Hepatitis B infection among patients attending a sexually transmitted diseases clinic in Rio de Janeiro, Brazil

Hepatitis B virus (HBV) has a low endemicity in Rio de Janeiro, Brazil. Sexual transmission must play an important role in this virus, but the prevalence and risk factors have never been properly investigated. The aim of this paper is to determine the prevalence and risk factors for HBV infection in patients attending a Sexually Transmitted Diseases Clinic of the Universidade Federal Fluminense, from the State of Rio de Janeiro, Brazil. In a retrospective study, HBV seroprevalence was investigated in 440 patients. Serum of each patient was assayed for antibodies against hepatitis B core antigen (anti-HBc), hepatitis B surface antigen (HBsAg) and antibodies against hepatitis B surface antigen (anti-HBs). Demographic and risk factor data were extracted from clinic notes. The overall seroprevalence of exposure markers for HBV (anti-HBc, HBsAg and anti-HBs) were 13%, 3.4% and 8.5% respectively. Homo/bisexual behaviour, anal intercourse, HIV infection, positive serology for syphilis and blood transfusion were predictors of the HBV exposure. Among demographic data, age and place of birth were associated with the anti-HBc seropositivity.     

Retrospective review of the prevalence of hepatitis B virus in several population groups

Nine different groups of individuals studied from 1969 to 1985 were tested for Hepatitis B Virus (HBV) markers. In 8 groups only HBsAg in serum was tested, in another group: tissular HBsAg, and in two of those groups: serum HBsAg, anti-HBs and anti-HBc. Mean HBsAg prevalence in groups similar to general population was 0.64%; 5% in cirrhotics; HBV prevalence in haemophiliacs was 18.87% by testing serum for HBsAg and anti-HBs; serum HBsAg prevalence in Viral Chronic Active Hepatitis was 43.24%; and Hepatocellular Cancer (HCC) group had a prevalence for HBV of 13.04% when only tissular HBsAg was tested, and 54.29% when serum HBsAg, anti-HBs and anti-HBc were tested in all patients. Costa Rica has a low HBV markers prevalence only similar to what is found in industrial developed countries.     

Hepatitis B and C in the hemodialysis unit of Tocantins,Brazil: serological and molecular profiles

A survey was conducted in the hemodialysis population of the state of Tocantins, Brazil, aiming to assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, to analyze associated risk factors, and also to investigate these viruses genotypes distribution. During January and March 2001, all patients (n = 100) were interviewed at the unique dialysis unit in Tocantins. Blood samples were collected and serum samples were screened for HBV serological markers. Hepatitis B surface antigen positive samples were tested for HBV DNA. All samples were also tested for anti-HCV antibodies and HCV RNA. An overall prevalence of 45% was found for HBV infection (4% were HBsAg/anti-HBc positive, 2% were anti-HBc only and 39% had anti-HBc/anti-HBs markers). Concerning HCV infection, anti-HCV and HCV RNA were detected in 13% and 14% of the subjects, respectively. Three patients were HCV RNA positive and anti-HCV negative, resulting in an overall HCV prevalence of 16%. Univariate analysis of risk factors showed that only shift and length of tile on hemodialysis were associated with HBV and HCV positivity respectively. Among the four HBsAg-positive samples, HBV DNA was detected in three of them, which were identified as genotype A by restriction fragment length polymorphism (RFLP) analysis. All 14HCV RNA-positive samples were genotyped by INNO-LiPA. Genotypes la and 3a were found in 85% and 15%, respectively. The present data show low HBsAg and HCV prevalence rates. The risk factors associated with HBV and HCV positivity suggest that nosocomial transmission may influence in spreading these viruses in the dialysis unit studied.     

Patterns of hepatitis B virus infection in Brazilian human immunodeficiency virus infected patients: high prevalence of occult infection and low frequency of lamivudine resistant mutations

Hepatitis B virus (HBV) molecular profiles were determined for 44 patients who were infected with human immunodeficiency virus (HIV) type 1 and had antibodies to the hepatitis B core antigen (anti-HBc), with and without other HBV serological markers. In this population, 70% of the patients were under lamivudine treatment as a component of antiretroviral therapy. HBV DNA was detected in 14 (32%) patients. Eight out of 12 (67%) HBsAg positive samples, 3/10 (30%) anti-HBc only samples, and 3/22 (14%) anti-HBs positive samples were HBV DNA positive. HBV DNA loads, measured by real time polymerase chain reaction, were much higher in the HBsAg positive patients (mean, 2.5 x 10(9) copies/ml) than in the negative ones (HBV occult infection; mean, 2.7 x 10(5) copies/ml). Nine out of the 14 HBV DNA positive patients were under lamivudine treatment. Lamivudine resistant mutations in the polymerase gene were detected in only three patients, all of them belonging to the subgroup of five HBsAg positive, HBV DNA positive patients. A low mean HBV load (2.7 x 10(5) copies/ml) and an absence of lamivudine resistant mutations were observed among the cases of HBV occult infection.     

Prevalence of hepatitis B viral markers in Vietnamese blood donors

Serum samples were assayed using radioimmunoassay in 573 Vietnamese blood donors living in Hano? (North Viet Nam). 66 (11.5%) subjects were HBsAg-positive. Of these 66 HBsAg carriers, 17 (25,8%) were positive for hepatitis B e antigen (HBeAg) and 43 (65.1%) for antibody to HBeAg (anti-HBe). 22 (3.8%) subjects were positive for antibody to hepatitis B core antigen (anti-HBc) alone. 402 (70.2%) subjects were positive for antibody to HBsAg (anti-HBs). This anti-HBs percentage increased with age. Only 83 (14.5%) subjects were negative for all hepatitis B viral (HBV) markers. This no HBV markers percentage decreased with age. The chi 2 test showed a non significant difference for frequencies of HBsAg, anti-HBc alone, anti-HBs but a significant one for frequencies of no HBV markers in men and women.     

Epidemiologic features of hepatitis B virus infection in northern Labrador.

We studied the epidemiologic features of hepatitis B virus (HBV) infection in northern Labrador to determine the prevalence of the infection and to obtain a database to develop a vaccination strategy. The study population included seven communities in which five ethnic groups were represented: Inuit, Innu, mixed Inuit and European ancestry ("settler"), nonnative/nonsettler transient population ("white") and people of Innu-white or Innu-Inuit origin ("mixed"). Blood samples from 2156 people (62% of the area residents) were tested for antibody to HBV core antigen (anti-HBc), HBV surface antigen (HBsAg), HBV e antigen (HBeAg), anti-HBc IgM and antibody to the surface antigen (anti-HBs). The overall crude prevalence rate of HBV seromarkers was 14.7% and the HBsAg carrier rate at least 3.2%; the rates were highest for Inuit (26.4% and 6.9% respectively), followed by settler (10.0% and 1.9% respectively) and Innu (7.6% and 0.4% respectively); the white and mixed groups had the lowest overall rates (2.5% and 3.3% respectively). Although the overall prevalence rates were about the same for the two sexes, the HBsAg carrier rate was higher in males (male:female ratio 1.6:1.0). No HBV carriers were positive for HBeAg or anti-HBc IgM antibody. The rate of exposure to HBV was 4% for those below the age of 20 years and reached a peak for those aged 45 to 54 years (85% for Inuit, 40% for settlers and 37% for Innu). There was also a wide variation in the age-standardized prevalence rates (0% to 27.9%) among the ethnic groups in the seven communities surveyed.     

Increased severity and morbidity of acute hepatitis in drug abusers with simultaneously acquired hepatitis B and hepatitis D virus infections.

Hepatitis D virus (delta agent) markers were present in 111 (36%) of 308 intravenous drug abusers who were positive for hepatitis B surface antigen (HBsAg), 52 of these having hepatitis D virus antigenaemia. IgM antibody to hepatitis B core antigen (anti-HBc IgM) was present in 92 out of 95 subjects tested, indicating that hepatitis D virus and hepatitis B virus infections had been acquired simultaneously. Hepatitis D virus markers were present in three out of four patients with fulminant hepatitis, and in 80 of 223 (36%) with mild or moderate hepatitis compared with four of 29 (14%) of those who were asymptomatic. These proportional differences were significant (p less than 0.001). Hepatitis D virus markers were present in twice as many patients positive for anti-HBc IgM requiring admission to hospital with acute hepatitis compared with outpatients attending a drug treatment centre. Tests on one patient showed complete disappearance of HBsAg, but hepatitis D antigen (HDAg or delta antigen) and hepatitis B e antigen (HBeAg) were still present in serum samples. All five patients with chronic active hepatitis had hepatitis D antibody (anti-HD) compared with seven of 24 (29%) with chronic persistent hepatitis (p = 0.008). Blocking anti-HD persisted for long periods after simultaneous infections with hepatitis B virus and hepatitis D virus but at lower titres than in patients with chronic liver disease.     

Seroprevalence of Hepatitis B virus infection among an Afro-descendant community in Brazil

Furnas dos Dionísios is an Afro-Brazilian black community whose descendants were mainly fugitive slaves that established themselves in the State of Mato Grosso do Sul (MS), Brazil. The population is comprised mainly of low socioeconomic individuals who are engaged in agricultural activities. The objective of this study was to investigate the prevalence of hepatitis B (HB) and its correlation with epidemiological data obtained from the community. The studied population totaled 260 individuals with ages varying from 1 to 79 years (median 20). One hundred thirty-three (51.2%) were females and 127 (48.8%) were males. A high prevalence for anti-HBc was observed (42.7%), with present infection detected in 9.2% of the subjects who were also HB surface antigens (HBs Ag) positive; 27.3% were anti-HBc and anti-HBs reactive, and 6.2% had anti-HBc as only marker. The prevalence for anti-HBc was proportional to age, reaching its highest peak in age categories greater than 50. No serological marker was detected in children under the age of 2 years, however anti-HBc was present in 12 subjects with ages between 2 and 14 years, of these 8 (7.4%) were HBsAg positive. Among individuals over the age of 15 years, 99 were anti-HBc reactive, of these 16 (10.5%) were also HBsAg positive, thus suggesting an increased prevalence of HBV carriers among children and adolescents. The risk factors observed in this community that were significantly associated with anti-HBc positivity were age (over 20 years) and having an anti-HBc positive mother. Both HBeAg and anti-HBe were detected in 44.4% of the samples tested. HBsAg subtypes found in the studied population were adw2 (77.7%) and ayw2 (23.3%). While intrafamilial transmission was most likely responsible for HBV infection among children, other routes such as sexual contact might be considered for individuals with ages over 15 years.     

Rare Detection of Occult Hepatitis B Virus Infection in Children of Mothers with Positive Hepatitis B Surface Antigen

The prevalence of occult Hepatitis B virus (HBV) infection in children was considerably varied from 0.1–64% in different reports. In this study we aimed to investigate the prevalence of occult HBV infection among the children born to mothers with positive hepatitis B surface antigen (HBsAg) in Jiangsu, China. Serum samples were collected from 210 children of 207 mothers with positive HBsAg. HBV serological markers were detected by ELISA and HBV DNA was detected by nested PCR. Homology comparison of HBV sequences recovered from the child and mother was used to define the infection. Three children (1.43%) were positive for HBsAg, in whom the HBV pre S and S gene sequence in each child was identical to that in her mother. Of the 207 HBsAg-negative children, nine displayed HBV DNA positive by two nested PCR assays using primers derived from S and C genes. However, the sequence alignment showed that the sequences in each child were considerably different from those in his/her mother. Therefore, the sequences amplified from the children were very likely resultant from the cross-contaminations. Furthermore, the nine children with ‘positive HBV DNA’ were all negative for anti-HBc, and one had anti-HBs 3.42 mIU/ml and eight others had anti-HBs from 72 to >1000 mIU/ml, indicating that the nine children were less likely infected with HBV. Therefore, none of the 207 HBsAg-negative children of HBV-infected mothers was found to have occult HBV infection. We conclude that the prevalence of occult HBV infection in vaccinated children born to HBsAg positive mothers should be extremely low. We recommend that homology comparison of sequences recovered from the child and mother be used to define the occult HBV infection in children born to HBV infected mothers.     

Large-scale survey of hepatitis B virus infection in families

To investigate HBV transmission in families on three islands in Okinawa, Japan, prevalence of HBV markers in two groups of inhabitants was determined. One group consisted of members of families in which there was at least one HBsAg carrier (carrier families); the other group consisted of members of families in which there were no HBsAg carriers (non-carrier families). A total of 3,261 serum samples were collected from subjects on Iriomote Island, Hateruma Island, and Yonaguni Island. These samples were tested for HBsAg by reversed passive hemagglutination (RPHA) and for antibody to hepatitis B core antigen (anti-HBc) by radioimmunoassay. Overall prevalences of HBsAg and anti-HBc were 8.2 and 65.8 per cent respectively. The prevalence of anti-HBC among members of carrier families (80.8%) was significantly higher than that among members of non-carrier families (61.6%) (P less than 0.001). The prevalence of anti-HBc among members of carrier families was higher in all age groups, and was particularly so in children. Within carrier families, the prevalence of anti-HBc was significantly higher in families in which there was at least one HBsAg carrier with HBeAg (94.5%) than in families with no HBeAg-positive carriers (76.1%). This difference was especially marked in young children. These data suggest that in families with HBsAg carrier(s), the risk of transmitting HBV to members, particularly to young children, is higher than in families without carriers, and that the risk is further increased in families with HBeAg-positive carrier(s).     

Genetic variability of hepatitis B virus isolates among population of Shuryskarsky area of Yamal-Nenets autonomous region

The purpose of this work was to determine occurrence of serological markers of hepatites B and to describe subtypes of a superficial antigen and genotypes of hepatitis B virus (HBV) isolates among indigenous population of Yamal-Nenets Autonomous Region (YNAR), Russia. METHODS: We investigated 657 serum samples from inhabitants of Shuryskarsky area of YNAR. ELISA method was used to define the hepatitis B markers: HBsAg, anti-HBs (total) and anti-HBc (IgG and IgM). The HBsAg-positive samples were PCR-tested for the presence of HBV DNA. Genotyping of isolates was by sequencing of the Pre-Sl/Pre-82/S region of HBV genome and phylogenetic analysis. Definition of HBsAg subtypes was executed by two methods: ELISA with subtype-specific monoclonal antibodies and S-gene nucleotide sequence analysis. RESULTS: The following occurrence of hepatitis B markers was observed: HBsAg - 3.2%, anti-HBs (total) - 36.2%, anti-HBc IgG - 30.3%, anti-HBc IgM - 1.6%. Frequency of carrying even one of the markers in the observed population was 47.5%. HBV DNA was found in 17 HBsAg-positive samples. Pre-SI, Pre-S2 and S regions sequences were determined for all HBV DNA-positive samples. The phylogenetic analysis showed an accessory of all investigated HBV isolates to genotype D. HBsAg subtypes distribution appeared the following: ayw2 - 23.5%, ayw3 - 70.6%, adw2 - 5.9%. Results of definition of the subtype ELISA method and by the analysis of S gene nucleotide sequences have coincided in 10/11 (90.1%) cases. CONCLUSIONS: The indigenous population of Shuryskarsky area of YNAR belongs to groups with average HBV carrying. Absolute domination of genotype D (subtypes ayw2, ayw3 and adw2) was revealed. High percentage of concurrence of HBsAg subtypes detected by the ELISA method and method of the analysis of S gene primary structure (90%) was observed. Sequencing of HBV S-gene is preferable to define HBsAg subtypes.     

A seroepidemiologic study of hepatitis B virus infection among barbers in Huangshi City, Hubei, China

Between March and August 1986 in Huangshi City, serum samples were collected from 316 apparently healthy barbers as a study group, as well as from 361 healthy employees of department stores as a control group. They were tested for hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs) and antibody to hepatitis B core antigen (anti-HBc) by enzyme-linked immunoadsorbent assays. Barbers showed a prevalence higher than that in controls for HBsAg (16.8 vs. 9.2%, P less than 0.01), anti-HBs (67.1 vs. 45.9%, P less than 0.001), and anti-HBc (39.2 vs. 21.2%, P less than 0.001). The prevalence of at least one marker of hepatitis B virus (HBV) infection was significantly higher in barbers than in controls (86.1 vs. 61.7%, P less than 0.001). Although the socioeconomic status and education level did not correlate with the frequency of HBV markers, the prevalence of HBsAg increased in parallel with the duration of practice. Because of their high risk for HBV infection, barbers need to be screened for markers of HBV infection on a routine basis, and are prime candidates for immunoprophylaxis with hepatitis B vaccine.     

Seroepidemiologic study of adult T-cell leukemia virus (ATLV) and hepatitis B virus infection in Okinawa, Japan

A total of 2,283 serum samples were collected from healthy subjects in three islands of the Yaeyama district of Okinawa, Japan. These sera were tested for the presence of hepatitis B surface antigen (HBsAg), for antibody to hepatitis B core antigen (anti-HBc), and for antibody to adult T-cell leukemia-associated antigen (anti-ATLA). Correlation between hepatitis B virus infection and adult T-cell leukemia virus (ATLV) infection was determined by using the prevalence rates for three virus markers. Overall prevalence of HBsAg, anti-HBc and anti-ATLA was 6.5%, 57.4%, and 17.9%, respectively. Age-specific prevalence of anti-HBc and anti-ATLA increased with age, but that of HBsAg did not. Sex-specific prevalence of HBsAg was significantly higher in males than in females, but that of anti-ATLA was significantly higher in females than in males. Statistical analysis revealed that prevalence of anti-ATLA was significantly higher in HBsAg-positive persons and HBsAg-negative/anti-HBc-positive persons than in those negative for HBsAg and anti-HBc. These data suggest that hepatitis B virus-infected persons have a significantly higher chance of adult T-cell leukemia virus infection than those without hepatitis B virus infection in the area studied.     

Hepatitis B virus infection profile in hemodialysis patients in Central Brazil: prevalence, risk factors, and genotypes

Hemodialysis patients are at high risk for hepatitis B virus (HBV) infection. A survey was conducted in the hemodialysis population of the state of Goiás, Central Brazil, aiming to assess the prevalence of HBV infection, to analyse associated risk factors, and also to investigate HBV genotypes distribution. A total of 1095 patients were interviewed in 15 dialysis units. Serum samples were screened for HBV serological markers by enzyme-linked immunosorbent assay. Hepatitis B surface antigen (HBsAg) positive samples were tested for HBV DNA by polymerase chain reaction and genotyped by restriction fragment length polymorphism. Global HBV infection prevalence was 29.8% (95% CI: 27.1-32.5). Multivariate analysis of risk factors showed that male gender, length of time on hemodialysis, and blood transfusion before 1993 were associated with HBV positivity. HBV DNA was detected in 65.4% (17/26) of the HBsAg-positive samples. Thirteen of 17 HBV DNA positive samples were genotyped. Genotype D (61.5%) was predominant, followed by A (30.8%), while genotype F was detected in only one (7.7%) sample.     

A case of hepatitis B reactivation in an anti-HBs positive, anti-HBc positive non-Hodgkin’s lymphoma patient

Dear Editor, We report a case of HBV reactivation in an anti-HBs positive,anti-HBc positive non-Hodgkin's lymphoma patient.Hepatitis B virus (HBV) reactivation is a well-recognized complication of patients undergoing chemotherapy or immunosuppressive therapy for lymphomas.The presence of antibodies to the hepatitis B surface antigen (anti-HBs) has been identified to be a factor preventing HBV reactivation in patients with occult HBV infection receiving chemotherapy.In this paper,we present a non-Hodgkin Lymphoma patient who,before immunosuppressive therapy,displayed positive anti-HBs and positive antibodies to hepatitis B core antigens (anti-HBc),as markers of resolved HBV infection,and developed hepatitis B surface antigen (HBsAg) and high viraemia with an HBV escape mutant after rituximabbased administration.The sequencing data revealed HBV genotype D with two known escape mutations,P120S.     

Seroepidemiology of hepatitis B virus infection and high rate of response to hepatitis B virus Butang vaccine in adolescents from low income families in Central Brazil

In order to evaluate the seroepidemiology and response to Butang vaccine in adolescents from low income families in Central Brazil, blood samples of 664 adolescents were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) markers, and multiple logistical regression analysis was carried out to determine variables associated with hepatitis B virus (HBV) infection markers. further, three 20 microg Butang vaccine doses were offered to all susceptible individuals (n = 304). Among those who accepted them (n = 182), the seroresponse was evaluated in 170 individuals by quantitative anti-HBs. an overall hbv prevalence of 5.9% was found: four adolescents were HBsAg positive, 24 were anti-HBc, anti-HBs-reactive, and 11 were anti-HBc only. The analyse of risk factors showed that age 16-19 years, place of birth outside Goiás, school B and body piercing were statistically associated with HBV infection markers (p < 0.05). All 170 adolescents responded to Butang, and a geometric mean titer (gmt) of 4344 mUI/ml was obtained. these results reinforce the importance of hepatitis b vaccine in adolescents despite of the hbv regional endemicity, and suggest that three doses of 20 microg of the Butang should guarantee protective anti-hbs levels to individuals at a critical time for hepatitis b acquiring such as latter adolescence and adulthood.     

Importance of markers of hepatitis B virus in alcoholic liver disease.

To determine the importance of the presence of serological markers of hepatitis B virus infection in patients with alcohol related liver disease we compared cumulative alcohol intake and clinical and histological features in patients with markers of hepatitis B virus infection and in those without. Hepatitis B surface antigen (HBsAg) was detected in five (2%) out of 285 patients studied and antibody to HBsAg (anti-HBs) in 41 (14%); one patient had antibody to hepatitis B core antigen alone. The combined prevalence of markers of hepatitis B virus infection was similar in patients with alcoholic cirrhosis (18%) and precirrhotic liver disease (13%). Two patients positive for HBsAg had histological features of both alcoholic liver disease and chronic active hepatitis, with stainable HBsAg. Patients with anti-HBs were, however, histologically indistinguishable from patients without markers, and the mean cumulative alcohol intake of patients with anti-HBs was similar to or even higher than that of patients with liver disease of comparable severity who had no evidence of previous infection. The presence of markers of hepatitis B virus infection was related to former residence in countries with a high prevalence of the infection and to previous parenteral treatment and blood transfusions. Infection with hepatitis B virus does not enhance the development of chronic liver disease in heavy drinkers, except in the small number who remain positive for HBsAg.     

Investigation of Occult Hepatitis B Virus Infection in Anti-HBc Positive Patients from a Liver Clinic

Occult hepatitis B infection (OBI) is manifested by presence of very low levels (<200IU/mL) of Hepatitis B viral DNA (HBV DNA) in the blood and the liver while exhibiting undetectable HBV surface antigen (HBsAg). The molecular mechanisms underlying this occurrence are still not completely understood. This study investigated the prevalence of OBI in a high-risk Australian population and compared the HBV S gene sequences of our cohort with reference sequences. Serum from HBV DNA positive, HBsAg negative, and hepatitis B core antibody (anti-HBc) positive patients (study cohort) were obtained from samples tested at SEALS Serology Laboratory using the Abbott Architect, as part of screening and diagnostic testing. From a total of 228,108 samples reviewed, 1,451 patients were tested for all three OBI markers. Only 10 patients (0.69%) out of the 1,451 patients were found to fit the selection criteria for OBI. Sequence analysis of the HBV S gene from 5 suspected OBI infected patients showed increased sequence variability in the ‘a’ epitope of the major hydrophilic region compared to reference sequences. In addition, a total of eight consistent nucleotide substitutions resulting in seven amino acid changes were observed, and three patients had truncated S gene sequence. These mutations appeared to be stable and may result in alterations in HBsAg conformation. These may negatively impact the affinity of hepatitis B surface antibody (anti-HBs) and may explain the false negative results in serological HBV diagnosis. These changes may also enable the virus to persist in the liver by evading immune surveillance. Further studies on a bigger cohort are required to determine whether these amino acid variations have been acquired in the process of immune escape and serve as markers of OBI.     

Hepatitis B in a hospital for the mentally subnormal in southern England.

The prevalence of hepatitis B viral (HBV) infection was assessed in 340 patients and 268 staff in a hospital for the mentally subnormal in Wessex. Hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen, antibody to HBsAg, e antigen (eAg), and antibody to eAg were used as markers of such infection. Forty patients and 10 staff had evidence of recent or current infection, while 149 patients and 50 staff had evidence of past infection. HBV markers were more common in mongols, epileptics, patients with cerebral palsy, and those of lower mental grades and reached a peak after 5-15 years of hospitalisation. eAg was detected in 12 out of 26 patients with HBsAg but in none of the four staff with HBsAg. Abnormal liver function values were found in 24 (60%) of the patients with recent or current HBV infection but in only 30 (19%) of those without HBV markers. Among the staff the prevalence of HBV markers correlated with the duration of employment and degree of contact with patients. Of those with recent or current infection, 4 (40%) had abnormal liver function values compared with 25 (12%) of those without HBV markers. Despite the high prevalence of markers clinically overt hepatitis B was rare.