Epidemiology and long-term consequences of hepatitis delta virus infection in the Yucpa Indians of Venezuela.

To define better the epidemiology and clinical impact of hepatitis delta virus (HDV) infection among hepatitis B virus (HBV) carriers in less developed countries, the authors prospectively studied a cohort of 216 Yucpa Indian HBV carriers in Venezuela. HBV carriers were followed regularly between 1983 and 1988 by physical examination, laboratory testing for liver enzymes and HBV and HDV markers, and epidemiologic history. Among the cohort, 74 (34%) were initially positive for HDV infection, and 35 additional persons became infected during the study. Risk factors for new HDV infection included living in southern Yucpa villages; being young adults (15-19 years) or young children (1-9 years), and living in a household with a person with acute HDV infection. Persons with HDV infection were at high risk of developing chronic liver disease; 56% of HDV-infected persons had moderate-to-severe chronic liver disease at the end of the study compared with none of the HBV carriers without HDV infection. Mortality rates were 6.9% and 8.8% per year, respectively, among initially HDV-positive HBV carriers and those with new HDV infection, because of rapidly progressive chronic liver disease and fulminant hepatitis; mortality was significantly lower in HBV carriers without HDV infection and in non-HBV carriers. HDV superinfection is a devastating disease in HBV carriers in tropical South America. Prevention of HBV infection with hepatitis B vaccine is the best available tool to reduce the impact of this problem.     

Hepatitis delta virus infection in Bombay.

From June 1985 to June 1989, sera from 425 cases of acute viral hepatitis were gathered from 2 hospitals in Bombay; 331 sera were positive for hepatitis B surface antigen and immunoglobulin M anti-hepatitis B core antigen, and the donors' disease was diagnosed as hepatitis B. Anti-hepatitis D virus was found in 124 of these sera, and hepatitis D antigen was present in 24 more, conclusively proving the presence of hepatitis delta infection in association with hepatitis B in Bombay. Among the 425 cases of hepatitis, 39 cases of fulminant hepatitis developed, of whom 31 died. Hepatitis B virus (HBV) was the apparent viral infection in 32 of the fulminant cases, and 20 (63%) of them also showed evidence of hepatitis D virus (HDV) infection, suggesting an aggravation of their clinical course due to concurrent HBV and HDV infections.     

Epidemiology and clinical outcome of hepatitis D virus infection in Turkey

The prevalence, the epidemiology, the clinical and biochemical characteristics of hepatitis delta virus (HDV) infection were studied in patients with HBsAg-positive acute hepatitis, in those with chronic liver disease, and in apparently healthy carriers in Turkey.Fifty-eight of the 242 carriers of HBsAg (23.9%) and 31 of the 237 (13.1%) patients with acute HBsAg-positive hepatitis had serological evidence of HDV infection. Eleven of these individuals were HBsAg carriers with acute HDV superinfection. The prevalence of HDV infection was significantly (p < 0.001) higher in patients with chronic liver disease (54/165; 32.7%) than in asymptomatic carriers of HBsAg (4/77; 5.2%). The highest prevalence (26/57; 45.6%) of HDV infection was found in patients at high risk of acquiring hepatitis virus infection (health care workers, hemodialysis patients, polytransfused patients) with chronic liver disease.Whereas the frequency of severe or fulminant hepatitis was similar in HBV infected patients (7.8%) and in HBV/HDV coinfected individuals (10%), the frequency of biphasic hepatitis was significantly (p < 0.005) higher in the latter patients (30%) than in those with classical hepatitis B (7.8%). Chronic evolution of the disease was observed in 3.9% of the patients with classical hepatitis B and in 5% of those who had evidence of simultaneous HBV/HDV infection. The 10 carriers of HBsAg who survived the acute HDV superinfection developed chronic delta hepatitis.These findings indicate that HDV is endemic in Turkey and that its prevalence is highest among chronic HBsAg-positive hepatitis patients, implicating HDV as a major cause of liver disease among urban Turkis.Corresponding author.     

Hepatitis B and delta virus infection among "at risk" populations in south east London.

STUDY OBJECTIVE--The hepatitis delta virus (HDV) contributes significantly to the morbidity and mortality of hepatitis B virus (HBV) infection, which is particularly prevalent among intravenous drug users and male homosexuals. A recent report has indicated that HDV first appeared in the South East London intravenous drug using population in 1982. The aim of the present study was to assess the prevalence of HDV in these two groups at risk of HBV infection in South East London. DESIGN--The study was a cohort analysis of HBV and delta virus serum markers, stratified temporally and with respect to intravenous drug use and sexual practice. SETTING--This was a population study of 372 consecutive intravenous drug users attending a local drug rehabilitation centre and 1481 subjects seen at a sexually transmitted disease clinic in the same area, during the years 1979 to 1988. MEASUREMENTS AND MAIN RESULTS--Of 372 intravenous drug users, 195 (52.4%) had evidence of current or past infection with HBV, of whom 17 had chronic HBV infection--a carriage rate of 8.7%. Twelve (70.6%) of these 17 also had chronic HDV infection--the first cases being identified in 1984. By comparison, 406 (27.4%) of the sexually transmitted disease clinic patients had been been exposed to HBV, 32 having chronic HBV--a carriage rate of 7.9% (7.5% v 9.4% among male homosexuals v male heterosexuals). Ten had been exposed to HDV (the first case in 1980) but only two (who did not admit to intravenous drug use) had chronic HDV infections (p less than 0.0005 v the rehabilitation centre patients). CONCLUSIONS--Although the HBV carriage rate is very similar in these two populations, chronic HDV infections were mainly confined to intravenous drug users. However, reports from the USA and France indicate spread of delta virus to the male homosexual community and, since there is clearly a pool of HDV in SE London, vaccination against HBV in these risk groups in likely to be cost-effective and should be actively encouraged.     

Epidemiology of viruses causing chronic hepatitis among populations from the Amazon Basin and related ecosystems

On the last twenty years, viral hepatitis has emerged as a serious problem in almost all the Amerindian communities studied in the Amazon Basin and in other Amazon-related ecological systems from the North and Center of South America. Studies performed on communities from Bolivia, Brazil, Colombia, Peru and Venezuela have shown a high endemicity of the hepatitis B virus (HBV) infection all over the region, which is frequently associated to a high prevalence of infection by hepatitis D virus among the chronic HBV carriers. Circulation of both agents responds mainly to horizontal virus transmission during childhood through mechanisms that are not fully understood. By contrast, infection by hepatitis C virus (HCV), which is present in all the urban areas of South America, is still very uncommon among them. At the moment, there is not data enough to evaluate properly the true incidence that such endemicity may have on the health of the populations affected. Since viral transmission might be operated by mechanisms that could not be acting in other areas of the World, it seems essential to investigate such mechanisms and to prevent the introduction of HCV into these populations, which consequences for health could be very serious.     

Unexpected low prevalence of delta antibodies in the east Amazon region and S?o Paulo: evidence for regional differences in the epidemiology of delta hepatitis virus within Brazil

Antibodies (anti-HD) to hepatitis delta virus (HDV) were tested by radioimmunoassay in 207 human serum samples from the eastern Amazon (states of Pará and Amapá) and S?o Paulo, Brazil. 42 Amazon HBsAg asymptomatic carriers were negative for anti-HD. 84 S?o Paulo HBsAg asymptomatic carriers were also negative. Among the 81 HBsAg patients from S?o Paulo with different liver diseases, only one had anti-HD. Liver biopsy of this chronic active hepatitis case was positive for HBsAg, HBcAg and HDAg in liver, by an immunoperoxidase technique. The low prevalence of HDV infections in S?o Paulo and eastern Amazon was unexpected and contrasts with the recent reports of high prevalence in the western Amazon region. Such regional differences emphasize the need for extensive and precise worldwide epidemiological studies of HDV.     

丁型肝炎病毒感染的血清流行病学观察

1987年4月至1988年10月间,本文应用酶联吸附法(EIA)对石家庄地区Ml例乙型肝炎病毒感染者进行了抗-HD的检测,共发现35例阳性,阳性率12.92%,其中男性阳性率14.06%(27/102),女性为10.13%(8/79),男女间差异无统计学意义(P>0.05),提示石家庄地区可能为丁型肝炎病毒感染的高发区.在这些人群中,慢性活动性肝炎、慢性迁延性肝炎和肝硬化的抗-HD阳性率明显高于HBsAg携带者,但三者相互间差异无统计学意义,表明合并或重香感染HDV对乙肝慢性化及肝硬化的形成具有重要的意义。本研究证明在乙型肝炎病毒感染人群中丁型肝炎病毐与年龄、性别、职业等因素关系不密切。     

Epidemiology of hepatitis delta virus (HDV) infection

Markers of hepatitis delta virus (HDV) infection have been detected all over the five continents. Geographical prevalence varied heavily: HDV infection is very rare in Far East Asia, but extremely frequent in Arabian countries, in Romania and in certain Indian populations of South America. In Europe and in the USA the infection is widely spread among high risk groups such as intravenous drug abusers and haemophiliacs,I Corresponding author.     

392例HBsAg阳性急慢性肝炎和携带者血清δ系统的研究

本文应用国产丁型肝炎病毒(HDV)酶联免疫试剂对392份HBsAg阳性肝炎和携带者血清进行了抗-HD、抗-HDIgM和HDAg测定,HDV总感染率为10.7％(42/392)。其中以重型肝炎组HDV标志检出率最高,达27.8％,然后依次为慢性肝病(15.5％)和急性乙肝(5.3％),HBsAg阳性携带者无1例阳性。本研究资料提示HDV感染对HBV感染在加重肝损害、促进肝脏炎症进展及慢性化方面均起十分重要作用。HDV标志与HDV RNA的测定亦有较高的符合率(96.9％)。     

High HBsAg and anti-delta carrier rate among asymptomatic Africans living on the campus of the University of Niamey, Niger

In 1984 and 1985, a non-random survey was conducted among healthy Africans living on the campus of the University of Niamey, Niger. Of 238 asymptomatic subjects, 17.6% carried hepatitis B surface antigen (HBsAg) in their serum, while 50.8% demonstrated protective anti-HBs antibodies. Antibodies to delta virus were detected in 29.3% of HBsAg-positive sera. This suggests that hepatitis B virus (HBV) and hepatitis delta virus (HDV) are common in Niger, and the factors that increase the likelihood of HBV transmission may also enhance the risk of HDV transmission.     

Evidence of a 1985-1987 outbreak of acute and chronic hepatitis in Egypt caused by a mutant hepatitis-B virus detected by spot-DNA hybridization test.

Sera from 65 acute and 113 chronic sporadic hepatitis were screened for serological markers of hepatitis-B virus (HBV) and hepatitis delta virus (HDV) and for HBV-DNA. The enzyme linked immune sorbent assay (ELISA) and dot-DNA hybridization tests were used. Two HBV-DNA probes and their labelling systems (biotin, radiolabelling with 32P and digoxigenin) were compared for sensitivity and specificity. The 65 acute sera had serological parameters of HBV infection in 38 (58%) when all these sera were HBsAg, IgM anti HBcAg positive plus HBeAg presence in 11/38 sera. Some of the acute sera had markers of acute HBV and HDV coinfection in 14 and superinfection in 13. Thus HBV with HDV represented 27 (41.5%) of the acute hepatitis in this study. Correlation of these serological markers with dot-DNA hybridization results showed that serum HBV-DNA was present in 36/38 (94.7%) of the acute HBV infection. In the case of acute HBV+HDV positive antigenemia 4/6 had serum HBV-DNA while 10/21 of acute HBV with anti-deltaV. IgM had serum HBV-DNA. There were four cases that gave HBV-DNA positivity in sera without combination of HBV markers suggesting infection with "mutant" HBV. In the chronic hepatitis sera there were markers of HBV past infection (IgG anti HBc in 63/113 and IgG anti HBs in 36/113). Yet, among these sera there was HBV-DNA positive signals (20/63 and 17/36) respectively. Analysis of some of these HBV markers also suggested infection with "mutant" HBV.     

Hepatitis delta virus and hepatocellular carcinoma: an update

Hepatitis delta virus (HDV) is a defective RNA virus that depends on the presence of hepatitis B virus (HBV) for the creation of new virions and propagation of the infection to hepatocytes. Chronic infection with HDV is usually associated with a worsening of HBV infection, leading more frequently to cirrhosis, increased risk of liver decompensation and hepatocellular carcinoma (HCC) occurrence. In spite of a progressive declining prevalence of both acute and chronic HDV infection observed over several years, mainly due to increased global health policies and mass vaccination against HBV, several European countries have more recently observed stable HDV prevalence mainly due to migrants from non-European countries. Persistent HDV replication has been widely demonstrated as associated with cirrhosis development and, as a consequence, development of liver decompensation and occurrence of HCC. Several treatment options have been attempted with poor results in terms of HDV eradication and improvement of long-term prognosis. A global effort is deemed urgent to enhance the models already existing as well as to learn more about HDV infection and correlated tumourigenesis mechanisms.Key words: Cirrhosis, epidemiology, hepatitis delta virus, hepatocellular carcinoma, natural history, treatment     

Prevalence of infections by hepatitis B, C, D and E viruses in Bolivia]

In Bolivia, no studies have been carried out specifically on hepatitis viruses. Thus, their prevalence and circulation patterns are virtually unknown. A seroepidemiologic study was performed from 1992 to 1996 to generate a preliminary idea of the overall prevalence of infection from hepatitis B, C, D, and E viruses (HBV, HCV, HDV, and HEV, respectively) in different Bolivian population groups. Prompted by the data obtained in other areas of Latin America, the study focused on indigenous communities in the Amazon region. In rural areas of the high Andean plateau, HBV infection showed an overall prevalence compatible with medium to low endemicity (11.2%), and no carriers of HCV or HDV antibodies were found. In two high-risk groups in the city of Cochabamba (homeless children and sexual workers), the prevalence of HBV infection was similar (11.6%) and could be considered low by comparison to that of similar population groups in Latin American urban centers. The prevalence of HCV (one positive case, or 0.5%) was similar to that found in similar population groups, although the small number of samples precludes drawing more definite conclusions. As has been noted previously with similar communities in tropical areas of South America, HBV infection is highly endemic in indigenous populations of the Bolivian Amazon (with an overall prevalence of 74.0%), but circulation of HCV has not been detected. It is a well-known fact that HBV is horizontally transmitted and that transmission can take place very early in life, but the mechanisms involved are unknown. By 10 years of age, more than half the population has already had the natural infection that, in approximately 10 more years will have affected virtually the entire population. The very low rate of positivity to HBsAg (1.6%), the absence of viral DNA in samples showing isolated positivity to anti-HBc, and the high prevalence of anti-HBs among individuals who show markers for natural infection (92.4%) suggest vertical transmission plays no role in persistent endemicity. So far, no outbreak of HDV infection has been documented in these communities, but the high endemicity shown by HBV points to the possibility of future outbreaks. Results obtained with tests for the detection of antibodies against HEV suggest that this virus is circulating widely in Bolivia and that it could have caused recent outbreaks in Cochabamba state. Vaccination against HBV in endemic populations is recommended as a short-term measure. Also recommended are actively searching for outbreaks and sporadic cases of hepatitis E in the entire country and performing additional research that will help in assessing the public health consequences of the situation described in this article.     

Epidemiological and molecular features of hepatitis B and hepatitis delta virus transmission in a remote rural community in central Africa

Hepatitis B virus (HBV) and hepatitis delta virus (HDV) occur worldwide and are prevalent in both urban and remote rural communities. In a remote village in Gabon, central Africa, we observed a high prevalence of HBsAg carriage and HDV infection, particularly in children and adolescents. The prevalence of HBsAg differed significantly by gender and age, females being more likely than males to carry the HBsAg during the first 10 years of life, while the prevalence was higher among males than females aged 11–20 years. We also characterised HBV and HDV strains circulating in the village. The principal HBV strains belonged to genotype HBV-E and subgenotype QS-A3. Complete genome analysis revealed for the first time the presence of the HBV-D genotype in Gabon, in the form of an HBV-D/E recombinant. Molecular analysis of HDV strains and their complete genomic characterisation revealed two distinct groups within the dominant HDV clade 8. Molecular analysis of HBV and HDV strains did not reveal vertical transmission within the families studied but rather horizontal, intrafamilial transmission among children aged 0–10 years. Our findings indicate that HBV is transmitted in early childhood by body fluids rather than by sexual contact. Health education adapted to the different age groups might therefore help to reduce HBV transmission. Young children should be vaccinated to control HBV infection in areas of extremely high prevalence.     

Low prevalence of hepatitis D (delta) virus infection in a nephrology unit in south India.

Fifty-five consecutive patients with end-stage renal disease entering haemodialysis programmes over a two-month period and 48 consecutive recipients of renal allografts during a period of 6 months were investigated for hepatitis B virus (HBV) and hepatitis D virus (delta) infection. HBV markers were present in 25 of the former and 40 of the latter. Of the 65 patients with HBV infection, 12 were not available for delta antibody screening. HBV infection was present for a mean of 2.5 months and 45.3% of those infected had clinical hepatitis; none had fulminant hepatitis. All the patients tested were negative for antidelta antibody. An additional patient on dialysis with delta superinfection and hepatic encephalopathy is also reported.     

Hepatitis B virus genotypes: a South Pacific perspective

87-91% but still, 0.6% of those that did respond to vaccination became infected. The infection rate of the vaccinated populations in the Pacific Islands ranged between 0.7 and 3.8%, which is comparable to Taiwan. A vigorous polyclonal response This communication discusses the current status of research in the hepatitis B virus in relation to the South Pacific. The hepatitis B virus (HBV) is a small DNA virus--3200 nucleotides. It has a circular genome and replicates through an RNA intermediate giving this DNA virus many characteristics similar to RNA viruses. Viral genomes can be single-stranded (+ or - sense) or double-stranded. If not vaccinated, infants born to HBeAg positive mothers (i.e. with high viral titer) have a 90% chance of being infected and becoming HBV carriers themselves. Mutants that affect the major antigenic determinant in HBV surface antigens are probably responsible for HBV infection despite immunization and mutants in the polymerase protein may render HBV resistant to therapy with nucleoside analogs. Within HBV seven genotypes A-G have been reported that is, HBV genotype A (HBVA), HBV genotype B (HBVB) etc. HBV is endemic worldwide with an estimated that 5% of the worlds population being carriers. Before the introduction of vaccination programs carrier rates varied between 5-30% in communities of these ethnic groups, and in some cases 80-90% of a community tested positive for HBV markers (i.e. were infected or had been infected). In Taiwan, of vaccinated babies born to HBV positive mothers, the proportion of those that responded to vaccination varied between will usually result in an acute infection and viral clearance. An associated problem with HBV, in the South Pacific, is the hepatitis delta virus (HDV). HDV is a satellite viroid-like RNA virus that requires HBV for replication. It can either co-infect with, or super-infect upon HBV infection resulting in acute infection and/or chronic infection respectively.     

Hepatitis B epidemiology and cultural practices in Amerindian populations of Amazonia: The Tupí-Mondé and the Xavánte from Brazil

Hepatitis B infection and disease are highly endemic in South America. Prevalences of positivity are particularly high in Amazonia, and among Amerindian peoples in particular. This paper reports the results of a seroepidemiological survey for hepatitis B virus (HBV) carried out among four Amerindian populations from the Brazilian Amazon region: Gavião, Suruí, Zoró and Xavánte. Rates of positivity to HBV serological markers (HBsAg, anti-HBs and/or anti-HBc) are very high for the four groups, ranging from 62.8 to 95.7%. It is argued that the high rates of positivity in the Amerindian groups dealt with in this study, as well as for other Amazonian populations, are related to a complex of cultural practices which enhance the likelihood of HBV transmission (bloodletting, scarification, tattooing and orally processed food, among others). The authors suggest that, due to unique patterns of interaction between sociocultural and environmental factors, HBV infection assumes a specific profile in native Amazonian societies.     

Prevalence of infection with hepatitis delta virus (HDV) among carriers of hepatitis B surface antigen in Amazonas State, Brazil

Serum samples were non-randomly obtained from apparently healthy inhabitants of 5 villages in the Amazonas State, Brazil. Sera were tested by enzyme immunoassay for the presence of hepatitis B surface antigen (HBsAg) and, if this was found, for antibody to hepatitis delta virus (HDV). Of 574 people tested, 96 (16.7%) were reactive for HBsAg and 33 of these (34.4%) for anti-HDV. The results were analysed according to sex, age and history of jaundice and showed a high prevalence of hepatitis B virus (HBV) and HDV infections in these asymptomatic persons, mainly in young people. The rates of prevalence observed in Amazonas for both HBV and HDV are perhaps among the highest in the world, demonstrating that these viruses are endemic in this region of Brazil.     

HTLV-1, HIV-1, hepatitis B and hepatitis delta in the Pacific and South-East Asia: a serological survey

Blood samples from 13 locations in the Pacific and South-East Asia were tested for evidence of infection with human T-cell lymphotropic virus type-1 (HTLV-1), human immunodeficiency virus (HIV-1), hepatitis B virus (HBV) and hepatitis delta virus (HDV). No samples were positive for antibody to HIV-1. Antibodies to HTLV-1 were found in samples from five locations, the maximum prevalence being 19%, in Vanuatu. Serological markers of HBV infection were found in all locations, the maximal prevalence being 88%, in Majuro, Micronesia. Antibodies to HDV in HBsAg positive sera were found in six locations with a maximum prevalence of 81% in Kiribati.     

Seroprevalence of hepatitis delta virus infection among subjects with underlying hepatic diseases in Chennai, southern India

Four hundred million people are carriers of hepatitis B virus (HBV) worldwide and approximately 5% of these are reportedly positive for hepatitis delta virus (HDV). Several reports indicate a declining trend in the occurrence of HDV infection in the north of tropical India. To our knowledge, no study has been conducted to evaluate whether a similar epidemiological change is occurring in southern India. Therefore we evaluated the seroprevalence of HDV among 153 individuals with HBV-related liver diseases in Chennai, and assessed any change in epidemiological pattern by comparing the results with seroprevalence figures reported previously. Of the 153 patients screened, nine (5.9%) were reactive to anti-delta antibodies, six (3.9%) presented an evidence of past infection (IgG anti-delta positive) and three (2.0%) showed anti-HDV IgM, suggestive of recent HDV infection. Alanine transaminase elevation was not significant in HDV-associated infection compared with HBV alone-infected acute viral hepatitis (AVH) (P=0.82) and chronic liver disease (P=0.77) patients. The anti-HDV positivity in AVH was considerably low (6.6%), compared with previous Indian reports varying from 10.7% to >30%. HDV infection was relatively low and seems to play a minor determining factor of liver diseases in the tropical south Indian population.