Vaccination against Hepatitis B: A Scoping Review

Prevention in Hepatology

The prevention of liver disease has improved significantly in the last few decades, to the point that it can now be considered a true success story. The wide variety of interventions, including comprehensive vaccination strategies, novel medications, lifestyle changes, and even preventive surgeries, have reduced the morbidity and mortality of chronic liver diseases. However, the prevalence of chronic liver diseases is increasing worldwide. Currently, fatty liver disease alone is estimated to be present in as much as 30% of the adult population. Furthermore, there is a trend towards increasing incidences of chronic hepatitis B, and a global lack of success in efforts to eliminate chronic hepatitis C. Thus, improving and efficiently rolling out existing and successful prevention strategies for chronic liver diseases will play an essential role in healthcare throughout the upcoming decades. In this review, we summarize the current options and concepts for preventing chronic liver diseases, highlight their limitations, and provide an outlook on probable future developments to improve awareness, integrated care, and the analysis of big data.

HBV Vaccines: Advances and Development

Hepatitis B virus (HBV) infection is a global public health problem that is closely related to liver cirrhosis and hepatocellular carcinoma (HCC). The prevalence of acute and chronic HBV infection, liver cirrhosis, and HCC has significantly decreased as a result of the introduction of universal HBV vaccination programs. The first hepatitis B vaccine approved was developed by purifying the hepatitis B surface antigen (HBsAg) from the plasma of asymptomatic HBsAg carriers. Subsequently, recombinant DNA technology led to the development of the recombinant hepatitis B vaccine. Although there are already several licensed vaccines available for HBV infection, continuous research is essential to develop even more effective vaccines. Prophylactic hepatitis B vaccination has been important in the prevention of hepatitis B because it has effectively produced protective immunity against hepatitis B viral infection. Prophylactic vaccines only need to provoke neutralizing antibodies directed against the HBV envelop proteins, whereas therapeutic vaccines are most likely needed to induce a comprehensive T cell response and thus, should include other HBV antigens, such as HBV core and polymerase. The existing vaccines have proven to be highly effective in preventing HBV infection, but ongoing research aims to improve their efficacy, duration of protection, and accessibility. The routine administration of the HBV vaccine is safe and well-tolerated worldwide. The purpose of this type of immunization is to trigger an immunological response in the host, which will halt HBV replication. The clinical efficacy and safety of the HBV vaccine are affected by a number of immunological and clinical factors. However, this success is now in jeopardy due to the breakthrough infections caused by HBV variants with mutations in the S gene, high viral loads, and virus-induced immunosuppression. In this review, we describe various types of available HBV vaccines, along with the recent progress in the ongoing battle to develop new vaccines against HBV.

Barriers and facilitators of integrated hepatitis B, C, and HIV screening among pregnant mothers and their newborns attending maternal and newborn clinics in Koboko District, Uganda: A qualitative inquiry of providers' perspective

Background

HIV and HBV remain significant public health challenges characterized by high prevalence, morbidity, and mortality, especially among women of reproductive age in Uganda. However, both HIV and HBV patients are managed in separate clinics with separate staff even though they all receive ART. Patients with HBV do not receive routine counselling and education, and there are limited resources for laboratory investigation coupled with a high loss to follow-up. This study set out to "assess barriers and facilitators of integrated viral hepatitis B C and HIV care model to optimize screening uptake among mothers and newborns at health facilities in Koboko District, west Nile sub-region, Uganda".

Methods

A cross-sectional grounded theory qualitative approach was employed in an institutional setting (HC IIIs). Data was audio recorded using a recording device during the key informant interviews and was transcribed after all interviews were conducted. Data was then analyzed using framework analysis.

Results

The following facilitated integration: High prevalence, and therefore burden of hepatitis B infection in West Nile region, team spirit by the health workers, reduced long waiting time, availability of medical products such as HBV and HCV test kits, integration of HBV and HIV into HMIS2 form and availability of support from implementing partners such as Infectious Dease Institute which offered mentorship and training on integration and support supervision.

Conclusion

Barriers to integration included; knowledge gap among health care workers, lack of transport for patients, language barriers during health education, inadequate human resources for health, stock-out of testing kits for HBV and HCV, lack of HMIS 2 column to capture HCV data, lack of funds to facilitate follow up of patients after referral for further investigation upon suspected cases of HBV and HCV. The study participants recommended; Promoting the integration of HBV, HCV, and HIV into routine health services; ensuring a constant supply of HBV, and HCV test kits to avoid stock-out; Engaging VHTs/Community health volunteers to support follow-up of patients and conducting health care workers performance reviews; addressing the issue of inadequate human resource; and finally dealing with misconceptions at community level about HBV and HCV diseases which hinder access to services.

Effectiveness of oral levamisole as an adjuvant to hepatitis B vaccination in healthcare workers non-responsive to previous vaccination: A randomized controlled trial

Background

Healthcare workers are at risk for HBV infection through percutaneous or mucosal contact with infected blood, body secretions, or blood products or via sharps injury. Hepatitis B vaccination, despite immunogenicity, may not induce a proper immune response in 5-10% of the general adult population. Increased immune response in healthcare providers that do not respond properly to conventional hepatitis B vaccination is an important health challenge. Therefore, the aim of the present study was to evaluate the effectiveness of hepatitis B vaccination plus oral levamisole as adjuvant in healthcare providers non-responsive to routine vaccination.

Materials and methods

The healthcare workers that were non-responsive to previous hepatitis B vaccination were enrolled in a double-blind randomized placebo-controlled clinical trial. The participants were then randomized to two groups including hepatitis B vaccination (as a three-dose series on a 0, 1, and 2-month schedule in the deltoid muscle) plus levamisole (levamisole group) and hepatitis B vaccination plus placebo (placebo group) at a 1:1 ratio. The outcome measure was the HBs antibody titer one month after receiving each dose as well as the seroprotection ratio. The side effects were also evaluated in all participants.

Results

In total, 22 subjects finished the trial (11 individual in per group). The median antibody titer one month after receiving the first and third doses increased more in the levamisole group compared to the placebo group but the difference was not significant (p ​= ​0.34, p ​= ​0.66, respectively).The seroprotection ratio after three doses was similarly high in both groups (90.9% in per group). Furthermore, the seroprotection ratio and median antibody titer had no significant correlation with age, sex, BMI, and history of smoking in intervention and control groups (p>0.05). No serious side effects were noted in both groups.

Conclusions

Re-vaccination can boost the immune response in healthcare professionals that were non-responsive to previous vaccination although the mean antibody titer was higher in the levamisole group.

Impact of coronavirus disease 2019 on prevention and elimination strategies for hepatitis B and hepatitis C

The coronavirus disease 2019 (COVID-19) pandemic has resulted in significant morbidity and mortality since its first case was discovered in December 2019. Since then, multiple countries have witnessed a healthcare system collapse due to the overwhelming demand for COVID-19 care. Drastic measures have been taken globally in order to curb the spread of the virus. However, those measures have led to the disruption of other aspects of healthcare, increasing the burden due to other medical conditions. We have also stepped back in achieving the ambitious goal set in place by World Health Organization to eliminate viral hepatitis as a public threat by 2030. Hepatitis B and C are chronic conditions with a significant worldwide burden, and COVID-19 has resulted in many hepatitis elimination programs slowing or stopping altogether. In this review, we elucidate the impact of the ongoing COVID-19 pandemic on the interventions targeted towards the elimination of hepatitis B virus and hepatitis C virus. Some of the salient features that we have covered in this review include hindrance to screening and diagnostic tests, neonatal vaccinations, the transmission dynamics affecting hepatitis B virus and hepatitis C virus, role of limited awareness, restrictions to treatment accessibility, and disparity in healthcare services. We have highlighted the major issues and provided recommendations in order to tackle those challenges.