Hepatitis e virus infection in fulminant hepatitis patients and an apparently healthy population in Bangladesh

This is the first study comparing hepatitis E virus (HEV) infection in Bangladesh in fulminant hepatitis (FH) patients presumed to have a viral cause and in the apparently healthy population. Sera from 22 FH patients were analyzed for antibodies to hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C and D viruses, and HEV and for hepatitis B surface antigen (HBsAg). Anti-HEV immunoglobulin M (IgM) was detected in the sera of 63.6% of patients, whereas 35.7% were positive for HBsAg. A high prevalence of HEV infection (83.3%) was noted in the HBV carriers. Serum samples from 273 apparently healthy individuals were tested for antibodies to HAV and HEV. Anti-HEV IgM was detected in 7.3% of the samples. The seroprevalence of HAV differed from that of HEV in the same population because all samples were negative for anti-HAV IgM. These data indicate that HEV infection is highly endemic in Bangladesh.     

Spectrum of viral hepatitis in thalassemic children receiving multiple blood transfusions.

AIM: To investigate the prevalence of infection with hepatitis viruses in children with thalassemia receiving multiple blood transfusions. METHODS: Sera from 50 children with thalassemia aged 5-15 years (30 boys), who had each received over 80 units of blood, were evaluated for the presence of markers for hepatitis A virus (HAV; IgG and IgM anti-HAV), hepatitis B virus (HBV; HBsAg, and IgG and IgM anti-HBc), hepatitis C virus (HCV; IgG and IgM anti-HCV, and HCV RNA) and hepatitis E virus (HEV; IgG and IgM anti-HEV). IgM anti-hepatitis D virus (HDV) was looked for only in HBsAg or IgM anti-HBc positive sera. RESULTS: No child had evidence of recent HAV or HDV infection. IgG anti-HAV was positive in 12 children. One patient had acute HBV infection. Nine patients were HBsAg-positive. HCV infection was present in 15 cases; six of them were HCV RNA positive, and three had superinfection with hepatitis B. Recent HEV infection was present in 5 cases. CONCLUSION: Thalassemic patients receiving multiple blood transfusions often acquire hepatitis B (20%) and C (30%) infections. Recent hepatitis E infection was documented in 10% in this one-point study.     

Prevalence of hepatitis B and C markers among refugees in Athens

AIM: To assess the prevalence of hepatitis B and C serological markers in a population of refugees living in Athens. METHODS: One hundred and thirty refugees (81 males and 49 females, mean age +/-SD: 31.7+/-8 years) were included in the study. The hepatitis B virus surface antigen (HBsAg), the hepatitis B virus core antibody (anti-HBc) and the hepatitis C virus antibody (anti-HCV) were detected using a third-generation immunoassay. RESULTS: Twenty individuals (15.4 %) were HBsAg positive and 69 (53.1 %) were anti-HBc positive. The prevalence of HBsAg and anti-HBc was higher among refugees from Albania and Asia (statistical significant difference, P<0.008 and P<0.001 respectively). The prevalence of these markers was found irrelevant to age or sex. Anti-HCV was detected in the serum of 3 individuals (2.3 %). No differences among age, sex or ethnicity regarding anti-HCV prevalence were found. CONCLUSION: It can be concluded that refugees living in Athens are an immigrant population characterized by a high incidence of HBV infection. The prevalence of HBV markers is higher among refugees from Albania and Asia. It is therefore believed that the adherence to general precautions and the initiation of HBV vaccination programs will be necessary in the future, especially in these communities. Although the prevalence of HCV infection seems to be relatively low, extended epidemiological surveys are needed to provide valid results.     

Changing epidemiology of HCV and HBV infections in Northern Italy: a survey in the general population

AIM: To evaluate the hepatitis B virus (HBV) and the hepatitis C virus (HCV) epidemiology in the general population of Northern Italy, a cohort of 965 subjects, all residents (including 47 immigrants), were anonymously tested for HBV and HCV infections. MATERIAL AND METHODS: Serum samples were assayed for anti-HCV and anti-HBV markers by enzyme-linked immunosorbent assay and for HCV-RNA by polymerase chain reaction, and the positive cases were genotyped. HBsAg-positive cases were assayed for HBeAg/anti-HBe, whereas HBsAg negatives were tested for both anti-HBc and anti-HBs. RESULTS: The overall prevalence of anti-HCV was 2.6%, with a bimodal distribution characterized by the highest prevalence (12%) in subjects over 75 years old. None of the subjects under 25 years old was anti-HCV positive. Anti-HCV positivity was similar in males and females (2.4% vs. 2.7%). HCV-RNA was positive in 40% of cases and genotype 1 was the most common. The HBsAg prevalence was 1%, with a significant difference according to country of origin (0.8% in Italian subjects vs. 6.4% in immigrants, P=0.01). HBsAg positivity increased significantly with age (R2=0.57, P<0.02). The overall percentages for the prevalence of isolated anti-HBs, anti-HBs+/anti-HBc+, and isolated anti-HBc were 23.8%, 8.4%, and 4.2%, respectively. CONCLUSIONS: Our study provides a new picture of HCV and HBV epidemiology in Northern Italy, with these features: (1) a cohort effect showing a reduction of HCV infection in the elderly, possible due to age-related mortality; (2) an unchanged overall prevalence of HBV infection, despite continuing immigration of subjects from endemic countries.     

Prevalence of hepatitis B among pregnant women assisted at the public maternity hospitals of São Luís,Maranhão,Brazil

IntroductionHepatitis B virus (HBV) infection is an important worldwide public health problem. In Brazil, the Ministry of Health estimates that 15% of the population has had contact with HBV, and that the mean rate of chronic carriers in Northeastern Brazil is around 0.5%.ObjectiveThe aim of this study was to assess the prevalence of HBV markers in pregnant women receiving prenatal care at the public maternity hospitals of São Luís.MethodsDemographical and epidemiological data were collected from 541 pregnant women according to the research protocol. Blood samples were collected, and the anti-HBc test was performed first. If positive, the sample was subsequently tested for HBsAg and anti-HBs. All HBsAg and/or anti-HBc positive samples were additionally tested for HBV-DNA.Results40 (7.4%) pregnant women turned out positive for anti-HBc. Of those, five (0.9%) were HBsAg positive, four (0.7%) were anti-HBc positive with negative HBsAg and anti-HBs, and 31 (5.7%) were positive for anti-HBc and anti-HBs. Anti-HBc positivity was associated with family history of hepatitis and education level below 11 years of schooling. HBV-DNA was positive in only one HBsAg-positive sample. There was no HBV-DNA positivity among HBsAg negative samples.ConclusionsThe prevalence of HBsAg in pregnant women in this study confirmed that São Luís is a low endemicity area. Occult hepatitis B was not detected in these samples.     

Low rate of occult hepatitis B virus infection among anti-HBc positive blood donors living in a low prevalence region in Brazil

OBJECTIVE: The aim of this study was to determine the rate of occult hepatitis B virus (HBV) infection among blood donors living in a geographic region of low (5.6%) anti-HBc prevalence. SUBJECTS AND METHODS: Sera from 150 candidate blood donors whose blood was rejected due to total anti-HBc reactivity (despite absence of HBsAg) were tested for anti-HBs and IgM anti-HBc antibodies, as well as for HBeAg/anti-HBe. Serum HBV DNA was sought by using a PCR assay able to amplify part of the surface gene. Viral load was measured in the PCR positive samples. RESULTS: The pattern 'anti-HBc alone' (without HBsAg and anti-HBs antibodies) was found in 64 (42.7%) subjects. IgM anti-HBc and anti-HBe antibodies were detected in 2 (1.3%) and 80 (53.3%) samples, respectively. No sample was HBeAg-reactive. HBV DNA was repeatedly found in five (3.3%) samples, three of which were anti-HBs positive and two anti-HBs negative. All five HBV DNA positive samples showed a low viral load (<1000copies/ml). CONCLUSIONS: The data indicated a low rate of occult infection among anti-HBc positive, HBsAg negative blood donors living in a region of low prevalence of infection. Viral load was very low in all HBV infected subjects.     

The prevalence of viral hepatitis among the Hmong people of northern Thailand

Sera from 269 Hmong people (102 males and 167 females, with mean age 35.4 years, range 16-63 years) were examined in order to determine the seroprevalence of hepatitis virus infection. The seroprevalence rates for HAV (hepatitis A virus), HBV (hepatitis B virus), HCV (hepatitis C virus), HDV (hepatitis D virus), HEV (hepatitis E virus), HGV (hepatitis G virus) and TTV (TT virus) infection were 87.8% (n=140), 76.0% (n=150), 2.0% (n=150), 0.7% (n=150), 6.5% (n=139), 5.3% (n=94) and 25.6% (n=121) respectively. The rate for carriers of HBV (HBsAg) was 13.8% (20.5% in males and 9.6% females) with a peak prevalence in the 21-40 year age group. A high rate of HAV seropositivity was found among the younger subjects. The rate of HEV seroprevalence was low. The prevalence of TTV-DNA was high with no difference between the sexes. HGV-RNA prevalence was low and seen primarily in males. This study indicates that the Hmong people are endemically infected with HAV and HBV infection and should be considered for targeted vaccination. The role of TTV and HGV in producing illness and hepatic disease has yet to be determined in this population.     

Prevalence of antibodies against hepatitis A virus, hepatitis B virus, and Treponema pallidum in Mauritius.

A seroepidemiological study on the prevalence of antibodies against hepatitis A virus (HAV), hepatitis B virus (HBV) and Treponema pallidum was conducted in various groups of the population of the state of Mauritus (Islands of Mauritus and Rodrigues). 618 sera were tested. The overall prevalence of anti-HAV was 86.1% and yielded and age-dependent increase. Serological evidence for acute or chronic HBV infection was found in 3.8%; 4.5% were positive for anti-HBc alone, and in 12.6% past HBV infection was detected. No age- or sex-dependent increase in the prevalence of anti-HBc was found. There were differences in the anti-HBc prevalence among the various groups of population ranging from 5.9 (flight personnel) to 58.3% (prison inmates). Treponemal antibodies were detected in 6.0% and showed a fairly marked age-dependent increase. Our study suggests that vaccination programmes against HAV and HBV would be beneficial for the Mauritian population.     

HAV and HBV seroprevalence in 1,000 patients with chronic HCV infection in a Tertiary Care Center in São Paulo,Brazil

Background. Patients with chronic HCV infection and superinfection by hepatitis A virus (HAV) or hepatitis B virus (HBV) have higher morbidity and mortality when compared with those without HCV infection. Therefore, HAV and HBV active immunization has become mandatory in this population and hence their serological markers must be determined. The aim of this study was to evaluate the prevalence of serological markers of HAV and HBV infection in patients with chronic HCV.Material and methods. One thousand chronic HCV patients at the University of Säo Paulo School of Medicine were evaluated for the prevalence of serological markers of HAV and HBV infection.Results. Anti-HAV IgG was positive in 92.3% of patients. When stratified by age, anti-HAV IgG was found in 61% of patients between 20-29 years, 70% on patients between 30-39 years, 85% on patients between 40-49 years, 94% on patients between 50-59 years, and in 99% on patients over 60 years of age. Anti-HBc IgG was positive in 244 patients (24%). Stratified by age, in 4.3% of patients between 20-29 years, 17% 30-39 years, 21% 40-49 years, 24% 50-59 years, and in 28% of patients over 60 years. Of the 244 anti-HBc IgG positive patients, 0.8% were HBsAg positive, 8.5% were anti-HBc IgG isolated and 16% were also anti-HBs positive.Conclusions. In conclusion, the prevalence of anti-HAV IgG was similar to the general Brazilian population. However, anti-HBc IgG was higher in our patients, when compared to general population of Western countries, emphasizing the importance of immunization programs for this population.     

Significant increase in HBV, HCV, HIV and syphilis infections among blood donors in West Bengal, Eastern India 2004-2005： Exploratory screening reveals high frequency of occult HBV infection

AIM： To evaluate the prevalence of markers of hepatitis B virus （HBV） and hepatitis C virus （HCV） and human immunodeficiency virus （HIV） among blood donors in Kolkata, Eastern India for two consecutive years and to conduct a pilot study to explore the presence of HBV DNA among hepatitis B surface antigen （HBsAg） negative but anti-HBc positive blood donors.
METHODS： Seroprevalence of HBsAg, anti-HCV and anti-HIV was studied among 113051 and 106695 voluntary blood donors screened in 2004 and 2005, respectively. Moreover, a pilot study on 1027 HBsAg negative donors was carried out for evaluating the presence of HBV DNA by PCR on HBsAg negative/anti- HBc positive donors.
RESULTS： A statistically significant increase in the prevalence of HBV （1448 vs 1768, P 〈 0.001）, HIV （262 vs 374, P 〈 0.001）, HCV （314 vs 372, P = 0.003） and syphilis （772 vs 853, P = 0.001） infections was noted among blood donors of Kolkata West Bengal in 2005 as compared to 2004. Moreover, the exploratory study on 1027 HBsAg negative donors revealed that 188 （18.3%）of them were anti-HBc positive out of which 21% were positive for HBV DNA.
CONCLUSION： The findings of this study underscore the significantly increasing endemicity of hepatitis viruses, syphilis and HIV among the voluntary blood donors of our community. The pilot study indicates a high rate of prevalence of HBV DNA among HBsAg negative/anti-HBc positive donors and thus emphasizes the need for a more sensitive and stringent screening algorithm for blood donations.     

Decrease of hepatitis A and B virus infections in the population of Okinawa, Japan

In 1988 1282 serum samples were collected from healthy Japanese persons living on Hateruma Island (574 samples) and Iriomote Island (708 samples) in Okinawa, Japan. Serological markers of hepatitis B virus (HBV) infection [hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc) were investigated and the findings compared with samples taken in 1980 on Hateruma Island and in 1970 and 1980 on Iriomote Island. The samples collected in 1988 on Iriomote Island were also tested for antibody to hepatitis A virus (anti-HAV) and the findings compared with the results of the 1970 and 1980 surveys. The overall prevalence of HBsAg and anti-HBc was 3.7 and 64.8% for Hateruma Island and 3.8 and 44.9% for Iriomote Island. In both areas the overall prevalence of anti-HBc was lower than in 1980, the decrease being significant for the 10-19 year age group on Hateruma Island and the age groups under 39 years on Iriomote Island. The overall prevalence of anti-HAV had fallen to 50.9%. This remarkable decrease had occurred in children and young adults. These data suggest that Virus A (HAV) and HBV infections have dramatically decreased among children in Okinawa within the past 2 decades.     

慢性乙型肝炎病毒感染者家族隐匿性乙型肝炎病毒感染的调查

目的 了解慢性HBV感染者家族隐匿性HBV感染的发生率及其与HBV标志物、年龄和性别等的关系.方法 ELISA方法检测慢性HBV感染者家族成员的HBV血清学标志物,套式PCR法检测136例HBsAg阴性家族成员的血清HBV DNA,并将隐匿性HBV感染者和HBsAg、HBV DNA均阴性者分别作为试验组和对照组进行HBV标志物、年龄、性别和生物化学检测结果的比较.两组均数比较采用t检验.率的比较采用χ~2检验或Fisher确切概率法检验.结果 在52个慢性HBV感染者家族中共检测到92例HBsAg阳性者和136例HBsAg阴性者,其中15例为隐匿性HBV感染者,慢性HBV感染者家族HBsAg阳性率和隐匿性HBV感染的发生率分别为40.4%和11.0%,15例隐匿性HBV感染者中有7例抗-HBc阳性(χ~2=5.341,P=0.02),但隐匿性HBV感染的存在与年龄、性别等无关.结论 HBV感染存在家庭聚集现象,且在其家族中存在隐匿性HBV感染,并在抗-HBc阳性者中发生率较高.     

Hepatitis B virus DNA in the serum of Sardinian blood donors negative for the hepatitis B surface antigen

The high endemicity of hepatitis B virus (HBV) infection and liver disease in Sardinia led us to assess the occurrence of HBV DNA in 1,411 sera of two selected groups of hepatitis B surface antigen (HBsAg)- negative blood donors: 793 with abnormal serum alanine aminotransferase (ALT) and 618 with normal serum ALT values (determined during routine testing of their blood donation). HBV DNA sequences were detected by dot-blot hybridization in 68 of 793 subjects (9%) with abnormal ALT but only in three of 618 subjects (0.5%) with normal ALT. HBV-core antibody (anti-HBc) was detected in 338 of 793 subjects (43%) with abnormal ALT as well as in 125 of 618 subjects (20.2%) with normal ALT. Among the 71 subjects positive for serum HBV DNA, 22 (31%) were positive for anti- HBc, while 49 (69%) were negative for all serologic markers of HBV infection. Thus, a high frequency of anti-HBc in apparently healthy HBsAg-negative individuals and a high prevalence of serum HBV DNA in the absence of immunologic markers of HBV infection suggest the existence of genetic variants of HBV that may be responsible for some of the presumed NANB hepatitis encountered in Sardinia and possibly other areas of high endemicity for HBV.     

Epidemiology and transmission of hepatitis B and C viruses in Kazakhstan

AIM: To investigate the epidemiology of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in the two major ethnic groups in Kazakhstan. METHODS: A cross-sectional prospective study of HBV and HCV seroprevalence was performed among individuals born in Kazakhstan with no history of chronic hepatitis or liver disease. RESULTS: There were 290 volunteers (140 Russians and 150 Kazakhs) aged 10 to 64 years, males accounted for 46%. Active HBV infection (HBsAg positive) was present in 3.8%, anti-HBc in 30%. The prevalence was similar in females and males (33% vs 25%) (P = 0.18). The prevalence of anti-HBc increased from 19% in 10-29 years old volunteers to 53% in 50-years and older volunteers. The prevalence of HBV infection was higher in married than in single adults (38% vs 26%, respectively) (P = 0.2) and more common in Kazakhs (35%) than in Russians (24%) (P = 0.07). HCV infection was present in 9 subjects (3.2%), 5 of them also were positive for anti-HBc in the absence of HBsAg. CONCLUSION: The frequency of active HBV infection (3.8%) coupled with a high prevalence of HBV exposure in those > 50 years of age increases with age, which suggests that horizontal transmission likely relates tothe use of contaminated needles. The low prevalence of HCV infection suggests that HBV and HCV are acquired differently in this group of subjects.     

Changing prevalence of hepatitis B virus in urbanized Australian Aborigines

Serological surveys of desert or rural Australian Aboriginal settlements report up to 85% positivity for hepatitis B virus (HBV) markers. We report the results of two cross-sectional HBV surveys carried out 5 years apart in the bi-racial town of Condobolin, New South Wales (population 3086; 14% Aborigines). In 1983–84, none of the 310 non-Aborigines tested were hepatitis B surface antigen (HBsAg) positive but 7.2% were positive for hepatitis B core antibody (anti-HBc). Among Aboriginal subjects, 57.6% had detectable HBV markers and 16.9% were HBsAg positive. In 1987–88, no non-Aborigines were HBsAg positive and only 1% (of 422 individuals) had anti-core antibodies. In contrast, 36% of Aboriginal subjects had HBV markers and 6% were HBsAg positive. No significant difference in detectable HBV markers was found among 98 Aborigines who were included in both surveys. Migration was the main factor influencing the HBV prevalence between the two surveys. Clustering of HBsAg carriers occurred within households and the likely mode of infection was intrafamilial horizontal childhood transmission. There was a significant association between HBV markers and tattooing in Aborigines (P≤ 0.02). Overall, HBV markers were less frequent in this population than in other desert or rural Aboriginal populations surveyed. The prevalence of HBV infection in non-Aboriginal households was not significantly different from that in the Australian Caucasian population.     

Markers of hepatitis viruses and human T-lymphotropic virus types I/II in patients who have undergone open-heart surgery: evidence of increased risk for exposure to HBV and HEV

BACKGROUND: Open-heart procedure is characterized by a high-risk for contracting blood-borne infections. We evaluated the prevalence of several markers of hepatitis viruses (B-E) and human T-cell lymphotropic virus types I/II (HTLV-I/II) in a consecutive series of patients who had undergone open-heart surgery. METHODS: 204 patients and 158 selected age- and sex-matched healthy volunteers were investigated. Samples were collected at least 6-12 months postoperatively. Commercial enzyme immunoassays and confirmatory immunoblot assays for HCV, HEV and HTLV-I/II were used. RESULTS: None of the subjects tested positive for antibodies to HTLV-I/II. Prevalence of markers of past HBV infection and antibodies to HEV (anti-HEV) were higher in patients than in healthy controls (anti-HBc: 45.1% vs. 31%, p=0.009; anti-HBs: 31.9% vs. 22.2%, p=0.02; anti-HBe: 32.4% vs. 10.1%, p=0.000; anti-HEV: 5.4% vs. 0%, p=0.008). HBsAg and antibodies to HCV did not differ between the groups. CONCLUSIONS: HTLV, HBsAg and HCV infection markers did not differ between patients and healthy controls. However, patients had significantly increased prevalence of markers of previous HBV infection suggesting that an intensive vaccination schedule against HBV preoperatively might be helpful in minimizing the risk. The increased prevalence of anti-HEV in cardiac patients requires further investigation. Prospective studies are needed in order to definitely address whether the high prevalence of exposure to HBV and HEV infections in patients who had undergone open-heart surgery is procedure-related or not and whether it has any impact on morbidity of these patients.     

广州市自然人群病毒性肝炎血清流行病学研究

目的了解广州市自然人群病毒性肝炎的血清流行病学特征。方法采取分层多级整群系统随机抽样方法抽取研究对象,对其作流行病学个案调查,并应用酶联免疫吸附试验（ELISA法）检测病毒性肝炎各感染标志物。结果广州市自然人群HAV、HBV、HCV、HDV、HEV、HGV感染率分别为74．47％、64．10％、0．65％、0．13％、1．69％和0．65％;HAV、HBV和HEV的感染率在老城区、新城区和郊市区中的差异有高度显著性意义（P〈0．01）,而HCV、HDV和HGV的差异无显著性意义（P〉0．05）;HBV感染率在男女之间差异有高度显著性意义（P〈0．01）,HCV感染率在男女之间差异有显著性意义（P〈0．05）,而HAV、HDV、HEV和HGV的感染率则无性别差异（P〉0．05）;HAV、HBV、HCV、HDV、HEV、HGV最低感染年龄分别为2岁、2岁、20岁、31岁、5岁和13岁,最高感染年龄分别为90岁、86岁、46岁、67岁、74岁和71岁;HAV、HBV和HEV感染率均与年龄呈正相关（P〈0,01、P〈0,01和P〈0．05）。结论广州市自然人群各型病毒性肝炎感染具有不同的流行病学特征,其中HAV和HBV的感染率较高,HCV、HDV、HEV和HGV的感染水平则较低。     

Etiology of endemic viral hepatitis in urban North India

This study was carried out to determine the presence of markers of hepatitis viruses in patients with acute liver disease. Coinfection of HAV, HBV, HCV, and HEV was studied. Sera from 306 patients with a clinical diagnosis of acute liver disease were tested for the presence of anti-HAV antibody, HBsAg, anti-HBc antibody, anti-HBs antibody, anti-HCV antibody and IgM anti-HEV antibody by ELISA. Liver function tests were correlated with the presence of infection. Of the 306 cases, 7 (2.3%) had IgM anti-HAV, 9 (2.9%) had IgM anti-HBc, 37 (12.1%) had HBsAg, 84 (27.4%) had anti-HBs, 10 (3.3%) were HCV infected and 63 (20.6%) had IgM anti-HEV. There was no significant difference in the clinical and liver function profiles of infected and uninfected patients. Similarly, no difference was observed in cases coinfected with more than one virus compared with those infected with a single pathogen. HEV had the highest prevalence amongst our cases. There was no difference in the clinical profiles of patients with non-A, non-B, non-C, non-E hepatitis by antibody assays and testing for viremia could be helpful in making the correct diagnosis.     

Epidemiological impact of mandatory vaccination against hepatitis B in Italian young adults

Background

Viral hepatitis caused by hepatitis B virus (HBV) is a leading cause of acute and chronic liver diseases worldwide.

Objectives

In Italy, a mandatory vaccination policy was introduced in 1991 and was established for all newborns and 12-year-old individuals. In 2004, vaccination of 12-yearold adolescents was discontinued, and that of infants was maintained.

Patients and Methods

We evaluated the seroprevalence of HBV markers in 806 individuals, who were vaccinated at birth or at 12 years of age, to assess the effectiveness of the national policy against HBV.

Results

The overall prevalence of anti-HBs antibodies was 90.32% (95% confidence interval [CI]: 88.28–92.36%); 2.23% (95% CI: 1.21–3.25%) of the subjects were positive for both antibodies to HBsAg (anti-HBs) and antibodies to hepatitis B core antigen (anti-HBc), whereas 5.83% (95% CI 4.21–7.45) of the subjects were negative for all markers tested. Further, 1.61% (95% CI: 0.74–2.48%) of the subjects were positive for hepatitis B surface antigen (HBsAg).

Conclusions

Our data provide additional evidence that HBV vaccination can confer long-term immunity when performed at birth and when performed for healthy adolescents; moreover, the results show the effectiveness of the application of a national vaccination strategy.