Epidemiology of hepatitis B and C in Croatia

The incidence of HBV and HCV infection is hard to determine because of the high number of asymptomatic infections. According to data of the Croatian Institute of Public Health, there are 200 newly infected persons with hepatitis B and approximately the same number of newly identified HBsAg carriers occur each year. Accordingly, Croatia is among the countries with less than 2% of HBsAg carriers in the general population. In these circumstances, HBV infection is most often spread among adolescents and younger adults. The route of transmission is most often sexual (semen) or through the skin in high-risk groups. An increased risk of infection is found in newborns of HBsAg positive mothers, i.v. addicts, promiscuous individuals, male homosexuals, person in close contact with acutely ill or chronic HBsAg carriers, persons that come in contact with blood and other potentially contaminated body fluids, dialysis patients, patients with multiple blood transfusions, patients with transplanted organ or tissue, patients treated for hematologic malignancies and hemophilia, and persons who undergo acupuncture, tattooing or piercing, or travel to areas with a high prevalence of HBV infection. The estimated prevalence of HCV infection marker (anti-HCV) in the Croatian general population is more than 1% and the number of yearly infected with hepatitis C reported to the Croatian Institute of Public Health is around 200 cases. The highest incidence is found in the 20-40 age groups at a high risk of infection by the use of drug injection. At risk are persons who received transfusion of blood or blood products prior to the availability of blood screening of voluntary blood donors.     

Update on diagnosis, management, and prevention of hepatitis B virus infection

Acute and chronic hepatitis B virus (HBV) infection is a leading cause of liver disease worldwide. It is estimated that approximately 350 million people worldwide have chronic HBV infection and that 1 million persons die each year from HBV-related chronic liver disease. In the past decade, significant progress in the understanding of the molecular virology and pathogenesis of HBV infection has been made. In addition, effective treatment modalities have been developed for persons with chronic infection. Worldwide, prevention of HBV transmission has become a high priority. In 1992, the Global Advisory Group to the World Health Organization recommended that all countries integrate hepatitis B vaccine into national immunization programs by 1997. Currently, 80 countries have done so and several others are planning to. Many countries have reported dramatic reductions in the prevalence of chronic HBV infection among children born since the hepatitis B vaccine was introduced into infant immunization schedules. Recent reports from Taiwan indicate a reduction in the incidence of liver cancer among children as a result of widespread hepatitis B vaccination programs.     

Impact of an anti-hepatitis B virus (HBV) immunization program in patients undergoing dialysis in Havana, Cuba

The follow-up of HBV markers in selected high infection risk populations, in patients from the hemodialysis and peritoneal dialysis services was used to assess the effectiveness of a special vaccination program. Viral infection markers were studied in prevalence cross sections of the whole population of patients, and also by recording the reports of clinical cases of hepatitis B occurred during that period in those groups of patients. The prevention program consisted of the vaccination of all patients negative to the viral markers and the indication of vaccination for the new cases during the period of the kidney disease, just before the start of the treatment at the hemodialysis unit; besides all the persons susceptible to infection that had already been included in the program, regardless of the stage of the disease. The results show the benefit of the vaccination in these patients, but it is more effective in the period before the treatment with dialysis where there is a lower possibility of being exposed to the virus and the immune system is still competent. Once the program was established, after a follow up o 6 years, there have been no reports of new cases of hepatitis B and the incidence of the disease has been declining.     

Antiviral therapy for chronic hepatitis B in China

The vaccination program against hepatitis B virus (HBV) has greatly reduced the incidence of HBV infection. However, almost one-fourth of the HBV infected patients worldwide are still located in China. The healthcare burden from chronic HBV infection is a big challenge for the Chinese government and clinicians. Antiviral therapy plays a central role in controlling chronic HBV infection and preventing the disease progression. However, due to the specific economic and medical system issues, the first-line antiviral agents recommended by the AASLD and EASL have not been widely used for Chinese patients. In this review, we will discuss some key issues in the area of antiviral treatment for chronic hepatitis B in China.     

Epidemiology and prevention of hepatitis B virus infection

Hepatitis B virus (HBV) infection has been a major global cause of morbidity and mortality. The recognition of the problem led to a worldwide effort to reduce transmission of HBV through routine infant vaccination. HBV infection is the most common cause of chronic liver diseases and hepatocellular carcinoma in Korea. After hepatitis B vaccine era, seroprevalence of hepatits B surface antigen is decreasing, particularly in children. Hepatitis B vaccine is remarkably safe and shows high immunogenicity. Universal childhood immunization with three doses of hepatitis B vaccine in the first year of life is a highly effective method for prevention and control of hepatitis B.     

Incidence and routes of transmission of hepatitis B virus in England and Wales, 1995-2000: implications for immunisation policy.

BACKGROUND: The incidence of hepatitis B virus (HBV) infection in the UK is low. Since the infection can have serious sequelae, there is a continuing need to examine its epidemiology so as to inform control measures. OBJECTIVES: We aimed to describe the current HBV incidence and patterns of transmission in the UK, to estimate the rate of new carrier infections, and to discuss implications for the control of HBV through immunisation. STUDY DESIGN: We analysed routine England and Wales laboratory surveillance data of acute HBV infection (1995-2000) and data on migration and global HBsAg prevalence. RESULTS: The estimated annual incidence of HBV infection in England and Wales was 7.4 per 100,000. Injecting drug use was the most frequently reported route of transmission. The number of cases attributed to heterosexual contact was fairly stable, whereas the number of cases in men having sex with men decreased. These observations continue trends reported for the early 1990s. Transmission during childhood was rarely reported, but was more frequent among South Asians. The incidence in South Asians is relatively high, and their main risk factors are medical treatment overseas and heterosexual contact. For about a third of cases of acute HBV infection no route of transmission is reported, but analysis of secular trends and age distribution suggest that many of these may be related to injecting drug use. Endemic transmission gives rise to only a small proportion of all new chronic infections, with the vast majority arising from immigration of established HBV carriers. CONCLUSIONS: The incidence of acute HBV infection in England and Wales has remained low, with a similar pattern of reported routes of transmission compared to the early 1990s. The UK prevalence of HBV infection is dependant on global rather than national immunisation policy. Endemic transmission may be reduced by improving immunisation coverage among injecting drug users, which is expected to also reduce the number of cases without a risk factor reported. In addition, immunisation options that better suit the needs of ethnic minorities need to be explored.     

Hepatitis B virus: From diagnosis to treatment

During the next few decades, vaccination against hepatitis B virus (HBV) will dramatically change the epidemiological profile of this worldwide infection especially when Heath Policies encourage including HBV vaccination program for the newborns. However, it is still estimated that more than 2000 millions living people have met HBV. Symptomatic hepatitis with jaundice is less frequent than asymptomatic infection; however, as much as 350 millions of individuals remain chronically infected by HBV. In these cases, the need for efficient antiviral therapy remains clear when a viral replication is observed to control the risk of progression and the need for liver transplantation, which represents the only end-stage treatment. Indeed, patients having chronic hepatitis B (CHB) can now be successfully treated using nucleos(t)ide analogs (NA) or pegylated interferon (PEG-IFN). Therefore, beside vaccination, prevention of the progression of the disease to cirrhosis and liver decompensation, leading to end-stage liver disease and/or to hepatocellular carcinoma, by inhibiting viral replication seems to represent the best approach to improve survival. At last but not least, co-morbidities and other viral infections, leading also to chronic liver cirrhosis or liver inflammation such as the specific satellite delta virus (HDV), human immunodeficency virus (HIV) and/or hepatitis C (HCV) virus, are able to accelerate the progression and have to be taken in account. Interestingly, in treated infection, the dogma of the irreversibility of the liver fibrosis, when the cirrhosis is constituted, is tumbling down. In this review, we will focus on the clinical, virological and therapeutic aspects of hepatitis B infection in order to expose the proposals to follow-up and treat HBV-infected patients and the prevention of drug-resistant HBV mutants that frequently arise, leading to treatment failure and progression to liver disease.     

HBV疫苗接种后高、低、无应答个体B细胞特征的研究进展

乙型肝炎病毒(hepatitis B virus,HBV)感染一直以来都是世界范围内严重的公共卫生问题,可导致急、慢性肝脏疾病以及多种并发症。接种HBV疫苗诱导机体B细胞分泌保护性的乙型肝炎病毒表面抗体(hepatitis B surface antibody,HBsAb)是预防HBV感染最重要的措施。研究表明不同个体对HBV疫苗应答的效应不一致,可分为超高/高、正常/中等、低/无应答,对其产生机制的研究可为高滴度HBsAb制备、HBV感染防治等提供参考。本文将对HBV疫苗接种后不同应答效应个体B细胞特征和机制的研究概况与进展进行综述。     

Vaccination against viral hepatitis of HIV-1 infected patients

Reciprocal interactions between HIV and HAV or HBV can increase risk of morbidity and mortality in HIV disease and/or worsened the natural course of the hepatitis viruses. Hepatitis A vaccination is recommended for HIV infected patients at risk for exposure or severe disease: men who have sex with men, injecting drug users, patients with chronic liver disease and patients traveling in high endemic countries. As for healthy adults the scheme of vaccination is two doses 6 or 12 mo apart, nevertheless, seroconversion rates are lower. A third dose could improve the seroconversion rates. Hepatitis B vaccination is recommended for all HIV infected persons lacking prior immunity. As the immune response to hepatitis B vaccines is impaired in HIV-infected adults, four double doses of hepatitis B vaccine could enhance serological response. To assume a higher immune response, vaccines should be administered in HIV-infected patients with undetectable HIV viral load and high CD4 cell count.     

西藏墨脱县1262名中小学生乙肝标志物检测结果分析

目的了解墨脱县1262名中小学生乙型肝炎病毒（HBV）感染状况,为乙肝防治工作的开展提供依据。方法用酶联免疫方法检测HBsAg、抗-HBs、HBeAg、抗-HBe和抗-HBc五项乙肝标志物,Excel统计软件对检测结果进行统计分析。结果1262名中小学生乙肝标志物五项全阴者有886人,占70.2%;仅有303名中小学生有保护性的乙肝表面抗体,占24.0%;39名学生HBsAg阳性,阳性率3.1%。HBsAg阳性39名学生中,HBsAg、HBeAg和抗-HBc三项阳性的学生有27名,占69.2%。结论1262名中小学生中乙肝标志物五项全阴者比例较高,有保护性抗体的比例较低,存在接触感染乙肝病毒的较大风险,因此,加强西藏墨脱县中小学生乙肝疫苗接种工作刻不容缓。     

TT病毒在谷丙转氨酶升高的体检者和肝病患者中检 …

目的 通过研究ＴＴ病毒在谷丙转氨酶升高的体检人群和肝病患者中的意义。探讨其致病性。方法 收集１９例谷丙转氨酶升高体验者和４１例转氨酶正常的随机对照的血清,以及１８２例肝病患者的血清,采用ＰＣＲ方法检测ＴＴ病毒的ＤＮＡ。聚合酶链反应（ＰＣＲ）产物经限制性片段长度多态性（ＲＦＬＰ）分析验证。同时检测甲,乙,丙,戊,庚型肝炎病毒（ＨＡＶ,ＨＢＶ,ＨＣＶ和ＨＧＶ）感染标志。结果 １９例转氨酶升高体检者中,     

Hepatitis B vaccination in children: The Taiwan experience

The world's first nationwide hepatitis B virus (HBV) universal vaccination program for infants was launched in Taiwan in July, 1984. All infants received three to four doses plasma or recombinant HBV vaccines. In addition, infants of HBeAg-positive mothers received 0.5 ml of hepatitis B immunoglobulin within 24 hours after birth. The vaccination coverage rate is as high as 97%. Seroprevalence of hepatitis B surface antigen (HBsAg) declined from 9.8% (prevaccination period) to 0.6% in children in Taipei City after 20 years of mass vaccination. The seropositive rates for HBsAg, antibody to HBsAg, and antibody to hepatitis B core antigen were 1.2%, 50.5%, and 3.7%, respectively, in those born after the vaccination program (< 20 years old) in 2004. In line with the decrease of chronic HBV infection, the incidence of hepatocellular carcinoma (HCC) also decreased in children in Taiwan. From 1981 to 1994, the incidence of HCC in 6- to 9-year-olds declined from 0.52/100,000 for those born between 1974 and 1984 to 0.13 for those born between 1984 and 1986 (p < 0.001). We extended the observation to 2000, the incidence of HCC per 100,000 children declined from 0.54 to 0.20. The prevalence of a determinant mutants (amino acids 121–149 of HBsAg) in Taiwanese carrier children was 7.8% (eight out of 103) in 1984, increased to 19.6% (10 out of 51) in 1989, peaked at 28.1% (nince out of 32) in 1994, and remained stationary at 23.1% (three out of 13) and about 25% in 1999 and 2004, respectively; it was higher in those fully vaccinated compared with those not vaccinated. The other group of subjects who are susceptible to vaccine failure is the immunocompromized hosts. We observed some de novo HBV infection in children after liver transplantation. Despite of the success of hepatitis B immunization, childhood chronic HBV infection and HCC were not eliminated by the universal vaccination program. Among those HBsAg carriers born after the vaccination program, 89% of their mothers were found to be positive for HBsAg, indicating the importance of maternal transmission. This was also true in the mothers of children with HCC, of them 96% were HBsAg positive. After two decades of universal infant HBV vaccination, we found this program provides long-term protection for up to more than 20 years, and a universal booster is not required for the primary HBV vaccinees before adulthood. Mother-to-child transmission, although largely diminished, is still the main cause for immunoprophylaxis failure. The emergence of escape mutant did not impose increased risk of chronic infection at present. Nevertheless, development of new vaccines may overcome the vaccine failure.     

HBV mutations and their clinical significance

PURPOSE: The launch of the vaccine against HBV in 1983 significantly reduced the number of HBV infections in the world. But there still remain a large group of people with chronic hepatitis B who were infected before beginning of vaccination programs or in whom the vaccine was - for various reasons - ineffective. Current therapy of HBV infection based on PEG-IFN α-2a or nucleotide/nucleoside analogues does not guarantee sustained virologic response in the large majority of chronically infected persons. Treatment with some nucleoside analogues is associated with mutations and subsequent selection of resistant strains resulting with therapeutic failure, risk of cross-resistance to other drugs and finally selection of mutants with oncogenic properties.     

Enhanced surveillance for childhood hepatitis B virus infection in Canada, 1999-2003

Since hepatitis B virus (HBV) infection can have serious sequelae, especially if infection occurs during childhood, there is a continuing need to examine its epidemiology so as to inform control measures. We analyzed trends in disease incidence and patterns of hepatitis B virus (HBV) transmission in both Canadian-born and non-Canadian-born children from 1999 to 2003, through the Enhanced Hepatitis Strain Surveillance System. Amongst Canadian-born children, the incidence of newly identified HBV infection per 100,000 declined significantly during the study period from 1.4 in 1999, to 0.5 in 2003 (RR, 0.75 per year; 95% CI, 0.60-0.95). Amongst non-Canadian-born children, the incidence of HBV infection per 100,000 ranged from 9.4 to 16.3, during the study period (linear trend test, p=0.69). Poisson regression analysis revealed that non-Canadian-born children were more likely to have HBV infection (RR, 12.3; 95% CI, 7.6 to 19.8), than Canadian-born children. HBV infection was found to be more common among children emigrating from high endemic area, than among Canadian-born children. Current Canadian immunization policy should take into consideration the protection of all children against HBV infection, including those coming from countries where mass hepatitis B vaccination programs have still not been launched.     

Epidemiological study of hepatitis B virus infection in Manitoba, Canada, 1992–2003

In comparison with other Canadian provinces and most Western countries, the province of Manitoba maintains a different vaccination policy for hepatitis B. This policy provides selective antenatal screening for hepatitis B in women and an inoculation program for hepatitis B vaccination for fourth-grade pupils. There has been increasing concern for this policy with regard to its influence on secular trends of acute hepatitis B incidence in Manitoba. This created a need to summarise the epidemiological characteristics of hepatitis B virus (HBV) infection in Manitoba and to allocate finances and human resources for future prevention programs. The Cadham Provincial Laboratory in Winnipeg, a Canadian Public Health Laboratory, is responsible for testing all specimens for diagnosis of various common infectious diseases in Manitoba. During the period from 1 January 1992 to 31 December 2003, a total of 285,946 clinical specimens were submitted to this laboratory, which confirmed 310 cases of acute HBV and 7,556 cases of chronic HBV infection. A total of 18,168 individuals were identified as having vaccine-induced immune status. The incidence rate of acute HBV infection has significantly decreased from 6.52/100,000 person-years in 1996 to 0.86/100,000 person-years in 2003. Annual prevalence rates of chronic HBV infection in Manitoba increased slightly from 42.96 cases/100,000 population in 1992 to 71.47 cases/100,000 population in 2003. Incidence rates were generally higher in men than in women at all age groups, with values of 2.65 and 1.65 per 100,000 population, respectively (chi-square=15.768, p value <0.001). The highest incidence rate for both males and females was observed in the age group 30–34 years. The North Eastman and Winnipeg Regional Health Authorities showed significantly higher incidence rates of acute hepatitis B compared with the other nine Regional Health Authorities. Selective hepatitis B vaccination programs for children in Manitoba had achieved the greatest success in the prevention of vertical and horizontal transmission. There is an urgent need to develop cost-effective harm-reduction strategies for hepatitis B prevention among adults (aged 30–34) and groups at risk in Manitoba.     

吸毒人群丙型和乙型肝炎病毒感染的血清流行病学研究

目的　调查广州市吸毒人群丙型肝炎病毒（ＨＣＶ） 和乙型肝炎病毒（ＨＢＶ） 的感染状况。方法　在广州市两所戒毒所４８３ 名男性吸毒人员中，用酶标记免疫（ＥＬＩＳＡ） 法，调查ＨＢＶ、ＨＣＶ感染情况，并以正常人群作对照组观察。结果　广州市吸毒人群中，ＨＣＶ、ＨＢＶ的感染率及这两种病毒的混合感染率，分别为６７－４９％ 、９０－４８ ％ 、６２－７３％ ，明显高于正常人群对照组的３－７５％ 、５５－６３ ％ 、３－７５％ 。结论　静脉吸毒是ＨＢＶ、ＨＣＶ感染的主要危险因素。广州市吸毒人群当中，存在着极高的丙型肝炎病毒和乙型肝炎病毒感染率     

Hepatitis B and blood transfusion

Hepatitis B is caused by infection with pandemic hepatitis B virus (HBV) and has a serious impact on blood safety worldwide. Active immunization is an efficient preventive measure particularly in countries with medium and high HBV prevalence. However, as long as only some countries have started immunization programmes for their younger population and escape mutants occur, stringent donor selection and testing is presently the only approach to reduce the risk of transfusion transmitted HBV infections. Surrogate testing for alanine aminotransferase (ALT) has shown its limitations and has mostly been discontinued especially since sensitivity and specificity of hepatitis B surface antigen (HBsAg) tests have been continuously improved. However, there remains a significant risk by donations from freshly infected donors who have not yet developed detectable HBsAg levels and donations by donors with occult infection that are HBsAg‐negative but HBV DNA‐positive. Nucleic acids amplification technology (NAT) has been applied primarily to close the diagnostic window between HBV infection and HBsAg detection and has shown to be effective either in testing donor samples in mini‐pools or by individual donation (ID) testing. It has also been shown that mini‐pool NAT may not be sufficiently sensitive to identify occult chronic carriers who show very low virus concentrations in their plasma. For those chronically infected donors, highly sensitive mini‐pool NAT with specific enrichment procedures and ID NAT may be required. Anti‐HBc testing would be the most sensitive approach resulting in highest yield rates for occult carriers. However, for medium and high prevalence countries, deferral rates would be extremely high with negative effects on the blood supply. Inactivation would be a reasonable alternative but at very high costs and is presently not applicable to all blood components. Future scenarios will most probably be diverse, depending on the prevalence in a given country, its resources and the vaccination status of its population.     

Age- and sex-related study of hepatitis B virus chronic carrier state in infants from an endemic area (Senegal)

This report concerns hepatitis B virus (HBV) infections observed in 155 infants from Senegal, studied with a view to determining the factors involved in development of the chronic carrier state. A chronic carrier state was observed in 50.3% of the infants. This study confirms that the risk of chronic carriage is linked to age. This risk declines very rapidly with age, falling from 82% in infants under 6 months old, to 15% in children between the ages of 2 and 3 years. Spontaneous elimination of hepatitis B surface antigen (HBsAg) is uncommon in HBsAg carriers during childhood. The difference observed in chronic carriage between males and females is due to a difference in susceptibility of the two sexes to the development of the chronic carrier state: HBV infections (before 2 years of age) lead to a chronic carriage in 77% of males as against 50% of females. These conclusions are important in view of the immunisation programs being carried out against hepatitis B virus in endemic areas. For a maximum efficacy, vaccination must be carried out at birth, or shortly afterwards.     

Risk and management of blood-borne infections in health care workers

Exposure to blood-borne pathogens poses a serious risk to health care workers (HCWs). We review the risk and management of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infections in HCWs and also discuss current methods for preventing exposures and recommendations for postexposure prophylaxis. In the health care setting, blood-borne pathogen transmission occurs predominantly by percutaneous or mucosal exposure of workers to the blood or body fluids of infected patients. Prospective studies of HCWs have estimated that the average risk for HIV transmission after a percutaneous exposure is approximately 0.3%, the risk of HBV transmission is 6 to 30%, and the risk of HCV transmission is approximately 1.8%. To minimize the risk of blood-borne pathogen transmission from HCWs to patients, all HCWs should adhere to standard precautions, including the appropriate use of hand washing, protective barriers, and care in the use and disposal of needles and other sharp instruments. Employers should have in place a system that includes written protocols for prompt reporting, evaluation, counseling, treatment, and follow-up of occupational exposures that may place a worker at risk of blood-borne pathogen infection. A sustained commitment to the occupational health of all HCWs will ensure maximum protection for HCWs and patients and the availability of optimal medical care for all who need it.     

2005年河南省漯河市三县区农村居民乙肝感染状况调查分析

目的 了解漯河市农村居民乙肝感染现状。方法 按照分散选点，整群随机抽样的原则采血8862人，用ELISA法进行ALT、HBsAg、抗．HBs、HBeAg、抗-HBe、抗-HBc检测。结果 乙肝病毒总感染率为51．33％，HBsAg阳性率为4．33％，抗．HBs阳性率为49．77％，抗-HBc阳性率33．44％。结论 乙肝表面抗原阳性率明显低于全国水平，易感人群较多，加强新生儿乙肝疫苗首针及时率，提高整体人群免疫率，是今后乙肝防制的重点。