Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and management.It delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive immunity.Viral factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are examined.Notably,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease progression.HBV reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is detailed.Management strategies,including anti-viral and immunomodulatory approaches,are critically analyzed.The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation.In conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation.With a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge base.The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient outcomes.The dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory approaches.The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

Prevalence of Children Vaccinated against Viral Hepatitis B in Brazzaville

Introduction: Viral hepatitis B (VHL) is a public health problem, particularly in sub-Sahara Africa. The aim of this study was to assess vaccination coverage against HBV in children in Brazzaville. Patients and Methods: This was a cross-sectional analytical study conducted in Brazzaville health centres from January to September 2019. It involved children aged between six months and six years who received a vaccination against HBV. Sampling was exhaustive and based on stratified sampling. Results: The overall prevalence of children vaccinated against HBV in Brazzaville was 96.2%. It was insufficient in the Talangai health district (79%). The pentavalent vaccine was administered to 97.7% of children, 85% of whom had received all three doses. The reasons for incomplete vaccination were parents’ ignorance of HVB (85.6%) and of vaccination (14.3%). Conclusion: Although the prevalence of vaccinated children is high in Brazzaville, it is still insufficient in some health districts, particularly Talangai, because parents are unaware of the disease and of vaccination. Pentavalent is the only vaccine available in the national vaccination programme, which is why an effective national vaccination policy needs to be put in place. .

Perception of Medical Students towards Hepatitis B Virus Infection and Hepatitis B Vaccination in a Private Tertiary Hospital in Jos North Local Government, Plateau State, Nigeria

Background: Prevention is one of the safe schemes against the high prevalence of viral Hepatitis. Negative perceptions or perceptions about the risks of hepatitis B among medical students and health care workers may influence the behavioral pattern and adoption of preventive measures against the virus and can affect the uptake of the Hepatitis B vaccine. This study assesses the perception of medical students towards Hepatitis B virus infection and Hepatitis B Vaccination in a Private Tertiary Hospital in Jos North Local Government, Plateau State, Nigeria. Methods: This was a descriptive cross-sectional study done in August 2021 among 236 clinical medical students using a multistage sampling technique. Data was collected using an interviewer-administered structured questionnaire and analysed using the IBM SPSS 28 (Statistical Package for the Social Sciences). Ethical approval was granted by Bingham University Teaching Hospital, Ethics Committee, Jos, Plateau State. Results: Two-thirds of respondents were of the opinion that they are at risk of contracting HBV. Half were of the opinion that the risk is very much while a third believed the risk is moderate. Among those who think they are not at risk of contracting HBV, the majority felt so because they are vaccinated while 10.3% believe that they are safe. 43.2% of respondents think that HBV Vaccine is very effective in preventing HBV infection while 39.8% think it is slightly effective, and 7.6% think it is not effective. Almost all respondents, 99.2% are of the opinion that HBV Vaccination is important for students while 0.8% think it is not important. The majority of the respondents at 95.8% were willing to be screened for HBV. The majority (85.6%) of respondents are willing to pay for HBV Vaccine as against 14.4% of respondents who are not willing to pay. Conclusion: Summarily, 21 (8.9%) of the students had a negative perception of Hepatitis B Vaccination, and 215 (91.1%) had a positive perception of Hepatitis B Vaccination. Perception-sustaining events like seminars, workshops, road shows, and campaigns should be organized among students and health workers.

Hepatitis B Vaccination in Medical and Dental Students: A Cross-Sectional Study

Background: Medical and dental students are at risk of Hepatitis B Virus (HBV) infection. The study aimed to assess the vaccination status against Hepatitis B Virus of students in clinical and non-clinical years of a private medical and dental college, and their knowledge, attitude, and awareness about the subject. Methods: A cross-sectional study was conducted using a pretested, self-administered questionnaire among 203 medical and dental students of CMH Lahore Medical College and Institute of Dentistry (CMH LMC & IOD) in Lahore, Pakistan. Participants were evaluated for their knowledge and vaccination status against Hepatitis B Virus. Students were considered to be fully vaccinated (recipients of 3 doses), partially vaccinated (recipients of 1 or 2 doses), and unvaccinated. Comparisons were made between students of clinical and non-clinical years. Data was entered and analysed using Statistical Package for the Social Sciences (SPSS) version 23. Results: Only 66% (n = 134) of the 203 participants had ever received a Hepatitis B Virus vaccine out of which a meagre 17.2% (n = 35) were fully vaccinated. No significant difference was found in vaccine uptake between students of clinical and non-clinical years (p-value = 0.181) despite significant differences seen in the knowledge of vaccination schedule (p-value = 0.001), the prevalence of needle-stick injuries (p-value = 0.001), and knowledge of protocols to be followed after a needle-stick injury (p-value = 0.001). Conclusion: Our study found that a large proportion of the student population is vulnerable to HBV infection. There is a need to create awareness regarding the subject to increase vaccine uptake. HBV vaccination should be offered to all currently enrolled students and be made mandatory at the time of admission in the future.

Hepatitis B vaccination status and associated factors among health science students

Objective:To evaluate hepatitis B virus(HBV)vaccine coverage and its associated factors among health science students in Vietnam.Methods:This cross-sectional study involving 459 health science students at Tra Vinh University was conducted between April and June 2022.Data were collected using a structured questionnaire with items on sociodemographic characteristics,knowledge and attitude about HBV,and vaccination status.A multivariable logistic regression model was used to explore the factors associated with vaccination status.Results:The majority of participants were female(65.8%)and enrolled at the medical school(56.2%).A total of 30.3%participants received the full dose of the HBV vaccine.The percentages of participants with sufficient knowledge and positive attitudes toward HBV infection were 75.2%and 43.4%,respectively.Vaccination was 11.8 times higher in sixth-year medical students than any healthcare student in their first-year[adjusted odds ratio(aOR)11.8,95%CI 3.1-45.1,P<0.001],and the coverage was also significant higher in those who had sufficient knowledge(aOR 2.0,95%CI 1.1-3.9,P<0.05)and positive attitudes(aOR 3.0,95%CI 1.9-4.8,P<0.05)than in their counterparts.Conclusions:The majority of students were not fully vaccinated against HBV,indicating they were vulnerable to the disease.Administrators and authorities should reinforce health education messages aimed at encouraging all students to get vaccinated with the HBV vaccine,enhance their awareness and knowledge of HBV,and improve attitudes toward HBV infection prevention.

Factors Associated with Antibody Levels among Children Aged 15 to 59 Months Vaccinated against Hepatitis B during the Expanded Program on Immunization in Cameroon

Background: the hepatitis B virus infection remains a major public health problem worldwide. It can lead to a liver cirrhosis and/or hepatocellular carcinoma. The World Health Organisation (WHO) has recommended the implementation of generalised vaccination programs against hepatitis B. In Cameroon, this vaccine was introduced in the expanded program on immunization (EPI) in 2005, but few studies have assessed the immune response. Objective: the general objective of this study was to identify factors associated with antibody levels among children aged from 15 to 59 months vaccinated against hepatitis B during the EPI in Cameroon. Method: this was a cross-sectional study carried out from December 2021 to June 2022 in a paediatric centre of Yaoundé (Cameroon). We analysed the antibody level in children vaccinated against hepatitis B within the framework of the EPI. We enrolled children who had received a series of 3 intramuscular doses of hepatitis B vaccine at 6, 10 and 14 weeks after birth. Some children could receive a 4th booster dose between 12 months. The antibody level was assessed by measuring the anti-HBs in such children, aged 15 - 59 months. A good immunization was defined as a serum level of anti-HBs antibody level above 100 IU/mL;a poor immunization, for an anti-HBs antibody level between 10 and 100 IU/mL;and a non-immunization, for an anti-HBs antibody level < 10 IU/mL. Association between explored factors and poor or non-immunization was evaluated through the Chi square test. The significance threshold was defined at p < 0.05. Results: sixty subjects were included in the study with a slight female majority: 31 cases (52%). The average age was 38.5 ± 15.7 months (range 15 - 59 months). We found 32 (53%) cases of good immunization;21 (35%) of poor immunization;and 7 children (12%) with a non-immunization. The only factor associated with poor or non-immunization was the age between 37 - 59 months (p = 0.016). Conclusion: Anti HBs Antibody levels in children vaccinated against hepatitis B virus were globally satisfactory in our series. Results show an association between low antibody levels with older age (over 36 months), suggesting a circulating antibodies levels decrease over time, yet deemed protecting until 59 months.

Knowledge, Attitudes, and Practices (KAP) Regarding Hepatitis B Vaccination among Healthcare Workers in Mongolia

Background: Mongolia is no exception and experiencing the burden of HBV among the population. In the last decade, the prevalence of HBV among the relatively healthy population of Mongolia has ranged between 11.8 percent and 10.6 percent, and acute cases are between 1.7 and 1.1 per 10,000 people. We aimed to determine healthcare workers (HCWs) knowledge, attitude, and practices regarding HBV prevention compared to vaccination coverage. Methods: This cross-sectional study was conducted among HCWs from the selected sites through multi-stage sampling. The study involved 1135 HCWs, including medical doctors, nurses, clinicians in both surgical and medical specialties, laboratory technicians, and other staff working in all departments from primary and referral levels in 36 healthcare facilities in two urban and four rural provinces of Mongolia. Participants who consented to the study completed a standardized self-administered questionnaire between July and Dec 2019. Results: Most participants (82.0%) were born before 1992 or before starting a birth vaccination against HBV in Mongolia. The mean age of the participants was 38 years and the participants’ median employment year in the health sector was seven years. Most participants were medical doctors (29.1%) and nurses (28.0%). Five questions explored HCWs’ knowledge about hepatitis B virus infection and prevention, and the correct response ranged between 15.6% and 95.4%. 2.8% of the respondents answered five questions correctly. Men, those with higher levels of education, those over the age of 30, soum family health center HCWs, and doctors and senior medical professionals answered many questions correctly, which is statistically significant. 98.9% of respondents believe that HCWs should vaccinate against HBV. The younger the age (%), management professionals, and service staff are confident in vaccines. A significant difference between age groups, perception of HBV infection, and formal attendance to the official training positively relate to vaccination coverage. Specially survey respondents who knew about the adverse effects of overdosing, learning about total doses of the vaccine, and the effectiveness of the hepatitis B vaccine were more tent to have full doses of the HBV vaccine. Knowledge and working conditions are increasing factors in receiving full doses of the HVB vaccine. Conclusion: The overall knowledge of HBV and its vaccination is fair among the HCWs;however, there is a need to intensify the training on some of the details and increase the training frequency at the workplace. Attitude and practice on infection protection and vaccination are still essential to be promoted among the HCWs. The low level of vaccination coverage is relevant to the level of KAP among the HCWs of the country.

HBsAg, HBcAg, and combined HBsAg/HBcAg-based therapeutic vaccines in treating chronic hepatitis B virus infection

BACKGROUND: As the host immunity is diminished in patients with chronic hepatitis B (CHB), different approaches have been used to up-regulate their immune responses to produce therapeutic effects. But, cytokines, growth factors and polyclonal immune modulators could not exhibit sufficient therapeutic effects in these patients. Immune therapy with HBV-related antigens (vaccine therapy) has been used in CHB patients. But there is a paucity of information about the design of HBV antigen-based immune therapy in these patients. DATA SOURCE: Preclinical and clinical studies on immune therapy with HBsAg-based vaccine, HBcAg and combination of HBsAg/HBcAg-based vaccines have been discussed. RESULTS: HBsAg-based prophylactic vaccine was used as an immune therapeutic agent in CHB patients; however, monotherapy with HBsAg-based immune therapy could not lead to sustained control of HBV replication and/or liver damages. HBsAg-based vaccine was used as a combination therapy with cytokines, growth factors, and antiviral drugs. HBsAg-based vaccine was also used for cell-based therapy. However, satisfactory therapeutic effects of HBsAg-based vaccine could not be documented in CHB patients. In the mean time, evidences have supported that HBcAg-specific immunity is endowed with antiviral and liver protecting capacities in CHB patients. Recent data concentrate on the clinical use of combined HBsAg- and HBcAg-based vaccines in CHB patients.CONCLUSION: Antigen-based immune therapy with HBV- related antigens may be an alternative method for the treatment of CHB patients but proper designs of antigens, types of adjuvants, dose of vaccinations, and routes of administration need further analyses for the development of an effective regimen of immune therapy against HBV.

Nucleic acid vaccines: A taboo broken and prospect for a hepatitis B virus cure

Although a prophylactic vaccine is available,hepatitis B virus(HBV)remains a major cause of liver-related morbidity and mortality.Current treatment options are improving clinical outcomes in chronic hepatitis B;however,true functional cure is currently the exception rather than the rule.Nucleic acid vaccines are among the emerging immunotherapies that aim to restore weakened immune function in chronically infected hosts.DNA vaccines in particular have shown promising results in vivo by reducing viral replication,breaking immune tolerance in a sustained manner,or even decimating the intranuclear covalently closed circular DNA reservoir,the hallmark of HBV treatment.Although DNA vaccines encoding surface antigens administered by conventional injection elicit HBVspecific T cell responses in humans,initial clinical trials failed to demonstrate additional therapeutic benefit when administered with nucleos(t)ide analogs.In an attempt to improve vaccine immunogenicity,several techniques have been used,including codon/promoter optimization,coadministration of cytokine adjuvants,plasmids engineered to express multiple HBV epitopes,or combinations with other immunomodulators.DNA vaccine delivery by electroporation is among the most efficient strategies to enhance the production of plasmid-derived antigens to stimulate a potent cellular and humoral anti-HBV response.Preliminary results suggest that DNA vaccination via electroporation efficiently invigorates both arms of adaptive immunity and suppresses serum HBV DNA.In contrast,the study of mRNA-based vaccines is limited to a few in vitro experiments in this area.Further studies are needed to clarify the prospects of nucleic acid vaccines for HBV cure.

Relationship between T-lymphocyte cytokine levels and sero-response to hepatitis B vaccines

AIM: To investigate the cellular defects by analyzing the (Th1/Th2) cytokine levels in vaccine responders and non-responders. METHODS: Peripheral blood mononuclear cell (PBMC) from responders and non-responders were stimulated with or with out recombinant HBsAg or PHA. Broad spectrum of cytokines viz (Th1) IFN-γ, IL-2, TNF-α, IL-12 and (Th2) IL-10, IL-4 were measured after in vitro stimulation with recombinant HBsAg and were compared with respective antibody titers. RESULTS: A significant decrease (P = 0.001) in Th1 and Th2 cytokines namely, IL-2, INF-γ, TNF-α and IL-10in non-responders was observed. The level of IL-4 was not significant between the three groups. Furthermore, despite a strong Th1 and Th2 cytokine response, the level of IL-12 was elevated in high-responders compared to other groups (P = 0.001) and demonstrated a positive correlation with anti-HBs titers and Th1 cytokine response. CONCLUSION: Our findings suggest that unrespon-siveness to recombinant hepatitis B vaccines (rHB) is multifactorial, including specific failure of antigen presentation or the lack of both T helper Th1 and Th2 response.

A Study on Long-term Efficacy and Immunologic Persistence of Hepatitis B Plasma Vaccine Made in China

In order to demonstrate the long term protective efficacy and immunologic persistence of domestically made hepatitis B plasma derived vaccine, 371 children had been followed up for 5 to 8 years after primary vaccination (10 μg×3). The results showed that the positive rate of antibody to hepatitis B surface antigen (anti HBs) in 371 subjects was 77.6% and the geometric mean titre (GMT) of anti HBs was 47.32 IU/L. The anti HBs positive rates in the subjects who had been vaccined for five, six, seven and eight years remained 83.91%, 73.68%, 81.25% and 72.24%, respectively, while the GMTs were 59.53, 43.64, 42.21 and 46.20 IU/L, respectively. The protective efficacy rate of hepatitis B vaccine was 94.26% if both HBsAg and anti HBc were considered as infective indicators, and 88.28%, if only HBsAg positive cases were taken into account. The study indicated that the domestically made hepatitis B vaccine could provide at least 5 to 8 years protection against hepatitis B infection.

Optimal Control of Hepatitis B in a sub-Saharan African rural area

In this paper,we ameliorate the model proposed in[13],by incorporating the influence of hepatitis B e antigen(HBeAg)status of mothers on vertical transmission.We use the improved model to fit reported HBV new infections in the Zhejiang Province of China.Also to predict the course of the Hepatitis B(HBV)infection in this Chinese area,and in Tokombere,located in sub-Saharan Africa(SSA).Furthermore,we apply optimal control techniques in view to re-examine the effects of the newborn vaccination,the universal vaccination and the treatment of chronic carriers in preventing the HBV infection.Simulation results show that treatment slightly steps in the optimal strategy,while immunisation is an effective measure.On the other hand,they indicate that the control measures and immunization programs implemented in Zhejiang Province are effective.Besides,they suggest that in SSA,a package of several policies centred on birth dose vaccination should be implemented.

DNA-based vaccination induces humoral and cellular immune responses against hepatitis B virus surface antigen in mice without activation of Cmyc

AIM To develop a safe and effective DNAvaccine for inducing humoral and cellularimmunological responses against hepatitis Bvirus surface antigen(HBsAg).METHODS BALB/c mice were inoculated withNV-HB/s,a recombinant plasmid that had beeninserted S gene of hepatitis B virus genome andcould express HBsAg in eukaryotes.HBsAgexpression was measured by ABC immunohis-tochemical assay,generation of anti-HBs byELISA and cytotoxic T lymphocyte(CTL),byMTT method,existence of vaccine DNA bySouthern blot hybridization and activation ofoncogene C-myc by in situ hybridization,RESULTS With NV-HB/s vaccination byintramuscular injection,anti-HBs was initiallypositive 2 weeks after inoculation while all micetested were HBsAg positive in the muscles.Thetiters and seroconversion rate of anti-HBs weresteadily increasing as time went on and weredose-dependent.All the mice inoculated with100 μg NV-HB/s were anti-HBs positive onemonth after inoculation,the titer was 1:1024 ormore.The humoral immune response was similarinduced by either intramuscular or intradermalinjection.CTL activities were much stronger(45.26%)in NV-HB/s DNA immunized mice as compared with those(only 6%)in plasma-derived HBsAg vaccine immunized mice.Twomonths after inoculation,all muscle sampleswere positive by Southern-blot hybridization forNV.HB/s DNA detection,but decreased to 25%and all were undetectable by in situhybridization after 6 months.No oncogene C-myc activation was found in the muscle ofinoculation site.CONCLUSION NV-HB/s could generatehumoral and cellular immunological responsesagainst HBsAg that had been safely expressed insitu by NV-HB/s vaccination.

Humoral and cellular immunogenecity of DNA vaccine based on hepatitis B core gene in rhesus monkeys

INTRODUCTIONHepatitis B virus (HBV) is the most commonetiologic agent for infectious liver diseases. It isestimated that there are more than 250 millionchronic HBV carriersin the world today and thereis a significant association among persistentinfection, liver cirrhosis and hepatocellularcarcinoma[1-3].

Long-term efectiveness of infancy low-dose hepatitis B vaccine immunization in Zhuang minority area in China

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A 12-year cohort study on the efficacy of plasmaderived hepatitis B vaccine in rural newborns

AIM To understand the anti-HBs persistenceand the long-term preventive efficacy in ruralnewborns after vaccination with plasma-derivedhepatitis B vaccine.METHODS In the time of expanded program onimmunization(EPI),the newborns werevaccinated with 10μg×3 doses of hepatitis Bvaccine and 762 newborns who were HBsAgnegative after primary immunization wereselected for cohort observation from 1986 to1998.Their serum samples were detectedqualitatively and quantitatively for hepatitis Binfecting markers,including HBsAg,anti-HBsand anti-HBc by SPRIA Kits.The annual HBsAgpositive conversion rate was counted by life-table method.RESULTS①The anti-HBs positive rate was94.44% for the babies born to HBsAg negativemothers and 84.21% for those born to HBsAgpositive mothers in the 1st year afterimmunization,and dropped to 51.31% and52.50% in the 12th year respectively.GMT valuewas dropped from 31.62 to 3.13 and 23.99 to 3.65in the 2nd to the 12th year respectively.Therewas a marked drop in GMT at the 3rd to the 5thyear,and in anti-HBs positive rate at the 9th tothe 10th year.②In the period of 12 yearsobservation,the person-year HBsAg positive conversion rates were 0.12%(5/4150.0)innewborns born to HBsAg negative mothers and0.20%(1/508.0)in those born to HBsAgpositive mothers,and none of the HBsAgpositive converted children became HBsAgchronic carriers.Compared with the baselinebefore immunization,the protective rates were97.19% and 95.32% respectively.CONCLUSION The protective efficacy ofplasma-derived hepatitis B vaccine persisted atleast 12 years,and a booster dose seems notnecessary within at least 12 years after theprimary three-doses immunization to newbornsborn to HBsAg negative mothers.

Persistence of hepatitis B vaccine immune protection and response to hepatitis B booster immunization

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Hepatitis B vaccine by intradermal route in non responder patients:An update

Vaccination is the main prophylactic measure to reduce the mortality caused by hepatitis B virus(HBV)infection in healthy subjects since the immune response to hepatitis B recombinant vaccination occurs in over 90%of general population.Individuals who develop an antiHBs titer less than 10 mIU/mL after primary vaccination cycle are defined"no responders".Many factors could cause a non response to the HBV vaccination,such as administration of the vaccine in buttocks,impaired vaccine storage conditions,drug abuse,smoking,infections and obesity.Moreover there are some diseases,like chronic kidney disease,human immunodeficiency virus infection,chronic liver disease,celiac disease,thalassaemia,typeⅠdiabetes mellitus,down’s syndrome and other forms of mental retardation that are characterized by a poorer response to HBV vaccination than healthy subjects.To date it is still unclear how to treat this group of patients at high risk of hepatitis B infection.Recent studies seem to indicate that the administration of HBV recombinant vaccine by the intradermal route is very effective and could represent a more useful strategy than intramuscular route.This review focuses on the use of anti hepatitis B vaccine by intradermal route as alternative to conventional intramuscular vaccine in all non responder patients.A comprehensive review of the literature using PubMed database,with appropriate terms,was undertaken for articles in English published since 1983.The literature search was undertaken in September 2013.

Long-term eficacy of plasma-derived hepatitis B vaccine among Chinese children:a 12-year folow-up study

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