Hepatitis B virus (HBV) infection is a worldwide health problem. The aim of the present study was not only to determine the prevalence of HBsAg in children of HBV-infected parents but also to identify all HBSAg-positive family members to protect as many children, in the present and future, as possible. The study was carried out with the participation of 2113 family members (1205 children, 453 mothers, and 455 fathers) at Sivas SSK Hospital, Turkey. They were screened for HBV markers using standard enzyme immunoassay between September 2001 and March 2005. The prevalence of any HBV markers and HBsAg among family members of index cases was 50.5% and 30.5% respectively. HBsAg carrier rate was higher among fathers (61%) than mothers (47%), (P<0.05). The children of mother index cases had higher rates of HBsAg compared with the children of father index cases (P<0.01). Our results suggest that intra-familial childhood horizontal transmission (especially mother-to-child) is important for HBV transmission in the Turkish community, and highlights the need for screening of adult siblings and mothers of adult HBsAg carriers in addition to their spouses and children.

Hepatitis B is endemic in the Amazon region.

Serological markers for hepatitis B virus (HBV) were determined in 266 household members for hepatitis B surface antigen (HBsAg)-positive women (G1) and 395 household members for HBsAg-negative women (G2), randomly selected in Acre State Women's Medical Care Program, in order to evaluate the prevalence of HBV in this population. Before blood sample collection an epidemiological questionnaire was applied.

The overall prevalence of HBV carriers (HBsAg) and exposed individuals (anti-HBc, IgG) was, respectively, 21.1% and 60.5% in G1 and 2.8% and 27.4% in G2 (P < 0.0000001). The frequency of HBsAg was higher among siblings from group G1 (75%) compared to the absence of any HBsAg-positive sibling in G2 (P < 0.00006). The HBV markers in other family members was as follows: G1 parents, 27.3% vs 4.5% (P < 0.03), sexual partners, 21.1% vs 2.5% (P < 0.04), and offspring, 10.4% vs 1.5% (P < 0.04). A low prevalence of HBsAg and anti-HBc (IgG) was observed for the last offspring of G2 mothers compared to the high prevalence among children of G1 mothers (0% vs 18.2%, P < 0.01 and 2.3% vs 59.1%, P < 0.0000005, respectively), with children younger than 1 year being the most affected. The frequency of the habit of sharing toothbrushes and the presence of at least one HBsAg carrier were higher in G1 than in G2 (P < 0.0001 and P < 0.000002), respectively. Genotypes A, D and G were found to be predominant by Innolipa test. There were cases that reacted to more than one genotype.

Intrafamilial transmission of HBV is evident in the present study and is possibly associated with the presence of more than one HBV carrier in the family and the shared use of toothbrushes among household contacts. Genotype analysis confirms intrafamilial transmission.

India, with its 43 million hepatitis B virus (HBV) carriers and absence of any national immunization programme, adds a substantial number of HBV infections to the HBV carrier pool yearly. The aim of this study was to assess the spread of HBV infection in families with an infected member and to identify the family members with the highest risk of infection in our community.

A total of 937 serum samples from 215 HBV-infected cases and 722 members of their households were screened prospectively for markers of HBV by commercial enzyme-linked immunosorbent assay.

Among family members, 140 (19.4%) were HBsAg positive and 272 (37.6%) were negative for HBsAg but positive for either anti HBc or anti HBs. There were 145 HBsAg-positive adults among the index cases whose 133 adult siblings, 59 spouses and 59 mothers participated in the study. Interestingly, 28.81% mothers and 28.57% adult siblings of these adult index cases were positive for HBsAg compared with only 8.75% of their spouses (P < 0.001). Only 15.2% of the HBsAg-positive women in the childbearing age group were found to be HBeAg positive.

Our results suggest that intrafamilial childhood horizontal transmission is important for HBV transmission in our community, and highlight the need for screening of adult siblings and mothers of adult HBsAg carriers in addition to their spouses and children.

The aim of this study was to describe the distribution of hepatitis B virus markers among the autochthonous and immigrant multicultural populations of Riau province, Indonesia, in order to define the groups at risk and their infrastructure. This investigation was part of a large hepatitis B vaccination study. A total of 9701 healthy individuals, aged 5 years or older and living in the urbanised area of Batam, near Singapore, and on the surrounding islands were included. Socio-epidemiological data were collected, blood was drawn, and sera were tested for antibodies to hepatitis B core (anti-HBc) and surface antigen (anti-HBs). Anti-HBc-positive sera were tested against hepatitis B surface antigen (HBsAg). All tests comprised immunoassays from Roche (Germany) using Elecsys 2010. Complete data were available from 9314 subjects. The results showed relatively low prevalences of anti-HBc (a marker of a previous hepatitis B infection) and HBsAg in the 5-year-old chiLdren (5.8 and 1.9%, respectively) that increased continuously with increasing age. High anti-HBs levels (>1000 IU/L) were found in all age cohorts, indicating a lifelong threat of active hepatitis B infection. In conclusion, the transmission profile of hepatitis B appeared to be mainly horizontal (person-to-person) in the highly endemic region studied. Vertical transmission was less than 5%. The horizontal transmission routes included non-sexual activities of life since children <10 years of age also showed considerable infection rates. The results underline the need for catch-up hepatitis B vaccination programs for children and adults.

This paper reports the prevalence rate of hepatitis B antigen (HBsAg) amongst the Hong Kong Chinese adolescents (age 11 to 19), and the risk factors associated with HBsAg positive. The study is cross sectional and 1,580 students were randomly selected from 12 secondary schools in four regions of Hong Kong. For those subjects who agreed to participate and were randomly selected, their blood was tested for HBsAg and anti-HBs. The overall prevalence of HBsAg positive was reported to be 5.8% (7.9% in male and 4.1% in female), lower than 8.1% in 1978. Males, those born in Mainland China and family history of carriers had higher prevalence of HBsAg positive (7.9% vs 4.1%, 12.2% vs 4.7%, 52.9% vs 3.8% respectively) with statistical significance. Males and those born in mainland China were found to have significantly higher odds ratio 1.8 (95% CI. 0.98-3.52) and 4.4 (95% CI. 2.2-8.8) respectively of HBsAg positive by multivariate analysis. Findings suggest that family history of carriers and those born in endemic area are at a higher risk. Therefore it is worthwhile to consider vaccination programme for adolescents to reduce the carrier rate, and to also reduce the injection amongst the adults by horizontal transmission.

The costs and projected benefits of universal screening for hepatitis B virus (HBV) infection in pregnant women in East Anglia are calculated and compared with current practice. By adjusting data from West Midlands region for ethnicity, the prevalence of maternal hepatitis B surface-antigen (HBsAg) positivity in East Anglia is predicted to be 0.083% (1 in 1200). Published data on health risks of perinatal HBV infection and on immunisation efficacy are used to derive benefits of screening. The marginal direct cost of screening is identified from regional sources. Current clinical practice in East Anglia identifies 7 surface-antigen positive mothers per year, whereas 22 are expected. Routine antenatal screening in East Anglia would prevent 2.6 additional childhood carriers per year (compared with current practice), resulting in the prevention of 0.7 deaths per year occurring 40-50 years in the future. The direct cost per (undiscounted) life-year saved would be Pounds 2437, not including savings on treatment for chronic hepatitis B infection. Routine prenatal screening for maternal HBsAg should be introduced without delay and continue even if HBV vaccination is introduced into the UK childhood immunisation schedule.

Although Singapore is in an endemic region for hepatitis B infection, the hepatitis B carriage rate of 5-6% is relatively low. The highest positivity rates for hepatitis B surface antigen (HBsAg) are found in the paediatric age group, with another peak in 40-49 year olds. Studies suggest that, although perinatal transmission is an important route of infection, most children acquire the virus through horizontal transmission between family members. Viral replication continues at a high rate in young carriers and tends to slow down with increasing age. Up to 50% of hepatitis B carriers in Singapore have chronic hepatitis, shown by raised serum ALT values and liver histology, and about 10% are infected with the precore mutant virus. About 20% of carriers have cirrhosis. Among patients with HCC, up to 75% are HBsAg positive, of whom 45% are still viraemic. Mass vaccination against hepatitis B was introduced into Singapore on a voluntary basis in 1983, with compulsory vaccination of babies born to HBeAg positive mothers since 1985. The number of cases of acute hepatitis B has fallen by 60% between 1989 and 1995 although the problems of the longterm complications of chronic hepatitis B still need to be tackled.