Hepatitis B Virus (HBV) infection is one of the major causes of morbidity, mortality and healthcare expenditure in India. There are no Indian consensus guidelines on prevention, diagnosis and management of HBV infection. The Indian National Association for Study of the Liver (INASL) set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for diagnosis and management of HBV infection, relevant to disease patterns and clinical practices in India. The taskforce first identified contentious issues on various aspects of HBV management, which were allotted to individual members of the taskforce who reviewed them in detail. A 2-day round table discussion was held on 11th and 12th February 2017 at Port Blair, Andaman & Nicobar Islands, to discuss, debate, and finalize the consensus statements. The members of the taskforce reviewed and discussed the existing literature threadbare at this meeting and formulated the \'INASL position statements\' on each of the issues. The evidence and recommendations in these guidelines have been graded according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) system with minor modifications. The strength of recommendations (strong: 1, weak: 2) thus reflects the quality (grade) of underlying evidence (A, B, C, D). We present here the INASL position statements on prevention, diagnosis and management of HBV in India.

OBJECTIVE: An extracellular vesicle (EV) is a nanovesicle that shuttles proteins, nucleic acids, and lipids, thereby influencing cell behavior. A recent crop of reports have shown that EVs are involved in infectious biology, influencing host immunity and playing a role in the viral life cycle. In the present work, we investigated the EV-mediated transmission of hepatitis B virus (HBV) infection.
METHODS: We investigated the EV-mediated transmission of HBV infection by using a HBV infectious culture system that uses primary human hepatocytes derived from humanized chimeric mice (PXB-cells). Purified EVs were isolated by ultracentrifugation. To analyze the EVs and virions, we used stimulated emission depletion microscopy.
RESULTS: Purified EVs from HBV-infected PXB-cells were shown to contain HBV DNA and to be capable of transmitting HBV DNA to naive PXB-cells. These HBV-DNA-transmitting EVs were shown to be generated through a ceramide-triggered EV production pathway. Furthermore, we showed that these HBV-DNA-transmitting EVs were resistant to antibody neutralization; stimulated emission depletion microscopy showed that EVs lacked hepatitis B surface antigen, the target of neutralizing antibodies.
CONCLUSIONS: These findings suggest that EVs harbor a DNA cargo capable of transmitting viral DNA into hepatocytes during HBV infection, representing an additional antibody-neutralization-resistant route of HBV infection.

The immune system becomes less effective with age, and older age is associated with an increased susceptibility to diseases and reduced responses to vaccination. Furthermore, some adult populations, such as those with diabetes mellitus, are at increased risk of acute hepatitis B virus (HBV) infection. Decreasing responses to vaccination with advanced age have been described, but it is not known at what age immunogenicity starts to reduce, or until what age immunogenicity remains acceptable (for example ≥ 80% seroprotection post-vaccination). We characterized the relationship between age and seroprotection rate induced by recombinant HBV vaccination by conducting a pooled analysis of clinical trial data. Healthy adults aged ≥ 20 y who had been vaccinated with 20 μg HBV vaccine (Engerix™ B, GSK Vaccines, Belgium) in a 0, 1, 6 months schedule in 11 studies since 1996 were included. The observed seroprotection rate, defined as an anti-HBV surface antigen antibody concentration ≥ 10 mIU/ml was 94.5% in the whole population (N = 2,620, Total vaccinated cohort), ranging from 98.6% in adults vaccinated at age 20-24 years, to 64.8% in those vaccinated at age ≥ 65 y A model on seroprotection rates showed a statistically significant decrease with age, and predicted that the anti-HBs seroprotection rate remains ≥ 90% up to 49 y of age and ≥ 80% up to 60 y of age. Individuals at risk of HBV infection should be vaccinated as early in life as possible to improve the likelihood of achieving seroprotection. Additional studies are needed to identify whether unvaccinated individuals older than 60 y would benefit from regimens that include additional or higher vaccine doses.

OBJECTIVE: The aim of the study was to estimate long-term cost‑effectiveness of a hepatitis B vaccination catch-up program among children born between 1994 and 2001 (when they were 8‑15 y old) in Shandong province, China, to provide information for nationwide evaluation and future policy making.
METHODS: We determined the cost-effectiveness of the catch-up program compared with the status quo (no catch-up program). We combined a Decision Tree model and a Markov model to simulate vaccination and clinical progression after hepatitis B virus (HBV) infection. Parameters in the models were from the literature, a field survey, program files, and the National Notifiable Disease Reporting System (NNDRS). The incremental cost‑effectiveness ratio (ICER) was used to compare the 2 alternative strategies. One-way sensitivity analysis, 2-way sensitivity analysis, and probability sensitivity analysis were used to assess parameter uncertainties.
RESULTS: The catch-up program was dominant compared with the status quo. Using a total of 5.53 million doses of vaccines, the catch-up program could prevent 21,865 cases of symptomatic acute hepatitis B, 3,088 carrier states with positive hepatitis B surface antigen (HBsAg), and 812 deaths due to HBV infection. The catch-up program could add 28,888 quality-adjusted life years (QALYs) and save $192.01 million in the targeted population in the future. The models were robust, considering parameter uncertainties.
CONCLUSIONS: The catch-up program in Shandong province among children born between 1994 and 2001 was \'very cost-saving.\' It could save life years and reduce total future costs. Our study supported the desirability and impact of such a catch-up program throughout China.