hepatitis B virus (HBV), hepatitis C virus (HCV) and elevated serum aminotransferases using commercially prepared reagents. Of the haemophiliacs 41% (37/90) tested positive for antibodies to HCV (anti-HCV); 36% (32/90) antibodies to hepatitis B core antigen (anti-HBc); 54% (49/90) antibodies to hepatitis B surface antigen (anti-HBs) and 2% (2/90) hepatitis B surface antigen. On the other hand, 29% (26/90) of the patients and 90% (36/40) of the household contacts tested negative for all of the viral markers. Anti-HCV positivity in the haemophilic patients correlated positively with anti-HBc (p < 0.025). Increasing age (odds ratio 2.09; p < 0.01), severity of disease (odds ratio 6.2; p < 0.05) and the requirement for transfusion (odds ratio 3.2; p < 0.05) were risk factors for anti-HCV positivity. The presence of anti-HBc (odds ratio 3.8; p < 0.01) and coinfection with HCV and HBV also correlated positively with age (odds ratio 2.5; p < 0.01). The provision of anti-HCV screened donor blood and virally inactivated blood products for treatment of all haemophilic patients are goals that must be achieved.     

抗甲肝病毒人源基因工程全抗体分子在杆状病毒中的表达

目的 探讨人源抗甲型肝炎病毒全抗体分子在杆状病毒中的表达。方法 将获得的人源抗甲肝病毒中和性抗体Fab段基因克隆入含信号肽及Fc的杆状病毒表达载体中并在杆状病毒细胞中表达。结果 获得了中和性人源抗甲肝病毒全抗体分子的表达产物并进行了纯化，轻重链表达产物位置大小正确，HAFc16抗体能与具有中和活性的鼠抗甲肝病毒单克隆抗体产生竞争抑制反应，并能在体外中和甲肝病毒，另一株HAFc78抗体同样具有体外中和甲肝病毒的活性，但系抗不同位点的抗体。结论 获得的人源抗甲肝病毒全抗体分子表达产物具有很好的体外中和甲肝病毒的活性，且为抗不同位点的抗体，为这些抗体的进一步开发及应用打下了基础，为防止甲型肝炎暴发流行提供应急措施。     

从噬菌体抗体库筛选获得中和性人源抗甲型肝炎病毒Fab抗体

目的 研究人源抗甲型肝炎病毒基因工程抗体,为预防甲型肝炎病毒感染提供有效的方法。方法 采用噬菌体表面展示技术,从一名甲型肝炎恢复期病人的抗凝血中分离淋巴细胞,提取总ＲＮＡ逆转录后,用一组人ＩｇＧ Ｆａｂ特异性引物扩增。结果 克隆和表达了８株人源抗甲型肝炎病毒抗体Ｆａｂ段基因,经ＥＬＩＳＡ检测为特异性人抗甲型肝炎病毒Ｆａｂ段抗体。结论 该８株人源抗甲型肝炎病毒Ｆａｂ抗体都能与具有中和活性的鼠抗甲型肝炎病毒单克隆抗体产生竞争抑制反应,选其中的２株做体外中和实验,证明都有中和甲型肝炎病毒的活性。