Hepatitis B virus infection in children of HBV-related chronic liver disease patients: a study of intra-familial HBV transmission

Seroconversion among children with HBsAg-positive mothers in Indonesia and factors affecting the anti-HBs titers

Background and aim

Around 2% of newborns are at risk of hepatitis B virus (HBV) infection from their mothers. To prevent this, infants born to HBsAg-positive mothers are given hepatitis B immune globulin (HBIG) and hepatitis B (HB) vaccine as immunoprophylaxis. This study aims to investigate the efficacy of immunoprophylaxis in infants born to HBsAg-positive mothers and the contributing factors.

Methods

The study was conducted on a group of 87 children, ranging from nine months to under 36 months, born to HBsAg-positive mothers and received immunoprophylaxis within 24 h after birth followed by a national immunization schedule at the Community Health Center (CHC) in three administrative cities of DKI Jakarta. We measured the levels of HBsAg and anti-HBs, and utilized ordinal logistic regression models to identify factors that influence the anti-HBs titers after vaccination.

Results

Out of 87 children, only one child had positive HBsAg results. The data showed that 88.5% of the children had seroprotection with anti-HBs levels ≥10 mIU/mL. Additionally, 48.3% of the children had a high protective response with anti-HBs levels ≥100 mIU/mL, while 11.5% had a non-protective response. Children under one year of age, with a family history of HBV carriers, and who received five doses of the HB vaccine exhibited higher levels of anti-HBs titer category with adjusted OR 3.9 (95%CI: 1.3-11.6), 5.3 (95%CI: 1.1-27.4), and 8.3 (95%CI: 2-34.8), respectively.

Conclusion

The administration of HBIG and HB vaccine successfully prevented vertical transmission, resulting in a high seroprotection rate.

Hepatitis B virus infection, associated factors, knowledge and vaccination status among household contacts of hepatitis B index cases in Mwanza, Tanzania

Objectives

To determine the prevalence of hepatitis B virus (HBV) infection, knowledge regarding HBV, vaccination status, and associated factors among household contacts of HBV index cases in Mwanza, Tanzania.

Methods

Between July and August 2023, a cross-sectional study involving 97 index cases and 402 household contacts was conducted. Data were collected using pre-tested structured questionnaire and blood samples were collected from household contacts for HBV surface antigen (HBsAg) testing.

Results

The prevalence of HBV among household contacts was 5.4% (95% confidence interval, 2.9-9.0) with a significantly high proportion observed in > 45 years (16.6%) and in males (9.9%). A total of 40.0% of the household contacts had completed the full HBV vaccination series. On multivariate analysis, being male was significantly associated with HBsAg positivity (odds ratio: 7.16, 95% confidence interval: 1.81-28.2, P = 0.005).

Conclusion

About one-tenth of adults' male household contacts were HBsAg positive. In addition, the majority of household contacts had poor to fair knowledge regarding HBV infection with more than half being unvaccinated against HBV. There is a need to enhance awareness and education regarding HBV infection among household contacts in Tanzania and other low- and middle-income countries.

Deep sequencing of hepatitis B surface antigen gene in the preserved umbilical cords in immunoprophylaxis failure against mother-to-child HBV transmission

BACKGROUND

Vaccine escape mutants (VEMs) are one of the causes of breakthrough infections in the mother-to-child transmission of hepatitis B virus (HBV). We hypothesized that VEMs existing as minor populations in the maternal blood are associated with breakthrough infections in children. We sought to determine whether VEMs exist as minor populations in the preserved umbilical cords of children with breakthrough infections.

CASE PRESENTATION

Two families (Family 1: three children, Family 2: two children) were enrolled. Despite immunoprophylaxis, a breakthrough infection occurred in two Family 1 children and two Family 2 children. Preserved umbilical cords, serum, and nails were used for the HBV DNA analysis. To detect VEMs, we performed direct and deep sequencing of hepatitis B surface antigen gene. The direct sequencing showed that there were no VEMs in the serum of the children or mother of Family 1 and family 2, but it identified a G145A mutant in the nails of the mother of Family 2. In Family 1, deep sequencing detected a T143S mutant as a minor population (1.7-2.0%) in the umbilical cords and serum of all three children and in the serum of the mother. A T126A mutant was also detected in the umbilical cord (9.2%) and serum (7.0%) of the first-born child of Family 1. In Family 2, the deep sequencing showed no VEMs in the umbilical cords, but it detected D144A (2.5%) and G145A (11.2%) mutants in the serum of the 2nd-born child.

CONCLUSIONS

VEMs were present as minor populations in the preserved umbilical cords of children with breakthrough infections. The VEMs did not become major populations after the breakthrough infections. The evolution of VEMs from a minor form to a major form might not be a prerequisite for breakthrough infections in mother-to-child transmission.

Medical and dental students' attitude and practice of prevention strategies against hepatitis B virus infection in a Nigerian university

Introduction

Medical and dental students are a high-risk group for hepatitis B virus (HBV) infection which is an occupational hazard for them and a leading cause of death globally. Prevention strategies include vaccination and observance of standard precaution. However, available reports claim utilization of the prevention strategies is low. This study evaluated the attitude of the students towards HBV vaccine and cross-infection practices.

Methods

This study was a cross-sectional study carried out at the College of Health Sciences, Obafemi Awolowo University, Nigeria. Using the convenience sampling method, anonymous self-administered questionnaires were distributed to the first 120 participants that volunteered to participate in the study. Data analysis was done using IBM's Statistical Package (SPSS) version 20 software. Statistical level of significance was set at p < 0.05.

Results

Over eighty percent (83.2%) of the participants had at least a dose of the HBV vaccine while 79.65% completed the three doses. Majority (94.7%) of the students that did not receive the vaccine cited their busy schedule as the reason for their failure to be vaccinated. Taking every patient as a contagious disease risk (86.5%), washing hands after contact with patients' body fluids (82.1%) and wearing gloves before touching mucous membranes and non-intact skin (74.1%) were the most practiced universal standard precaution items.

Conclusion

The uptake rate of HBV vaccination and practice of standard precaution among the students are commendable. However, there is need for improvement considering the level of HBV infection in Nigeria.