anti-HBs Response Research Articles

Incidences of new hepatitis B infection and anti-hepatitis B core-negative occult hepatitis B infection among Japanese blood donors in relation to anti-hepatitis B surface antigen levels.

A transfusion-transmitted hepatitis B virus (HBV) infection caused by blood only positive for anti-hepatitis B surface antigen (anti-HBs) was reported. Occult HBV infection (OBI) with sole anti-HBs among blood donors is an issue. The incidence of HBV infection among repeat blood donors was investigated with a detailed HBV infection phase, focusing on the influence of anti-HBs level. This study followed 3 435 653 donors for HBV DNA conversion over 4 years and 9 months. Infection phase was determined based on marker changes over DNA conversion. This study identified 115 hepatitis B surface antigen (HBsAg) conversions, 72 DNA-only conversions, and 15 DNA plus anti-hepatitis B core (anti-HBc) conversions among donors all negative for HBV DNA, HBsAg, and anti-HBc. Total incidence was 2.38/100 000 person-years (PY). None of these 202 new HBV infections arose in the group with anti-HBs titer ≥ 10 mIU/mL. In total, 30 anti-HBc-negative OBIs were identified (incidence; 0.35/100 000 PY); 7 showed typical secondary anti-HBs response, and 23 showed stable anti-HBc and anti-HBs levels at DNA conversion. The HBV infection-protective ability of anti-HBs ≥ 10 mIU/mL was reinforced. In addition to new infections, the blood donor population includes anti-HBc-positive- and negative OBI with immune reactions or abortive HBV infection.

Blood HBV DNA in newborns from HBsAg-positive mothers might be predictive of immunization response

Background: In Ivory Coast, as in the rest of sub Saharan Africa, despite the introduction of anti-hepatitis B vaccine, toddlers and children remain a segment of the population frequently infected with Hepatitis B Virus (HBV). The conditions of early HBV transmission, and notably the materno-fetal route remain summarily documented in sub Saharan Africa. Methods: From June to November 2018, we analyzed the socio-demographical, serological, and viral features related to HBV transmission in expectant mothers and their newborns who came for delivery at the CHU Cocody Abidjan. Results: Out of 1628 contacted expectant mothers, a subset of 508 accepted to participate to the study, including 163 who were positive for HBsAg. All 56 mothers who transmitted either HBsAg or HBV DNA to their babies were presenting HBV DNA loads >5.0 log10 IU/mL Remarkably, fates of newborns either positive for HBsAg or HBV DNA who completed immune-prophylaxis were drastically different at 9-12 months. While a majority (90%) of HBsAg (+)-only babies became anti-HBs (+), 62.5% DNA-positive newborns failed to mount a proper anti-HBs response. Overall, 10.7% of newborns with at least one positive HBV marker at birth develop a bona fide chronic infection at 9 months. Conclusions: In Ivory Coast, pregnant women presenting HBV DNA loads above 5.0Log10 IU/mL are at risk of maternofetal transmission. Presence of HBV DNA in the blood of newborns represents a better predictor of anti-HBV immunization failure than HBsAg presence. An adaptation of immunization procedures with a passive immune prophylaxis targeting specifically newborns at risk should be urgently considered.

Protective Anti-HBs Antibodies and Response to a Booster Dose in Medical Students Vaccinated at Childhood.

The immune system in humans is regulated by the circadian rhythm. Published studies have reported that the time of vaccination is associated with the immune response to vaccine for some pathogens. Our study aimed to evaluate the association between time of dose administration of challenge HBV vaccine and seroconversion for anti-HBs in medical students vaccinated at birth who were found to be unprotected at pre-training screening. Humoral protection for HBV was assessed in 885 medical students vaccinated during childhood. In total, 359 (41.0%) of them showed anti-HBs titer < 10 UI/mL and received a challenge dose of HBV vaccine followed by post-vaccination screening 30-60 days later. The challenge dose elicited a protective immune response (anti-HBs IgG titer > 10 UI/mL) in 295 (83.8%) individuals. Seroconversion was significantly associated with female gender and time of vaccination after controlling for age group and nationality at logistic regression analysis. Students who received the booster dose in the morning had a higher response rate than those who received the vaccine in the afternoon (OR 1.93; 95% C.I. 1.047-3.56: p < 0.05). This finding suggests that morning administration of the HBV booster may result in a better immune response in susceptible individuals.

Hepatitis B vaccine delivered by microneedle patch: Immunogenicity in mice and rhesus macaques.

Vaccination against hepatitis B using a dissolving microneedle patch (dMNP) could increase access to the birth dose by reducing expertise needed for vaccine administration, refrigerated storage, and safe disposal of biohazardous sharps waste. In this study, we developed a dMNP to administer hepatitis B surface antigen (HBsAg) adjuvant-free monovalent vaccine (AFV) at doses of 5µg, 10µg, and 20µg, and compared its immunogenicity to vaccination with 10µg of standard monovalent HBsAg delivered by intramuscular (IM) injection either in an AFV format or as aluminum-adjuvanted vaccine (AAV). Vaccination was performed on a three dose schedule of 0, 3, and 9weeks in mice and 0, 4, and 24weeks in rhesus macaques. Vaccination by dMNP induced protective levels of anti-HBs antibody responses (≥10 mIU/ml) in mice and rhesus macaques at all three HBsAg doses studied. HBsAg delivered by dMNP induced higher anti-HBsAg antibody (anti-HBs) responses than the 10µg IM AFV, but lower responses than 10µg IM AAV, in mice and rhesus macaques. HBsAg-specific CD4+ and CD8+ T cell responses were detected in all vaccine groups. Furthermore, we analyzed differential gene expression profiles related to each vaccine delivery group and found that tissue stress, T cell receptor signaling, and NFκB signaling pathways were activated in all groups. These results suggest that HBsAg delivered by dMNP, IM AFV, and IM AAV have similar signaling pathways to induce innate and adaptive immune responses. We further demonstrated that dMNP was stable at room temperature (20°C-25°C) for 6months, maintaining 67±6 % HBsAg potency. This study provides evidence that delivery of 10µg (birth dose) AFV by dMNP induced protective levels of antibody responses in mice and rhesus macaques. The dMNPs developed in this study could be used to improve hepatitis B birth dose vaccination coverage levels in resource limited regions to achieve and maintain hepatitis B elimination.

Impaired long-term anti-HBs responses in choronic hepatitis C patients: Results from a five-year follow-up study with healthy control

ABSTRACT Although hepatitis B virus (HBV) vaccination is recommended for hepatitis C virus (HCV)-infected individuals to avoid HBV superinfection, the persistence of their humoral and cell-mediated immunity responses to HBV vaccination is still under investigation. Patients with chronic hepatitis C (CHC) and matched healthy controls, who completed three doses of hepatitis B vaccine (HepB) in 2014, were followed up five years later. One booster dose of HepB was given to those with antibody against hepatitis B surface antigen (anti-HBs) lower than 10mIU/mL. Anti-HBs was tested at follow-up and on the 14th day after the booster dose, as well as HBsAg specific spot-forming cells of interferon γ and interleukin (IL) 2, 4, 5, and 6. At five years, only 56.58% of the CHC patients had sero-protective titers (≥10mIU/mL) of anti-HBs, compared to 70.83% in the controls (P < .05). Similarly, the geometric mean concentration (GMC) of anti-HBs in CHC patients was significantly lower than that in controls (16.95 vs 37.34 mIU/mL, P < .05). After the booster, both GMC and the rate of anamnestic response increased to a very high level in the two groups and the difference between them disappeared (P > .05). Multivariable analysis showed that HCV infection was an independent predictor factor to anti-HBs level at follow-up. HBsAg specific IL-6 was stronger in the CHC patients compared to the controls (P < .05). The data indicate that the durability of protective anti-HBs is poorer in CHC patients compared to healthy individuals, and impaired long-term anti-HBs responses might be associated with the increased HBsAg specific IL-6 responses.

Anti-HBc-nonreactive occult hepatitis B infections with HBV genotypes B and C in vaccinated immunocompetent adults.

Absence of anti-HBc reactivity with detectable anti-HBs was observed in blood donors with occult hepatitis B virus (HBV) infection (OBI). The prevalence and mechanisms underlying this uncommon condition were investigated over time in Chinese blood donors with OBI. Isolated anti-HBs OBI status was identified from 466,911 donors from Dalian, China, and monitored in follow-up (range: 2.6-84.3months). HBV vaccination status was documented, and infecting viral strains were characterized. Of 451 confirmed OBIs (1:1035), 43 (9.5%; 1:10,858) had isolated anti-HBs as only serological marker. Isolated anti-HBs OBIs differed from anti-HBc-reactive OBIs by significantly younger age (median 24 years), higher HBV DNA (median: 20 IU/ml) and anti-HBs (median 60.5IU/L) levels, paucity of mutations in HBV Core and S proteins, and high vaccination rate (72%). Vaccinated isolated anti-HBs OBIs (n=31) differed from unvaccinated (n=11) by significantly younger age (22 vs 38 years), higher anti-HBs level at index (48% vs 9% with anti-HBs >100 IU/L) and higher frequency of anti-HBs immune response (44% vs 20%). Of 15 vaccinated and 5 unvaccinated OBIs follow-up, 65% (8 vaccinated and 5 unvaccinated) became HBV DNA negative suggesting aborted recent infection, while 35% (7 vaccinated) had low persistent viraemia 2 to 65 months post index. In conclusion, isolated anti-HBs OBI in Chinese blood donors appears associated with young, vaccinated, adults exposed to HBV who predominantly develop low level aborted infection revealed by transient HBV DNA and immune anti-HBs response. However, a subset of individuals still experienced low but persistent viral replication whose clinical outcome remains uncertain.

Antibody response to an accelerated course of Hepatitis B vaccination.

There are several courses with different dosing intervals for Hepatitis B vaccination. This independent study is looking at the antibody response after three doses of the accelerated course. The primary aim of the study was to examine data available at an Occupational Health Service for the antibody response to one or if nonresponsive, two accelerated Hepatitis B courses. A secondary aim is to determine if there is a difference in response for different sex and age groups. This is a retrospective anonymous and blinded study looking at the antibody response in 1032 healthcare personnel given the accelerated course of the Hepatitis B vaccine over a period of over 6 years. An anti-Hbs response 4 months after the start of the vaccination of >10 IU/ml was taken as indicative of a response. After one course, 93% of the healthcare personnel developed antibody levels thought to confer immunity. After two courses, nearly 99% of the healthcare personnel had developed an adequate immune response. The response was better in females and <40 years old, a difference that was statistically significant for those aged <40. The accelerated course confers high levels of immunity after 4 months and this supports the current practice of offering the accelerated dose to UK healthcare personnel who can be at immediate and higher risk of infection. Though some groups are less responsive, all groups mount a good response so all those at risk should be encouraged to have this vaccination.

SAT362 - Therapeutic vaccination with CLB-3000 in a mouse model of chronic hepatitis B induces anti-HBs responses associated with functional cure

SAT362 - Therapeutic vaccination with CLB-3000 in a mouse model of chronic hepatitis B induces anti-HBs responses associated with functional cure

Demonstration of durable hepatitis B immune memory in children vaccinated with a DTaP5-IPV-HepB-Hib infant-toddler series 7 to 8 years previously

ABSTRACT Vaccination against hepatitis B (HepB) provides long-term protection against infection. This is despite a reduction in HepB surface antibody (anti-HBs) concentrations over time to levels below the well-accepted correlate of protection of ≥10 mIU/mL. Continued evidence of immune memory and protection despite declined anti-HBs concentrations can be demonstrated by HepB virus surface antigen challenge studies. Long-term immune memory and protection against HepB infection has not been demonstrated previously for the pediatric hexavalent vaccine DTaP5-IPV-HepB-Hib. This phase 3, multicenter, single-group, open-label challenge study (NCT04490499; EudraCT: 2020–000126–26) evaluated immune memory against HepB infection in children who had received DTaP5-IPV-HepB-Hib at 2, 4, and 11–12 months of age, or at 2, 3, 4, and 12 months of age. At age 8–9 years, they were each challenged with 5 μg of monovalent HepB vaccine. Anti-HBs levels were measured on pre-challenge day 1 and post-challenge day 30. At baseline, 45.4% (93 of 205) had anti-HBs levels ≥10 mIU/mL. On post-challenge day 30, 99.5% (201 of 202) had anti-HBs levels ≥10 mIU/mL, regardless of initial vaccination schedule. Post-challenge, geometric mean concentrations increased 71-fold over baseline and 96.0% of children had a ≥4-fold rise in anti-HBs concentrations with similar results across both dosing schedules. The challenge dose was well tolerated. The robust anti-HBs responses after a single 5-μg dose of HepB vaccine confirm the persistence of a HepB immune memory and demonstrate that DTaP5-IPV-HepB-Hib provides long-term protection against HepB.

Immune Response to anti-HBs Antibodies in Health Workers Following Hepatitis B Vaccination

According to Regulation No. 53 of 2015 of the Minister of Health of the Republic of Indonesia, a high risk of HBV infection in health workers is a problem that requires attention, and vaccination knowledge is critical to reducing these risk factors. Furthermore, because some people do not produce a sufficient antibody-forming (anti-HBs) response to HBsAg, testing for evidence of protective immunity against hepatitis B vaccination is required (Hepatitis B Surface Antigen). The purpose of the study was to determine the mapping of the characteristics of anti-HBs antibodies response after hepatitis B vaccination in health workers in terms of age, gender, ethnicity, smoking habits, obesity, vaccination frequency, last time of vaccination. Sixty vaccinated health workers were used to creating the research sample. Anti-HBs levels/titers in serum were measured using the Enzyme-Linked Immunosorbent Assay (ELISA) method, and a questionnaire was used to compile the data for this study. Age, gender, smoking, obesity, and vaccination dose were all used to map the outcomes of the anti-HBs antibody immune response study. Anti-HBs antibody response in health workers was graded as poor in 36 people (60%) and strong in 24 (40%). Regarding ethnic origin, lifestyle, obesity, and vaccination dose (frequency), there was no significant link between post-vaccination anti-HBs antibody response in health workers. In terms of age and gender, there is a strong association between post-vaccination anti-HBs antibody responses in health workers. Low antibody titers should be revaccinated to enhance anti-HBs titers, and health workers who smoke should quit because it reduces the levels of anti-HBs titers produced clinically.

From the Editor’s Desk...

From the Editor’s Desk...

Immune response to hepatitis B vaccine following complete immunization of children attending two regional hospitals in the Southwest region of Cameroon: a cross sectional study

BackgroundHepatitis B virus (HBV) infection despite being a vaccine preventable disease remains a global public health problem. In Cameroon, the hepatitis B vaccine was introduced in the expanded program on immunisation in 2005, but there has been limited evaluation of the HBV surface antibody response post vaccination.ObjectiveWe investigated the immune response to hepatitis B vaccine in infants who received the DPT-Hep B-Hib vaccine, and we assessed HBsAg carriage in non-responders. We also investigated factors associated with non-response or poor response.MethodsUsing a hospital based cross sectional design and a structured questionnaire over a four-month period (January to April 2019), we collected data to determine factors associated with hepatitis B surface antibody (anti-HBs) response from infants aged 6 to 9 months attending infant welfare clinics (IWC) at the Buea and Limbe regional hospitals. We collected venous blood and measured anti-HBs titres using a quantitative Foresight® ELISA. We entered and analysed data using EpiData version 3.1 and SPSS version 25 respectively.ResultsOf the 161 infants enrolled, 159 (98.8%) developed anti-HBs antibodies. Of these 159, 157 (97.5%) and 117 (72.7%) developed ≥ 10.0 mIU/ml (seroprotection) and ≥ 100.0 mIU/ml anti-HBs titres respectively. Being younger (6 months old) was associated with seroprotection (Cramer V = 0.322, p = 0.001). Spearman rho’s relational analysis showed that immunity against HBV reduced as the duration since the last dose increased (r = −0.172; P = 0.029). However, a Firth logistic regression showed no significant association of factors with inadequate immunity. All 12 (7.5%) infants exposed to HBV at birth, received the hepatitis B vaccine at birth, including four who received HBIG, and all were protected. Four infants (2.5%) had anti-HBs titres < 10.0 mIU/mL (non-responders) but had no peculiarity.ConclusionThe seroprotective rate following hepatitis B vaccination of infants is high even in exposed infants. Our study suggests that Cameroon’s HBV vaccine in the Expanded Program on Immunisation (EPI) is effective against HBV, although we could not account for the 2.5% non-response rate. Large scale studies are needed to further explore non-response to the vaccine.

12 Months Persistent Immunogenicity after Hepatitis B Vaccination in Patients with Type 2 Diabetes and Immunogenicity of Revaccination in Non-Responders: An Open-Label Randomized Controlled Trial.

Background: In initial studies, the immunogenicity and safety of hepatitis B vaccines in patients with diabetes has been assessed in China. Methods: In six township health centers in Gansu Province, 232 diabetic patients and 77 healthy people were allocated to receive two 3-dose hepatitis B vaccines (Group D20SC 0-1-6; Group D20CHO 0-1-6; Group ND20SC 0-1-6). Participants were followed up at 12 months after being fully vaccinated. One dose of the vaccine was randomly administered to non-responders. Chi-square test was used to compare the differences in response rate between two groups. Results: The anti-HBs response rates of three groups decreased from 84.1%, 89.1% and 88.3% at one month to 64.6%, 79.8% and 71.4% at twelve months. There was no statistical difference in the immune response rates between Group D20SC 0-1-6 and Group ND20SC 0-1-6; however, that of Group D20CHO 0-1-6 was higher than that of Group D20SC 0-1-6. After revaccination, the geometric mean concentrations were 491.7 mIU/mL and 29.7 mIU/mL after using vaccines containing 60 μg and 20 μg HBsAg. Conclusions: At 12 months, immune response in diabetic patients were not significantly different from that in healthy people. Revaccination with one dose of hepatitis B vaccine containing 60 μg HBsAg for non-responders was more satisfactory.

Therapeutic vaccine BRII-179 restores HBV-specific immune responses in patients with chronic HBV in a phase Ib/IIa study

Background & AimsFunctional cure of chronic HBV infection (CHB) without life-long treatment requires the restoration of defective HBV-specific humoral and cellular immunity. Therapeutic vaccines based on the major structural and non-structural proteins have been tested in patients with CHB but have shown scarce immunogenicity. BRII-179, also known as VBI-2601, is a novel formulation comprised of all 3 HBV surface envelope proteins (Pre-S1, Pre-S2, and S). Safety, antiviral activity, and immunogenicity of BRII-179 admixed with co-adjuvant interferon (IFN)-α were assessed in patients with CHB.MethodThis randomized, open-label, controlled phase Ib/IIa study included 2 dose levels, 20 μg BRII-179 (Part 1, n = 25) and 40 μg BRII-179 (Part 2, n = 24). Patients, virally suppressed under nucleos(t)ide analogue (NA) therapy were randomized 1:2:2 into 3 cohorts in Part 1 and 1:1 into 2 cohorts in Part 2 to receive 4 monthly intramuscular injections of BRII-179 admixed with/without 3 MIU IFN-α. Antibody and cellular responses to HBsAg, as well as evolution of circulating HBsAg were monitored.ResultsBoth 20 μg and 40 μg BRII-179 with/without IFN-α were well tolerated with no severe adverse events. BRII-179 induced anti-HBs responses in >30% patients in all treatment cohorts, however, moderate anti-Pre-S1 or anti-Pre-S2 antibody responses were only observed in patients receiving BRII-179 with IFN-α. BRII-179 also restored S-, Pre-S1-, Pre-S2-specific IFN-γ-producing T-cells in the majority of treated patients. Overall, no notable reduction of HBsAg was observed after BRII-179 treatment.ConclusionIn patients with CHB under NA therapy, BRII-179 with/without IFN-α exhibited a good safety profile and induced HBV-specific B- and T-cell immune responses. These data support further clinical evaluation of BRII-179 in combination with other therapies.Clinical Trial NumberACTRN12619001210167Lay summaryBRII-179 is a therapeutic vaccine designed to improve the immune response in patients with chronic hepatitis B. In this study, BRII-179 alone or with a low dose of interferon-α was safe, well tolerated, and induced enhanced HBV-specific antibody and T-cell responses in patients with chronic hepatitis B. However, BRII-179 treatment alone had minimal effect on patient’s virological status. The potential of BRII-179 to achieve a functional cure in conjunction with other agents is being evaluated in the clinic.

O-18 IMPAIRED ANTI-HBV VACCINE RESPONSE IN NON-CIRRHOTIC CHRONIC HCV PATIENTS IS NOT OVERCOME BY DOUBLE DOSE REGIMEN. FOURTH DOSE MAYBE THE ANSWER!

Hepatitis B virus (HBV) vaccination is regarded as the most effective method for the prevention and control of HBV infection. Studies showed a reduced HBV vaccine response between patients with chronic hepatitis C (HCV), but studies exploring HBV vaccine efficacy in this population have equivocal results. To evaluate HBV vaccine response in patients with HCV submitted to two different (20 µg vs 40 µg in 0, 1 and 6 months) anti-HBV vaccine schemes and administer the 4 th additional dose in non-responders as well as assess the maintenance of seroprotectors titers. This randomized controlled trial included 141 HCV who received double dose (40ug) or standard dose (20ug) and 70 healthy volunteers who received standard dose (20ug) at 0, 1 and 6 months. Anti-HBs titers were measured at 1 month after last dose. Vaccine response was defined by anti-HBs ≥10 U/L. Non-responders received the fourth dose according to the group that were previously randomized. Multivariate regression was modeled as a logistic regression. 128 completed the study. Median age 51 years, 61% female, 52% White, 40% F2-3, and 75% GT1, median 6 log10 HCV RNA. Overall seroconversion rate was 76.7% (n=60) in double dose and 73.5% (n=68) in standard dose, compared to 91.2% in controls (n=68). 23 patients received the fourth dose; 7 seroconverted (30.4%) and seroconversion rate for double and standard doses were 42.9% and 11.1%, respectively ( p =0.18). Controlling for confounders, only older age ( p <0.001) and GT1 ( p =0.005) were associated with a decreased anti-HBs response. In HCV-infected patients without cirrhosis, responses to HBV vaccination are significantly impaired and this reduced response cannot be overcome by the use double dose. Besides that, 4 th dose HBV vaccination can be a strategy efficacious this vulnerable population.

Role of anti-HBs in functional cure of HBeAg+ chronic hepatitis B patients infected with HBV genotype A

HBsAg-specific antibody responses are difficult to detect during chronic hepatitis B infection (CHB) and are often overlooked. The aim of this study was to examine whether anti-HBs may be involved in functional cure (FC) by profiling anti-HBs responses in patients with CHB using a panel of specific assays. Longitudinal serum samples were obtained from 25 patients with CHB who were infected with HBV genotype A and were undergoing nucleos(t)ide analogue (NA) treatment: 14 achieved FC while 11 remained infected (non-FC). Anti-HBs immune complexes (HBsAg-IC), FcγRIIIa dimer binding, epitope specificity and neutralisation efficacy were measured. HBsAg-IC peaks were detected prior to HBsAg loss in 10/14 FC patients. These HBsAg-IC peaks overlapped with either an alanine aminotransferase (ALT) flare (8/10 patients), or a rise in ALT (2/10 patients). HBsAg-IC peaks were detected in 7/11 non-FC patients, but were not associated with an ALT flare. FCγRIIIa binding was detected in 9/14 FC patients, independent from detection of overlapping HBsAg-IC/ALT peaks. FC patients had stable HBsAg epitope occupancy across the study, whereas non-FC patients had a reduction in HBsAg epitope occupancy within the first 12-24 weeks of NA treatment. Convalescent sera from FC patients recognised more HBsAg epitopes and neutralised HBV infection more potently than anti-HBs derived from vaccinees. Neutralisation potency appeared to increase post-HBsAg loss in 4/5 FC patients examined. Using these assays, we confirm that anti-HBs responses are present and fluctuate over time in this cohort of patients with HBeAg+ CHB, who were infected with HBV genotype A and treated with NAs. Key anti-HBs profiles associated with either FC or failure to achieve FC were also identified, suggesting a role for anti-HBs responses in FC. Using a panel of assays to characterise hepatitis B surface antibody (anti-HBs) responses in a group of patients with chronic hepatitis B, we identified anti-HBs profiles associated with either functional cure, or failure to achieve functional cure. Functional cure was associated with immune complex peaks which overlapped with alanine aminotransferase flares. Conversely, in those who did not achieve functional cure, immune complex peaks were present, but were not associated with alanine aminotransferase flares, and a decline in anti-HBs diversity was observed early during treatment.

Clinical Characteristics of Children With Celiac Disease Not Responding to Hepatitis B Vaccination in India.

This study was undertaken to assess the immune response to HBV vaccine in CD children and to explore the possible factors affecting the immune response. The study population consisted of 3 groups-50 newly diagnosed CD children (group 1), 50 previously diagnosed CD children who were on gluten free diet (GFD) >3 months (group 2), and 100 age and gender matched healthy controls (group 3). The patient characteristics were recorded, and the blood samples were analyzed for HBsAg and anti-HBs titers. The nonresponders were given a booster dose of HBV vaccine and reevaluated after 6 weeks. Positive anti-HBs response was found in 46% in newly diagnosed CD children, 60% in CD children on GFD, and 83% in healthy controls (P < 0.001). The immune response to HBV vaccine in CD children was inferior to that in healthy children (53% vs 83%, P < 0.001). The immune response was found to be significantly affected by age at diagnosis, delay in diagnosis, type of presentation, and compliance to GFD. 44 out of 45 (97.77%) nonresponders from CD group seroconverted after a single booster dose. Early diagnosis and good compliance to GFD may improve the immune response to HBV vaccine in CD children. Single additional booster dose is sufficient to attain optimal immune response.

European Recommendations for the Management of Healthcare Workers Occupationally Exposed to Hepatitis

Exposure prevention is the primary strategy to reduce the risk of occupational bloodborne pathogen infections in healthcare workers (HCW). HCWs should be made aware of the medicolegal and clinical relevance of reporting an exposure, and have ready access to expert consultants to receive appropriate counselling, treatment and follow-up. Vaccination against hepatitis B virus (HBV), and demonstration of immunisation before employment are strongly recommended. HCWs with postvaccinal anti-HBs levels, 1-2 months after vaccine completion, -or=10 mIU/mL are considered as responders. Responders are protected against HBV infection: booster doses of vaccine or periodic antibody concentration testing are not recommended. Alternative strategies to overcome non-response should be adopted. Isolated anti-HBc positive HCWs should be tested for anti-HBcIgM and HBV-DNA: if negative, anti-HBs response to vaccination can distinguish between infection (anti-HBs -or=50 mIU/ml 30 days after 1st vaccination: anamnestic response) and false positive results(anti-HBs -or=10 mUI/ml 30 days after 3rd vaccination: primary response); true positive subjects have resistance to re-infection. and do not need vaccination The management of an occupational exposure to HBV differs according to the susceptibility of the exposed HCW and the serostatus of the source. When indicated, post-exposure prophylaxis with HBV vaccine, hepatitis B immunoglobulin or both must be started as soon as possible (within 1-7 days). In the absence of prophylaxis against hepatitis C virus (HCV) infection, follow-up management of HCV exposures depends on whether antiviral treatment during the acute phase is chosen. Test the HCW for HCV-Ab at baseline and after 6 months; up to 12 for HIV-HCV co-infected sources. If treatment is recommended, perform ALT (amino alanine transferase) activity at baseline and monthly for 4 months after exposure, and qualitative HCV-RNA when an increase is detected. Introduction Bloodborne pathogens such as hepatitis B (HBV) and C virus (HCV) represent an important hazard for healthcare workers (HCWs) [1]. In the general population, HCV prevalence varies geographically from about 0.5 percent in northern countries to 2 percent in Mediterranean countries, with some 5 million chronic carriers estimated in Europe; while HBV prevalence ranges from 0.3 percent to 3 percent. The World Health Organization (WHO) estimates that each year in Europe 304 000 HCWs are exposed to at least one percutaneous injury with a sharp object contaminated with HBV, 149 000 are exposed to HCV and 22 000 to HIV. The probability of acquiring a bloodborne infection following an occupational exposure has been estimated to be on average. Bloodborne pathogens such as hepatitis B (HBV) and C virus (HCV) represent an important hazard for healthcare workers (HCWs) [1]. In the general population, HCV prevalence varies geographically from about 0.5 percent in northern countries to 2 percent in Mediterranean countries, with some 5 million chronic carriers estimated in Europe; while HBV prevalence ranges from 0.3 percent to 3 percent. The World Health Organization (WHO) estimates that each year in Europe 304 000 HCWs are exposed to at least one percutaneous injury with a sharp object contaminated with HBV, 149 000 are exposed to HCV and 22 000 to HIV.We present here recommendations for the general management of occupational risk of bloodborne infections, HBV vaccination and management of HBV and HCV exposures. A description of the project and recommendations for HIV post-exposure management, including antiretroviral prophylaxis, has been previously published [2], and so issues related to occupational risk and prevention of HIV infection following an occupational exposure will not be discussed further.

STUDY OF THE IMMUNOGENICITY OF RECOMBINANT HEPATITIS B VACCINE: COMPARISON OF TWO NATIONAL IMMUNIZATION PROGRAMS IN EGYPT

Hepatitis B virus, approximately 2 billion persons, one-third of the world's population, have serologic evidence of past or ongoing infection with the virus. Average 1 million die of hepatitis and its consequences each year. HBV is considered moderately endemic in Egypt with 4% of the population having evidence of chronic HBV infection. Nearly 2 - 3 million Egyptians are chronic carriers of HBV. Vaccination against hepatitis B is the most effective strategy to control HBV infection. Human beings are the sole major reservoir of HBV and hence a complete control strategy by HBV vaccination could lead to virus eradication. HBV vaccine is the first vaccine against a major human cancer. The highest anti-HBs titers are attained 1–3 months following administration of the primary course of hepatitis B vaccine, and are considered a reliable marker of immediate and long-term protection against infection. Anti-HBs response is significantly enhanced after the third injection, with an overall 97–100% anti-HBs ≥10 IU/L. In intermediate and highly endemic countries, universal vaccination without screening of pregnant women is clearly cost-effective. Vertically transmitted HBV infection is becoming an important risk factor for acquisition of HBV among children born after the era of mass vaccination in Egypt. A rate of maternofetal transmission of 51.8% was reported among HBsAg-positive women in Egypt and routine HBV antenatal screening is not practiced. So, stimulated us to perform this work in order to assess the effect of adding the birth dose of HBV vaccine to Egypt’s national immunization program.

Single Hepatitis B Booster Dose in High-risk Children with Suboptimal Surface Antigen Antibody Responses After 3-dose Primary Vaccine Series

This was a descriptive study of 30 children born to HBsAG positive mothers between June 2009 and December 2013. All children had anti-HBs response ≤100 IU/L after 3 doses of hepatitis B vaccine primary series. A single booster dose led to hepatitis B surface antibody titers ≥100 IU/L in (85%) of children.