The prevalence of hepatitis B core antibody in vaccinated Chinese children: A hospital-based study

Seropositivity of antibody to hepatitis B core antigen among hepatitis B surface antigen-negative vaccinated individuals aged 5-12 years in North West Ethiopia

Background

Infection with the hepatitis B virus (HBV) is still a major global public health concern, especially in Ethiopia. Evidence suggests that some children in Ethiopia who have received hepatitis B vaccinations are still contracting HBV.

Objective

The main aim of this study was to detect antibodies to hepatitis B core antigen (anti-HBc) among vaccinated hepatitis B surface antigen (HBsAg)-negative individuals in North-West Ethiopia.

Methods and materials

A community-based cross-sectional study was conducted among 158 children aged 5-12 years from April 2021 to November 2021. A simple random sampling technique was used to recruit study participants. After 3-5 ml of venous blood was drawn from each study participant, a serum sample was utilized to determine hepatitis B surface antigen (HBsAg) and anti-hepatitis B core antibodies (anti-HBc) by enzyme-linked immunosorbent assay (ELISA). Logistic regression with a 95 % CI was used to show the statistical association.

Results

The total seropositivity of anti-HBc among vaccinated HBsAg-negative participants was 8/158 (5.1 %) (95 % CI: 2.0-9.0). Multivariable logistic regression revealed that children who had a previous history of blood transfusion were six times (AOR: 6.135, 95 % CI: 4.063, 10.752) (P < 0.006) more likely to develop anti-HBc. Moreover, children who had a previous history of surgery were five times (AOR: 5.116, 95 % CI: 3.123, 8.718) (P < 0.002) more likely to become anti-HBc seropositive.

Conclusion

There was a significant seroprevalence of anti-HBc in our study area, suggesting possible exposure to the virus despite immunization.

Evaluating the hepatitis B vaccination impact in the Republic of Moldova: A nationwide representative serosurvey of children born in 2013

Objectives

The WHO European Region set targets for the control of hepatitis B through immunization, including prevalence of hepatitis B surface antigen (HBsAg) at ≤0.5% in vaccinated cohorts. The Republic of Moldova implemented universal hepatitis B vaccination since 1995. We conducted a nationwide representative serosurvey to estimate HBsAg seroprevalence in children born in 2013 to validate hepatitis B control targets.

Methods

We used probability-based sampling and a two-stage cluster design. All children born in 2013 and registered in primary healthcare facilities were eligible for participation. We tested blood samples of all participants for hepatitis B core antibody (anti-HBc), using Enzyme-Linked Immunosorbent Assay (ELISA). Anti-HBc-positive samples were tested for HBsAg and HBsAg-positive samples confirmed, using ELISA. We obtained information on hepatitis B vaccination from vaccination cards.

Results

Of 3352 sampled children, 3064 (91%) participated. Most participating children were 7 years old (n = 3030, 99%), 1426 (48%) were girls. The weighted, national seroprevalence estimate was 3.1% (95% confidence interval = 2.1-4.5) for anti-HBc and 0.21% (95% confidence interval = 0.08-0.53) for HBsAg.

Conclusion

The study demonstrated the impact of hepatitis B vaccination and allowed the Republic of Moldova to validate regional hepatitis B control targets. Other countries with high vaccination coverage could use hepatitis B serosurveys and apply for validation. Sustained efforts in the Republic of Moldova will be crucial on the path to hepatitis B elimination.

Complementary Presence of HBV Humoral and T-cell Response Provides Protective Immunity after Neonatal Immunization

BACKGROUND AND AIMS

Hepatitis B vaccination is the most cost effective way to prevent hepatitis B virus (HBV) infection. Hepatitis B vaccine (HepB) efficacy is usually assessed by anti-hepatitis B surface antigen (HBsAg) level, but there are few reports of humoral and cellular immune responses to HepB in children after neonatal vaccination.

METHODS

A group of 100 children with a history of primary hepatitis B immunization were included in this study to evaluate the efficacy of HepB. Blood samples were obtained from 80 children before, and 41 children after, a single HepB booster dose. Children with low anti-HBsAg (HBs) titers of <100 mIU/mL received a booster dose after giving their informed consent. Anti-HBsAg, T-cell response and percentage of B-cell subsets were assayed before and after the booster.

RESULTS

Of the 80 children, 81.36% had positive T cell and anti-HBsAg responses at baseline. After the booster dose, the anti-HBsAg titer (p<0.0001), positive HBsAg-specific T-cell response (p=0.0036), and spot-forming cells (p=0.0003) increased significantly. Compared with pre-existing anti-HBsAg titer <10 mIU/mL, the anti-HBsAg (p=0.0005) and HBsAg-specific T-cell responses (p<0.0001) increased significantly in preexisting anti-HBsAg titer between 10 and 100 mIU/mL group. Change of the HBV-specific humoral response was the reverse of the T-cell response with age. Peripheral blood lymphocytes, B cells, and subset frequency decreased.

CONCLUSIONS

HBV immunization protection persisted at least 13 years after primary immunization because of the complementary presence of HBV-specific humoral antibodies and a T-cell immune response. One dose of a HepB booster induced protective anti-HBsAg and promoted an HBsAg-specific T-cell response. In HBV endemic regions, a HepB booster is recommended to children without anti-HBsAg because of effectiveness in HBV prevention.

Booster immunization improves the generation of T follicular helper (Tfh) cells specific to hepatitis B surface antigen (HBsAg) after prenatal HBsAg exposure

Breakthrough infections of hepatitis B virus (HBV) after neonatal vaccination occurred in some adolescents and young adults who were born to mothers with hepatitis B surface antigen (HBsAg). We aimed to determine the impacts of prenatal HBsAg exposure on the generation of T follicular helper (Tfh) cells and antibodies (anti-HBs) specific to HBsAg. To mimic human prenatal HBsAg exposure, we mated female Alb1-HBV (HBV-M) mice with male C57BL/6J mice. Of their first filial generation (F1), HBV-M/F1+ expressed HBsAg in liver tissues and blood, and HBV-M/F1- mice exposed HBsAg in amniotic fluid. At their four weeks old, each HBV-M/F1 mouse was immunized with hepatitis B vaccine containing 5 μg HBsAg subcutaneously. Both HBV-M/F1- and HBV-M/F1+ mice had reduced generation of HBsAg-specific CD4+CXCR5+PD1+ Tfh cells and CD138+IgD- plasma cells in comparison with C57BL/6J mice. Results of coculturing the Tfh cells with B cells that were isolated from different strains of mice indicated that CD4+ T cell activation in response to HBsAg was critical for anti-HBs generation after prenatal HBsAg exposure. When interleukin (IL) 21 was supplemented, the generation of HBsAg-specific Tfh and plasma cells in HBV-M/F1- mice was improved, while supplementation showed little effect in HBV-M/F1+ mice. In HBV-M/F1- mice, HBV vaccine booster improved the generation of Tfh cells and plasma cells, and enhanced anti-HBs production. CONCLUSION: Impaired generation of HBsAg-specific Tfh cells and plasma cells after prenatal HBsAg exposure can be improved by HBV vaccine booster, most likely increasing IL-21 production.

Changing trends in seroprevalence rates of transfusion-transmitted diseases among blood donors in Jordan

Background

Hepatitis B and C infections and transmission are a serious challenge to all healthcare systems. We studied seroprevalence rates of Transfusion Transmitted Diseases (TTD) among blood bank donors in Jordan from 2014 to 2019 as a follow-up study of our previously published work. In addition, we wanted to explore the efficacy of the mandatory vaccination of infants against hepatitis B virus (HBV) which was implemented by the Ministry of Health since 1995 for the eradication of HBV infection in Jordan.

Methods

We reviewed blood bank donors’ records at King Hussein Cancer Center (KHCC) from January 1st, 2014, until December 31st, 2019. Results of seropositivity prevalence rates for HBsAg, anti-HBcore, and anti-HCV, using Enzyme-Linked ImmunoSorbent Assay (ELISA) were compared to seropositivity rates from our previously published data. In addition, our results were compared to data obtained from other blood banks in Jordan, as well as compared to published information from blood banks in neighboring countries.

Results

The prevalence rates (%) of seropositive blood donors for viral hepatitis for the years 2014, 2015, 2016, 2017, 2018, and 2019, were as follows: HBsAg rates were 0.3386, 0.2108, 0.1801, 0.1898, 0.2068, and 0.2741; anti-HBcore rates were 4.1112, 3.2271, 2.9748, 2.8405, 2.6879 and 3.0986; and anti-HCV rates were 0.1129, 0.0486, 0.0548, 0.0654, 0.0782, and 0.0839, respectively. There was a significant increase in the prevalence of HBsAg, Anti-HBcore and Anti-HCV antibodies in 2019 (one sample z-score test, p < 0.00001).

Conclusions

Prevalence rates of hepatitis B and C infections among Jordanian blood bank donors showed a steady decline between 2009 and 2017, and these rates were much lower in Jordan than in neighboring countries. However, an increase in the prevalence rates of hepatitis B and C infections among blood bank donors was documented in 2019. While the reasons for this increase are not clear yet, these findings highlight the importance of renewed efforts to increase public health awareness of HBV and implement effective measures to prevent the transmission and infection with HBV, including national vaccination programs.

Changing trends in seroprevalence rates of transfusion-transmitted diseases among blood donors in Jordan

BACKGROUND

Hepatitis B and C infections and transmission are a serious challenge to all healthcare systems. We studied seroprevalence rates of Transfusion Transmitted Diseases (TTD) among blood bank donors in Jordan from 2014 to 2019 as a follow-up study of our previously published work. In addition, we wanted to explore the efficacy of the mandatory vaccination of infants against hepatitis B virus (HBV) which was implemented by the Ministry of Health since 1995 for the eradication of HBV infection in Jordan.

METHODS

We reviewed blood bank donors' records at King Hussein Cancer Center (KHCC) from January 1st, 2014, until December 31st, 2019. Results of seropositivity prevalence rates for HBsAg, anti-HBcore, and anti-HCV, using Enzyme-Linked ImmunoSorbent Assay (ELISA) were compared to seropositivity rates from our previously published data. In addition, our results were compared to data obtained from other blood banks in Jordan, as well as compared to published information from blood banks in neighboring countries.

RESULTS

The prevalence rates (%) of seropositive blood donors for viral hepatitis for the years 2014, 2015, 2016, 2017, 2018, and 2019, were as follows: HBsAg rates were 0.3386, 0.2108, 0.1801, 0.1898, 0.2068, and 0.2741; anti-HBcore rates were 4.1112, 3.2271, 2.9748, 2.8405, 2.6879 and 3.0986; and anti-HCV rates were 0.1129, 0.0486, 0.0548, 0.0654, 0.0782, and 0.0839, respectively. There was a significant increase in the prevalence of HBsAg, Anti-HBcore and Anti-HCV antibodies in 2019 (one sample z-score test, p < 0.00001).

CONCLUSIONS

Prevalence rates of hepatitis B and C infections among Jordanian blood bank donors showed a steady decline between 2009 and 2017, and these rates were much lower in Jordan than in neighboring countries. However, an increase in the prevalence rates of hepatitis B and C infections among blood bank donors was documented in 2019. While the reasons for this increase are not clear yet, these findings highlight the importance of renewed efforts to increase public health awareness of HBV and implement effective measures to prevent the transmission and infection with HBV, including national vaccination programs.

Neonatal hepatitis B vaccination protects mature adults from occult virus infection

BACKGROUND

Among elder children/young adults who received hepatitis B virus (HBV) vaccination during infancy, the serological status of HBsAg-negative and anti-HBc-positive [HBsAg(-)/anti-HBc(+)] was frequently reported, indicating potential occult HBV infection (OBI). It is required to define the long-term protection of neonatal vaccination against OBI in their mature adulthood.

METHODS

Building upon the 1983-1990 established Qidong Hepatitis B Intervention Study, we sampled 10% of the 28-35-year-old participants, who remained in the cohort by 2012. Each participant was tested for serological markers of HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc. HBV-DNA and relaxed circular DNA (rcDNA) were determined in some HBsAg(-)/anti-HBc(+) individuals.

RESULTS

Totally, 3615 individuals from the neonatal vaccination group and 3100 individuals from the control group donated blood samples, respectively. In the vaccination group, the prevalence of HBsAg was 1.58% (57/3615), HBsAg(-)/anti-HBc(+) was 4.70% (170/3615), significantly lower than in the control group, which was 7.45% (231/3100) and 19.48% (640/3100) respectively (all p < 0.001). With aging, HBsAg(-)/anti-HBc(+) prevalence increased in the sampled participants from the control group (pfor trend < 0.001), but uncertain from the vaccination group. Of HBsAg(-)/anti-HBc(+), HBV-DNA was detected in 13.08% (17/130) from the vaccination group, and in 4.18% (12/287) from the control group. HBV rcDNA was detected in most sera that were tested positive for HBV-DNA.

CONCLUSIONS

OBI occurred in some vaccinated adults. However, neonatal HBV vaccination kept the effective protection against OBI in mature adults.

Long-term protection at 20-31 years after primary vaccination with plasma-derived hepatitis B vaccine in a Chinese rural community

Background: To assess the long-term protection conferred by plasma-derived hepatitis B vaccine at 20-31y after primary immunization during infancy in Chinese rural community.Method: Participants born between 1986 and 1996, who received a full course of primary vaccination with plasma-derived hepatitis B vaccine and had no experience with booster vaccination were enrolled. An epidemiological investigation was performed, and blood samples were collected to detect hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core antibody (anti-HBc). The positive rate of HBsAg, anti-HBs, and anti-HBc were calculated to evaluate the long-term protection of the plasma-derived hepatitis B vaccine.Results: A total of 949 participants were enrolled in the final analysis. Six subjects were detected to be HBsAg-positive, resulting in a HBsAg carrier rate of 0.63% (6/949). A total of 468 (52.41%) participants maintained a level of anti-HBs antibody ≥10 mIU/mL, with a GMC of 112.20 mIU/mL (95%CI: 97.72 ~ 128.82 mIU/mL). A significant downtrend was observed in the anti-HBs positive rate (P < .001). The average anti-HBc positive rate was 5.90% (56/949), increased with prolongation of immunization (P < .001).Conclusions: The plasma-derived hepatitis B vaccine maintained satisfactory protection at 20-31 y after primary immunization. These results indicate that a booster dose is not necessary. Further studies on the immune memory induced by the plasma-derived hepatitis B vaccine are needed.