The importance of imported infections in maintaining hepatitis B in The Netherlands

In The Netherlands, in May 1999 an enhanced surveillance of hepatitis B was begun to collect detailed information of patients with acute hepatitis B virus (HBV) infection. The objective was to gain insight in transmission routes and source of infection of new HBV cases. Through public health services, patients were interviewed on risk factors. It appeared that the majority (59%) acquired the infection through sexual contact; 52% of these by homosexual and 48% by heterosexual contact. In 60% of the heterosexual cases, the source of infection was a partner originating from a hepatitis B-endemic region. Sexual transmission is the most common route of transmission of acute hepatitis B in The Netherlands and introduction of infections from abroad plays a key role in the current epidemiology of HBV. As well as prevention programmes targeted at sexual high-risk groups, prevention efforts should focus more on the heterosexual transmission from HBV carriers.     

HIV and hepatitis B infection and risk behavior in young gay and bisexual men.

OBJECTIVES: To estimate the prevalence of and identify risk factors for human immunodeficiency virus type 1 (HIV-1) and hepatitis B virus (HBV) infections and unprotected anal intercourse among young homosexual and bisexual men. METHODS: The authors performed a cross-sectional analysis of data from a prospective cohort of 508 young gay and bisexual men ages 18-29. RESULTS: HIV-1 seroprevalence was 2.4%, with five (1.3%) of 390 college students and seven (6.0%) of 117 non-students infected. After adjusting for confounders, HIV-1 infection was associated with having a history of a sexually transmitted disease other than HIV-1 or hepatitis B. The prevalence of hepatitis B markers in unvaccinated men was 12.9%. The presence of hepatitis B markers in unvaccinated men was significantly associated with Asian ethnicity, off-campus residence, and history of a sexually transmitted disease other than HIV-1 or hepatitis B and inversely associated with recent non-intravenous drug use. Eighteen percent of the participants reported having had sex with women during the previous 12 months, and 26.4% reported a history of unprotected anal intercourse during the previous six months. Men who reported unprotected anal intercourse were more likely to have at least one steady partner, to have met their partners in anonymous settings, and to be identified as probably alcohol dependent. CONCLUSIONS: Although the prevalence of HIV-1 infection among young homosexual and bisexual men in Boston was relatively low, the high rates of unprotected anal intercourse suggest a potential for future HIV-1 and hepatitis B transmission. Interventions should focus on young men with histories of sexually transmitted diseases, alcohol abuse, and depression.     

Phylogenetic analysis of isolates from new cases of HBV infection in Southern Italy

The level of endemicity of hepatitis B virus (HBV) infections in Italy is low and genotype D infections predominant. New HBV strains may however be introduced as a result of movements of people from regions of high endemicity. The aim of the present study was to determine whether strains from new cases of acute hepatitis B detected in southern Italy were due to endemic or new HBV strains. We studied 34 isolates from patients with acute hepatitis B infection, and 35 from chronic hepatitis B patients. A phylogenetic analysis of preS/S region was done by comparing the sequences from the acute and chronic cases with references sequences. The study showed that 44% of strain from acute hepatitis B patients were of genotype A, 53% of genotype D, and 3% of genotype E. The molecular analysis of isolates from acute hepatitis B patients from Sicily showed a change in the local epidemiology of this infection, with an increase in HBV/A infections and a clustering effect for HBV D2, possibly correlated to immigration. The introduction of new genotypes , could have an effect on HBV-correlated diseases due to the different association between genotype, liver disease and response to antiviral therapy.     

Transmission of hepatitis B virus by a surgeon

A Dutch surgeon transmitted hepatitis B virus (HBV) to several of his patients (8 certain cases, 2 probable cases and 18 possible cases). To view this accident in the proper context, we estimated the incidence of HBV transmission in the Netherlands from surgeons to patients (1/37,000 surgical procedures) and from patients to non-immune surgeons (0.8%/surgeon/year). The incident as such is alarming because of the high frequency of HBV transmission that occurred. However, the number of infections involved was lower than the expected number of iatrogenic HBV infections in the Netherlands during the given period. It is advisable to quickly implement the WHO guidelines, demanding universal HBV vaccination of infants, and to organize vaccination of risk groups (including medical personnel) in the Netherlands.     

Acute hepatitis B in Edinburgh 1975-92: a retrospective study in a population where human immunodeficiency virus is highly prevalent.

A retrospective study of notified hepatitis B virus (HBV) infection in Edinburgh during 1975-92 identified 525 acute cases. For 343 where a probable transmission route could be determined, 215 were due to shared equipment by injection drug users (IDUs), 29 to homosexual intercourse, 25 to heterosexual or household contact with IDUs, 21 to heterosexual contact with infected non-IDU partners and 53 to various other or multiple routes. Cases were unevenly distributed geographically, particularly those among IDUs. The highest incidence within a post code district was approximately 2.5 times that for all Edinburgh. Annual cases peaked in 1984 then declined to low levels in the early 1990s. This reduction was most marked among IDUs, and may be ascribed both to changed injecting behaviour and decreased susceptibility within this group. The latter factor implies that HBV infections may be an unreliable guide to human immunodeficiency virus (HIV) infection in populations where HBV is highly prevalent.     

Incidence of acute hepatitis B--United States, 1990-2002

Hepatitis B virus (HBV) is a bloodborne and sexually transmitted virus that is acquired by percutaneous and mucosal exposure to blood or other body fluids of an infected person. Clinical manifestations of acute hepatitis B can be severe, and serious complications (i.e., cirrhosis and liver cancer) are more likely to develop in chronically infected persons. In the United States, approximately 1.2 million persons have chronic hepatitis B virus (HBV) infection and are sources for HBV transmission to others. However, since the late 1980s, the incidence of acute hepatitis B has declined steadily, especially among vaccinated children. To characterize the epidemiology of acute hepatitis B in the United States, CDC analyzed national notifiable disease surveillance data for 1990-2002. This report summarizes the results of that analysis, which indicated that, during 1990-2002, the incidence of reported acute hepatitis B declined 67%. This decline was greatest among children and adolescents, indicating the effect of routine childhood vaccination. The decline was lowest among adults, who accounted for the majority of cases; incidence increased among adults in some age groups. To reduce HBV transmission further in the United States, hepatitis B vaccination programs are needed that target men who have sex with men (MSM), injection-drug users (IDUs), and other adults at high risk.     

Vaccination against hepatitis B in low endemic countries

A mathematical model that takes transmission by sexual contact and vertical transmission into account was employed to describe the transmission dynamics of hepatitis B virus (HBV) and vaccination against it. The model is an extension of a model by Williams et al. (Epidemiol Infect 1996: 116; 71-89) in that it takes immigration of hepatitis B carriers from countries with higher prevalence into account. Model parameters were estimated from data from The Netherlands where available. The main results were that, given the estimates for the parameters describing sexual behaviour in The Netherlands, the basic reproduction number R0 is smaller than 1 in the heterosexual population. As a consequence, the immigration of carriers into the population largely determines the prevalence of HBV carriage and therefore limits the possible success of universal vaccination. Taking into account the prevalence of hepatitis B carriage among immigrants and an age-dependent probability of becoming a carrier after infection, we estimate that a fraction of between 5 and 10% of carrier states could be prevented by universal vaccination.     

Hepatitis B infection in households of acute cases.

Seroepidemiological studies conducted in 369 household contacts of 80 acute cases of hepatitis B in Singapore showed that asymptomatic chronic carriers of hepatitis B surface antigen (HBs Ag) are the main source of acute hepatitis B infection. The HBs Ag prevalence rate in asymptomatic household members was 20% compared with a 6% prevalence for the general population. The majority of the household carriers (60%) were highly infectious with positive hepatitis e antigen (HBe Ag). The overall prevalence of HBV infection (with at least one HBV marker) of the household contacts was 40.7%. Spouses and parents of acute cases had a significantly higher prevalence of HBV infection than other members of the families. HBV prevalence rate showed no association with the household size. Factors associated with the risk of transmission of HBV infection included sharing of various personal and household articles, such as toothbrush, towel, handkerchief, clothing, razor, comb, bed and bedding. Sleeping in the same bedroom, eating together at meals, and sharing of eating and drinking utensils were not associated with an increased risk of transmission of infection. Follow-up studies six months later showed that 30% of the acute cases became chronic HBs Ag carriers (with 46% HBe Ag positive), thus providing an additional source of infection in the families, while 8% of the susceptible household members acquired asymptomatic HBV infection. Health education on the prevention of HBV transmission in the homes of acute cases should be based on sound epidemiological information. Household contacts of acute cases of hepatitis B should be routinely screened and the susceptible vaccinated against the disease as soon as possible.     

Multiple outbreaks of hepatitis B virus infection related to assisted monitoring of blood glucose among residents of assisted living facilities--Virginia, 2009-2011

Between February 2009 and November 2011, the Virginia Department of Health (VDH) was notified of acute hepatitis B virus (HBV) infections occurring in residents of four separate assisted living facilities (ALFs) in the Central Health Planning Region of Virginia. In each outbreak, the initial acute HBV infections were identified through routine viral hepatitis surveillance. VDH conducted epidemiologic and laboratory investigations of these reports. Infection control practices, particularly surrounding assisted monitoring of blood glucose (AMBG), were assessed by direct observation and staff member interviews. Further investigation and subsequent screening of ALF residents for hepatitis B uncovered additional acute HBV infections at each of the ALFs. ALF residents screened for HBV infection were categorized on the basis of published criteria as having acute or chronic infection, or being susceptible or immune to infection. All acute HBV infections were among residents receiving AMBG for management of diabetes. AMBG is safe when properly performed, but lapses in infection prevention practices during AMBG were identified at three of the four facilities. These outbreaks highlight the role of hepatitis B surveillance in detecting disease outbreaks and the need for a comprehensive strategy to prevent HBV transmission in ALFs, including vaccination, improved infection control oversight at ALFs, appropriate training of staff members performing AMBG, and prompt investigation of acute HBV infections.     

Six years of sentinel surveillance of hepatitis B in general practice in France

Despite the availability of a safe and efficacious vaccine, new cases of infection by hepatitis B virus (HBV) still occur at a substantial rate. This increases the current prevalence of chronic HBV carriers (10% of newly infected subjects) and in the long run, will raise the incidence of chronic liver disease. The surveillance of viral hepatitis commenced in December 1990 by the French sentinel network for electronic surveillance of communicable diseases. Between 1991 and 1996, a decrease in the annual incidence was observed although it was not significant (p=0.06). The mean number of cases for this period was 12 per 100,000 inhabitants. The sex ratio (M/F) was 1.6 (p<0.01) and the median age, 32 years. Heterosexual transmission was suspected in 25% of cases, homo- bisexual transmission in 10%, use of injected drugs in 19%, percutaneous exposure in 9%, and blood transfusion or hemodialysis in 6%. Although the incidence of HBV infection is decreasing, the prevalence of chronic infection will continue to rise. However, the universal hepatitis B immunisation strategy proposed by WHO will dramatically limit the expansion of the population of chronically infected subjects if high coverage is achieved rapidly.     

Sexual transmission of hepatitis C virus infection

The role of sexual transmission in the diffusion of HCV infection, was studied through the seroprevalence of anti-HCV antibodies in the heterosexual habitual partners of 83 anti-HCV positive subjects. The index cases were represented by 10 dialysed subjects, 31 patients with chronic liver disease and 42 healthy carriers. Seroprevalence of anti-HCV positivity reported in partners was 8.43%, with a higher rate in cohabitants of patients with chronic liver disease (16.12% vs 4.76% of carriers); no case was found among partners of dialysed subjects. Laboratory and ultrasonograph signs of chronic hepatitis were reported in 3 cases (3.61%). Control on 70% of the cohabitants' relatives, was negative for HCV infections. These data suggest a possible sexual transmission of HCV infection, even if its prevalence resulted modest, undoubtedly lower than in other disease sexually transmitted.     

乙型肝炎病毒宫内传播机制研究进展

慢性乙型肝炎病毒(hepatitis B virus,HBV)感染者中母婴传播占50％以上,围生期HBV感染者90％以上会发展为慢性携带者,且有较高肝硬化和(或)肝癌的发生风险.宫内感染是乙型肝炎疫苗+乙型肝炎免疫球蛋白联合免疫失败致HBV母婴传播的主要原因.HBV宫内感染途径有生殖细胞感染、经胎盘屏障渗漏、经胎盘细胞...     

Hepatitis B vaccination of inmates in correctional facilities--Texas, 2000-2002

In December 2002, approximately 2.2 million persons were incarcerated in the United States; an estimated 8 million were released to the community that year. In 2001, approximately 22,000 acute hepatitis B cases and 78,000 new hepatitis B virus (HBV) infections occurred in the United States (3); an estimated 29% of these cases were in persons who had been incarcerated previously. The majority of HBV infections among incarcerated persons are acquired in the community; however, infection also is transmitted within correctional settings. Hepatitis B vaccination of incarcerated persons is recommended to prevent transmission in correctional facilities and in previously incarcerated persons on their return to the community. In May 2000, the Texas Department of Criminal Justice (TDCJ), which oversees custody of state jail and prison inmates, implemented a hepatitis B vaccination program. To determine hepatitis B vaccination rates of inmates during 2000-2002, TDCJ reviewed charts of inmates released during a 3-day period for documentation of vaccination. This report summarizes the results of that study, which indicated that rates of vaccine acceptance and vaccine series completion among inmates were high. Establishing hepatitis B vaccination programs in prisons and jails can prevent a substantial proportion of HBV infections among adults in the outside community.     

Transmission of hepatitis B virus in correctional facilities--Georgia, January 1999-June 2002

Incarcerated persons have a disproportionate burden of infectious diseases, including hepatitis B virus (HBV) infection. Among U.S. adult prison inmates, the overall prevalence of current or previous HBV infection ranges from 13% to 47%. The prevalence of chronic HBV infection among inmates is approximately 1.0%-3.7%, two to six times the prevalence among adults in the general U.S. population. Incarcerated persons can acquire HBV infection in the community or in correctional settings. This report summarizes the results of 1) an analysis of hepatitis B cases among Georgia inmates reported to the Georgia Department of Human Resources, Division of Public Health (DPH) during January 1999-June 2002, including a retrospective investigation of cases reported during January 2001-June 2002; and 2) a prevalence survey conducted in prison intake centers during February-March 2003. These efforts identified cases of acute hepatitis B in multiple Georgia prisons and documented evidence of ongoing transmission of HBV in the state correctional system. The findings underscore the need for hepatitis B vaccination programs in correctional facilities.     

Acute hepatitis B infection in England and Wales: 1985-96

Confirmed acute hepatitis B infections are reported to the Public Health Laboratory Service Communicable Disease Surveillance Centre by laboratories in England and Wales. These reports have been used to monitor trends in the incidence of hepatitis B virus (HBV) infection over time, and between exposure categories and age groups. Between 1985 and 1996 a total of 9252 cases of acute HBV infection were reported; the number of reports fell from 1761 in 1985 to 581 in 1996. Most infections were reported in adults aged 15-44 years [n = 7365 (80%)], and infections were more commonly reported in males [n = 6490 (70%)] than females [n = 2658 (29%)]. The probable means of acquisition was known for just over half of all adult cases [4827/8956 (54%)]. Injecting drug use was the most common exposure [n = 1901 (21%)], followed by sex between men and women [n = 1140 (13%)] and sex between men [n = 1025 (11%)]. The number of infections in injecting drug users fell in the late 1980s, but increased again from 1991 onwards. In children aged under 15 years, infections acquired by mother to baby transmission accounted for 35/170 (21%) of the total. Surveillance indicates that the incidence of acute hepatitis B infection fell in the late 1980s, probably reflecting changed behaviour in injecting drug users. An increase in the number of infections in injecting drug users since 1993 may indicate ongoing transmission that has not been contained by the introduction of needle exchange schemes or by selective vaccination.     

Prevalence of hepatitis B virus infection in The Netherlands in 1996 and 2007

We aimed to assess differences in the prevalence of hepatitis B virus (HBV) infection in The Netherlands between 1996 and 2007, and to identify risk factors for HBV infection in 2007. Representative samples of the Dutch population in 1996 and 2007 were tested for antibodies to hepatitis B core antigen (anti-HBc), hepatitis B surface antigen (HBsAg) and HBV-DNA. In 2007, the weighted anti-HBc prevalence was 3·5% (95% CI 2·2-5·5) and the HBsAg prevalence was 0·2% (95% CI 0·1-0·4). In indigenous Dutch participants, the anti-HBc prevalence was lower in 2007 than in 1996 (P=0·06). First-generation migrants (FGMs) had a 13-fold greater risk of being HBsAg- and/or HBV-DNA-positive than indigenous Dutch participants. In indigenous Dutch participants, risk factors for anti-HBc positivity were older age and having received a blood product before 1990. In FGMs, being of Asian origin was a risk factor. In second-generation migrants, having a foreign-born partner and injecting drug use were risk factors. FGMs are the main target group for secondary HBV prevention in The Netherlands.     

Hepatitis B Virus Infection: Epidemiology and Vaccination

Worldwide, two billion people have been infected with hepatitisB virus (HBV), 360 million have chronic infection, and 600,000die each year from HBV-related liver disease or hepatocellularcarcinoma. This comprehensive review of hepatitis B epidemiologyand vaccines focuses on definitive and influential studies andhighlights current trends, policies, and directions. HBV canbe transmitted vertically, through sexual or household contact,or by unsafe injections, but chronic infections acquired duringinfancy or childhood account for a disproportionately largeshare of worldwide morbidity and mortality. Vaccination againstHBV infection can be started at birth and provides long-termprotection against infection in more than 90% of healthy people.In the 1990s, many industrialized countries and a few less-developedcountries implemented universal hepatitis B immunization andexperienced measurable reductions in HBV-related disease. Forexample, in Taiwan, the prevalence of chronic infection in childrendeclined by more than 90%. Many resource-poor nations have recentlyinitiated universal hepatitis B immunization programs with assistancefrom the Global Alliance for Vaccines and Immunization. Furtherprogress towards the elimination of HBV transmission will requiresustainable vaccination programs with improved vaccination coverage,practical methods of measuring the impact of vaccination programs,and targeted vaccination efforts for communities at high riskof infection. hepatitis B • hepatitis B vaccines • hepatitis B virus • immunization programs     

A mathematical model of hepatitis B virus transmission and its application for vaccination strategy in china

BACKGROUND: Before universal infant immunization against hepatitis B virus (HBV) in 1986 China was a region endemic for HBV infection. The prevalence of HBV infection in the population was about 60% and the proportion of chronic HBV carriers around 10%. These HBV carriers could progress to chronic hepatitis B, cirrhosis, and primary hepatocellular carcinoma. Since 1976, large-scale sero-surveys of HBV infection have been carried out and a lot of data have been collected. METHOD: This paper describes a mathematical model developed to predict the dynamics of HBV transmission and to evaluate the long-term effectiveness of the vaccination programme. We used a compartment model expressed by a set of partial differential equations based on the characteristics of HBV infection. RESULTS: All parameters, expressed in the model as a non-linear function of age and time since vaccination, were estimated using sero-survey data. The model fits well with both pre-vaccination and post-vaccination sero-surveys. The observed and estimated age-specific prevalence rates of HBV infection and HBV carriage agree with each other. According to our model, if all newborns are vaccinated according to schedule, the rate of HBV carriage will decline sharply over time to 0.2% in 70 years. By then, the ratio of acute hepatitis B will be less than 0.5% and the ratio of chronic hepatitis B will be around 5%. CONCLUSIONS: The results suggest that HBV infection in China can be controlled in just one generation, and eventually eliminated. Our model shows that vaccination coverage is the most important indicator for the elimination of HBV transmission. The higher the vaccination coverage, the better the long-term effectiveness of immunization. Thus, the key to controlling and eliminating HBV transmission in China is to find ways to immunize all infants throughout the country, especially in poor, rural areas.     

Preventing transmission of hepatitis B virus from people with chronic infection

BACKGROUND: People with chronic hepatitis B virus (HBV) infection are the major source of HBV transmission in the United States. The Public Health Service recommends prevention counseling for HBV-infected people and vaccination of their household contacts and sexual partners. OBJECTIVES: To describe the implementation of these recommendations by community physicians. METHODS: Telephone survey of 69 people with chronic HBV infection and their healthcare providers, October 1997 through November 1997, in San Diego, California. MAIN OUTCOME MEASURES: Counseling of people with chronic HBV infection and vaccination of their household contacts and sexual partners. RESULTS: Forty-three percent of providers reported providing prevention counseling to their HBV-infected patients to reduce transmission; 16% of patients reported receiving counseling. For the 32 pairs for which both the patient and provider could be reached and the patients were aware of their HBV infection, 20 (63%) providers reported counseling patients, and 10 (50%) of these providers' patients reported receiving counseling. Fifty-five percent of providers recommended vaccination of contacts; 13% of eligible adult household contacts and sexual partners and 20% of eligible child household contacts had begun hepatitis B vaccination. CONCLUSIONS: Prevention counseling of people with chronic HBV infection and vaccination of their contacts occur infrequently despite guidelines and an effective vaccine. Collaborative efforts between providers and people involved in public health are needed to improve delivery of these preventive health services.     

Using automated extraction of hepatitis B tests for surveillance: evidence of decreasing incidence of acute hepatitis B in England

Surveillance of acute hepatitis B in England is necessary to estimate incidence, determine routes of transmission and inform public health actions. Here we describe an automated process to extract information on testing for markers of hepatitis B infection in English sentinel laboratories between 2002 and 2008. The resulting data were used to identify individuals with acute infections, describe their characteristics and estimate the incidence of infection. Two-thirds of acute infections were in males. Heterosexual exposure and injecting drug use were the main risks reported. Annual incidence was estimated at 1.3/100 000 person-years overall (1.7 and 0.6 for males and females, respectively) and declined each year. Automated extraction of hepatitis B markers, including quantitative results where available, can help to classify HBV status more accurately for surveillance. HBV incidence in England is at its lowest level in recent years.