Ethnicity, substance use, and response to booster hepatitis B vaccination in anti-HBs-seronegative adolescents who had received primary infantile vaccination

Association of HLA-DPA1, HLA-DPB1, and HLA-DQB1 Alleles With the Long-Term and Booster Immune Responses of Young Adults Vaccinated Against the Hepatitis B Virus as Neonates

The neonatal hepatitis B vaccination (HBVac) was implemented 35 years ago in Taiwan, but many vaccinees exhibit inadequate long-term vaccine-induced seroprotective hepatitis B surface antibody (anti-HBs) levels. We investigated the association of the human leukocyte antigen (HLA) alleles (DPA1, DPB1, DQA1, and DQB1) with the long-term immunological response to the neonatal HBVac and adolescent booster HBVac in a Taiwanese cohort. We divided 281 Han students (median age 22, age range 17–29 years) into the following groups: (1) Group A (n = 61): anti-HBs titer ≥ 10 mIU/mL at the beginning of the study; (2) Group B (n = 75): anti-HBs level > 1000 mIU/mL after the first booster; (3) Group C (n = 37): anti-HBs level < 10 mIU/mL after the first booster; and (4) Group D (n = 5): anti-HBs level < 10 mIU/mL after three boosters. DQA1, DQB1, DPA1, and DPB1 typing of the participants was performed using sequence-specific oligonucleotides. Associations of HLA alleles and haplotypes with effects on neonatal HBVac and booster HBVac were examined through logistic regression analysis and Fisher’s exact test. A false discovery rate-based measure of significance, the q-value, was used for multiple comparisons, and an association was considered significant if the corresponding q-value was < 0.1. DPA1 alleles were associated with the long-term immunological response to the neonatal HBVac. The estimated odds ratio (OR) of the lack of HBV protective immunity when carrying an additional DPA1*01 and DPA1*02 was 0.36 [95% confidence interval (CI) = 0.17–0.76, p = 0.0076] and 2.39 (95% CI = 1.17–4.87, p = 0.016), respectively. DPB1 and DQB1 alleles were associated with a response to the adolescent booster vaccination. The estimated ORs of being nonresponsive to the first booster when carrying an additional DPB1*05 and DQB1*02 were 2.11 (95% CI = 1.13–3.93, p = 0.019) and 3.73 (95% CI = 1.43–9.71, p = 0.0070), respectively. All DPB1*03 carriers responded to the first booster (p of Fisher’s exact test = 0.0045). In our study, we discovered that HLA-DPA1 was primarily associated with the long-term response of primary infantile HBVac, and HLA-DPB1 and HLA-DQB1 exhibited associations with the HBV booster vaccination.

How does the immunogenicity of hepatitis B vaccine change over the years in childhood?

Hepatitis B is the leading cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma worldwide. The incidence of HBV infection has significantly decreased with hepatitis B vaccination. Hepatitis B vaccine is administered to children at 0, 1 and 6 months of age according to the national schedule. There is a high rate of protective antibody (anti-HBs) development after hepatitis B vaccination. We conducted the study to investigate how the hepatitis B surface antibody (anti-HBs) positivity rates and the titers change over time in childhood following vaccination. Patients who presented at the general pediatric outpatient clinic of Yenimahalle Education and Training Hospital and the HBsAg and anti-HBs titers were tested for any reason between July 2011 and May 2018 were retrospectively evaluated. The cutoff level for protection by the anti-HBs titer was accepted as ≥10 mIU/mL with lower levels indicating no protection. Anti-HBs positivity was compared by age group. Anti-HBs levels were studied in 4326 children. The mean age of the included in the study was 127 ± 62 months. A protective anti-HBs level (≥10 mIU/mL) was present in 2292 children (69.2%). The highest anti-HBs antibody positivity rate was in the under 3 years' age group. The positivity rate significantly decreased after age 7 years. The HBsAg level was determined in all children in the study and five had a positive result. In conclusion, our study found that the anti-HBs positivity rate and the anti-HBs level decreased with age. However, the anti-HBs antibody result remained positive in more than half of the children.

Ethnicity and response to primary three-dose hepatitis B vaccination in employees in the Netherlands, 1983 through 2017

BACKGROUND AND AIMS

Hepatitis B virus (HBV) vaccination is recommended to all employees who have an occupational risk in the Netherlands. This study assessed the determinants of the immune response to primary standard three-dose HBV vaccination (0, 1, 6 months), with the main focus on ethnicity.

METHODS

Out of 76 239 individuals who received HBV vaccination between April 1983 and December 2017, 11 567 persons with a known country of birth and complete vaccination schedule were included in this study. Weighted multiple logistic regression with Firth's bias adjustment was used to assess the determinants of nonresponse (anti-HBs < 10 mIU/mL) and low response (anti-HBs 10-99 mIU/mL).

RESULTS

Baseline characteristics of the study population (n = 11 567) were as follows: mean age 27.5 years (95% confidence interval [CI], 27.23-27.72), 99.4% born in the Netherlands and 93.5% of Western European origin. Of all identified subjects, 180 (1.6%) were HBV vaccine nonresponders and 549 (4.8%) were low responders. When compared with individuals aged <40 years, the rate of nonresponse (4.3% vs 0.8%; P < .001) and low response (11.9% vs 2.9%; P < .001) was higher in those aged 40 years or older. The height of anti-HBs levels were lower in those subjects aged >40 years in comparison with those younger than 40 years, P < .001. All nonresponders were born in the Netherlands. Although no significant association was found between nonresponse and individuals of Western European origin (adjusted odds ratio [aOR] = 1.20; 95% CI, 0.66-2.44; P = .163), low response to HBV vaccination was significantly associated with Western European origin (aOR = 2.21; 95% CI, 1.41-3.86; P = .001). Significant determinants for nonresponse were older age at vaccination (aOR = 1.06; 95% CI, 1.06-1.07; P < .001) and male gender (aOR = 2.51; 95% CI, 1.97-3.22; P < .001).

CONCLUSIONS

The nonresponse rate was low in our study population. Our findings suggest that the vaccines being used for the primary vaccination are probably less immunogenic for older individuals, males, and persons of Western European origin.

Early and long term anamnestic response to HBV booster dose among fully vaccinated Egyptian children during infancy

OBJECTIVE

To evaluate early and long term anamnestic response to a booster dose of HBV vaccine among non-seroprotected children.

SUBJECTS AND METHOD

A national community based project was carried out on 3600 children aged 9 months to 16 years, fully vaccinated during infancy. They were recruited from 6 governorates representing Egypt. It revealed that 1535 children (42.8%) had non sero-protective anti-HBs (<10 IU/L) and were HBsAg or anti-HBc negative. A challenging dose of 10 μg of mono-valent Euvax HBV vaccine was given to 1121/1535 children. Quantitative assessment of anti-HBs was performed to detect early (2-4 weeks) and long term (one year) anamnestic responses.

RESULTS

Early anamnestic response developed among 967/1070 children (90.3%).Children having detectable anti-HBs (1-9 IU/L) significantly developed early anamnestic response (90%) compared to 85% with undetectable anti-HBs (<1 IU/L), P < 0.001. Multiple logistic analysis revealed that undetectable anti-HBs, living in rural residence and children aged 15-16 years were the most significant predicting risk factors for the absence of early anamnestic response (<10 IU/L), with AOR 2.7, 2.7 & 4.7 respectively. After one year, long term anamnestic response was absent among 15% of children who previously showed early response. Poor early anamnestic response and undetectable pre-booster anti-HBs were the significant predicting risk factors for absent long term anamnestic response, with AOR 18.7 & 2.7 respectively.

CONCLUSION

Immunological memory for HBV vaccine outlasts the presence of anti- HBs and HBV vaccination program provides effective long term protection even in children showing waning or undetectable concentrations of anti-HBs. This signifies no need for a booster dose especially to healthy children.

Hepatitis B Seroprotection and the Response to a Challenging Dose among Vaccinated Children in Red Sea Governorate

AIM:

To assess the long-term effectiveness of hepatitis B virus vaccine and the need for a booster dose among children who received three doses of vaccine during infancy in Red Sea Governorate.

METHODS:

A cross-sectional study was performed. Interviews with children (9 months to 16 years) and parents were done. Blood samples to assess Hepatitis B markers were tested. Children showing no seroprotection received a booster dose to assess their anamnestic response after four weeks and one year later.

RESULTS:

None of the participants had evidence of chronic Hepatitis B. The seroprotection rate was 23.3% and it significantly decreased with age. Multivariate logistic analysis revealed that older age was the significant predicting variable for having no seroprotective level, while baseline anti-HBs level < 3.3 IU/L was the predicting variable for not developing early anamnestic response or loss of late anamnestic response.

CONCLUSION:

Long-term immunity persists among children who received complete series of hepatitis B vaccination during infancy even in absence or reduction of anti-HBs over time. Therefore, a booster dose is not necessary to maintain immunity till the age of sixteen.

Age-specific prevalence of hepatitis B virus infection in young pregnant women, Hong Kong Special Administrative Region of China

Objective

To investigate the age-specific prevalence of hepatitis B virus (HBV) infection in young pregnant women in Hong Kong Special Administrative Region (SAR), China, and to determine whether an increase in prevalence occurs during adolescence.

Methods

HBV prevalence was quantified using data from routine antenatal screening for hepatitis B surface antigen (HBsAg) in 10 808 women aged 25 years or younger born in Hong Kong SAR and managed at a single hospital between 1998 and 2011. The effect on prevalence of maternal age, parity and birth before or after HBV vaccine availability in 1984 was assessed, using Spearman’s correlation and multiple logistic regression analysis.

Findings

Overall, 7.5% of women were HBsAg-positive. The prevalence ranged from 2.3% to 8.4% in those aged ≤ 16 and 23 years, respectively. Women born in or after 1984 and those younger than 18 years of age were less likely to be HBsAg-positive (odds ratio, OR: 0.679; 95% confidence interval, CI: 0.578–0.797) and (OR: 0.311; 95% CI: 0.160–0.604), respectively. For women born before 1984, there was no association between HBsAg carriage and being younger than 18 years of age (OR: 0.60; 95% CI: 0.262–1.370) Logistic regression analysis showed that the prevalence of HBsAg carriage was influenced more by the woman being 18 years old or older (adjusted OR, aOR: 2.80; 95% CI: 1.46–5.47) than being born before 1984 (aOR: 1.42; 95% CI: 1.21–1.67).

Conclusion

Immunity to HBV in young pregnant women who had been vaccinated as neonates decreased in late adolescence.

Seroepidemiology of hepatitis B virus infection among adults in Singapore: a 12-year review

We undertook a national hepatitis B seroprevalence study to assess the seroprevalence of hepatitis B virus (HBV) markers in the adult population in Singapore in 2010 and make comparisons with the seroprevalence in 1998 and 2004. The study involved residual sera from national health surveys conducted every six years since 1998. The tests for HBV markers were carried out using commercial chemiluminescent microparticle immunoassay. In 2010, the prevalence of hepatitis B surface antigen (HBsAg) among 3293 Singapore residents aged 18-79 years was 3.6% (95% confidence interval [CI] 2.9-4.2%). Hepatitis B e antigen (HBeAg) was detected in 4.2% of those who were HBsAg positive. About 22.5% (95% CI 21.1-23.9%) were positive for antibody to hepatitis B core antigen (anti-HBc). The overall population immunity to HBV, as determined by antibody to hepatitis B surface antigen (anti-HBs)≥ 10 mIU/mL, was 43.9% (95% CI 42.2-45.6%). Among young adults below 30 years of age, HBsAg prevalence (1.1%) was half that in 1998 and 2004, and in those positive for HBsAg, none was positive for HBeAg in 2010, compared to 20.8% in 1998 and 15.8% in 2004. In this age group, anti-HBc prevalence also decreased significantly from 22.1% in 2004 to 4.4% in 2010, while anti-HBs (≥ 10 mIU/mL) prevalence increased significantly from 27.9% in 1998 to 43.3% in 2010 (p<0.001). The national childhood HBV immunisation and catch-up programmes implemented in 1987 and 2001-2004, respectively, had a significant impact in reducing HBV infection and in raising the immunity of the adult population 18-29 years of age.

The relationship between erythropoietin resistance and antibody response to hepatitis B vaccine in hemodialysis patients

Background

Seroconversion following Hepatitis B virus (HBV) vaccine in hemodialysis (HD) patients has been shown to be suboptimal. Nutritional and immunological factors were shown to influence the seroconversion related to HBV vaccination in HD patients. Resistance to erythropoiesis stimulating agents (ESA) for correction of anemia has also been shown to be associated with nutrition and inflammation in these patients.

Objectives

The aim of the current study was to analyze the relationship between anti-HBs response and erythropoietin (EPO) resistance in HD patients.

Patients and Methods

Demographics, clinical characteristics, laboratory parameters and the data about vaccination status were obtained from dialysis charts and vaccination registries retrospectively. To calculate the EPO resistance ESA hypo responsiveness index (EHRI) was used. The EHRI was calculated through deviding the weekly dose of EPO by per kilogram of body weight divided by the hemoglobin level. Patients were divided into non-seroconversion (anti-HBs titers were < 10 IU/L) and seroconversion groups (anti-HBs titers were ≥ 10 IU/L) after completion of the four-dose vaccination schedule.

Results

In total 97 patients were enrolled. For the entire group, stepwise linear regression analysis revealed that square root transformed anti-HBs levels were independently associated with age (P = 0.016), blood urea nitrogen (P = 0.019), high sensitive C-Reactive Protein (P = 0.009), and square root transformed EHRI (P = 0.019). Logistic regression analysis have also demonstrated that blood urea nitrogen (P = 0.002), creatinine (P = 0.046), albumin (P = 0.01) and square root transformed EHRI (P = 0.011) were independently related to seroconversion.

Conclusions

EPO resistance was negatively associated with anti-HBs levels and seroconversion. More studies are needed to highlight the underlying mechanisms regarding EPO resistance and response to HBV vaccination in HD patients.

Vaccine-Induced Anti-HBs Level in 5-6 Year-Old Malnourished Children

BACKGROUND

Malnutrition is the most common cause of immune deficiency. It results in reduced secretion of T-cells and B-cell-stimulating factors leading to declining of special immunoglobulins. On the other hand, hepatitis B, as a major world health problem, can be prevented effectively by vaccination. Three doses of hepatitis B virus (HBV) vaccine induce protective levels of anti-hepatitis B surface (anti-HBs) in 95% of healthy children. This level decreases gradually over time.

OBJECTIVES

The goal of this study was to assess anti-HBs in malnourished children, who confronted to some degrees of immune deficiency.

PATIENTS AND METHODS

This is a cross-sectional study conducted during May to August 2010 in therapeutic clinics of Yazd, Iran. Samples were selected simply and consecutively among 5-6 year-old children with a history of three doses of HBV vaccine in infancy. On the basis of World Health Organization's definition on malnutrition, which considers anthropometric measurements, malnourished children entered the study. Totally 83 cases (37 boys and 46 girls) were gathered and classified into three groups of mild, moderate, and severe malnutrition. One milliliter of venous blood was taken and anti-HBs were tested by enzyme linked immunosorbant assay (ELISA).

RESULTS

Overall, seroprotection rate and geometric mean titer (GMT) of anti-HBs were 60.2% and 15.47 ± 10.92 mIU/mL, respectively. Seroprotection rate was 71.4%, 55.2%, and 72.7% in mild, moderate, and severe malnourished children, respectively. GMT was 30.78 mIU/mL, 12.15 mIU/mL, and 22.95 mIU/mL in these groups, respectively. None of these two indices were significant in these groups (P = 0.471, P = 0.364). Seroprotection rate and GMT were 54.1% and 13.26 ± 11.59 mIU/mL in boys, and 65.2% and 17.5 ± 10.59 mIU/mL in girls, respectively, showing no significant relationship with gender (P = 0.302, P = 0.602). Lowest seroprotection rate was in stunted cases (47.1%) and highest in wasted children (77.8%). This difference also was not significant (P = 0.43).

CONCLUSIONS

The seroprotection rate and GMT of anti-HBs observed in this study do not show a high level of immunity. These two indices were not related to severity of malnutrition. We conclude that severity of malnutrition does not affect vaccine-induced antibody level and seroprotection rate; however small sample size in each group of study hinders decisive conclusion. Moreover, GMT and seroprotection rate showed no relationship with type of abnormal anthropometric index, including weight for height, weight for age, and height for age.

Chronic hepatitis B infection in adolescents who received primary infantile vaccination

Hepatitis B virus (HBV) infection is a global health issue. Universal infantile hepatitis B (HB) vaccination is very efficacious. However, HBV infections among those immunized subjects have been reported. The long-term efficacy of postnatal passive-active HB vaccination in high-risk subjects is not well explored. A total of 8,733 senior high school students who were born after July 1987 were assayed for hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs). The overall HBsAg and anti-HBs-positive rates were 1.9% and 48.3%, respectively. The HBsAg-positive rate was 15% in HB immunoglobulin (HBIG) recipients (adjusted odds ratio [OR]: 15.63; 95% confidence interval [CI]: 10.99-22.22). Among students who did not receive HBIG, there was a significantly negative association between HB vaccination dosage and HBsAg-positive rate (P for trend = 0.011). Adjusted ORs for those who received 4, 3, and 1 to 2 doses were 1.00, 1.52 (95% CI: 0.91-2.53), and 2.85 (95% CI: 1.39-5.81), respectively. Among HBIG recipients, the HBsAg-positive rate was significantly higher in subjects with maternal hepatitis B e antigen (HBeAg) positivity and who received HBIG off-schedule. A booster dose of HB vaccination was administered to 1974 HBsAg- and anti-HBs-negative subjects. Prebooster and a postbooster blood samples were drawn for anti-HBs quantification. The proportions of postbooster anti-HBs titer <10 mIU/mL was 27.9%. Subjects with prebooster anti-HBs titers of 1.0-9.9 mIU/mL had significantly higher postbooster anti-HBs titers than those with prebooster anti-HBs titers of <1.0 mIU/mL (P < 0.0001).

CONCLUSION

Having maternal HBeAg positivity is the most important determinant for HBsAg positivity in adolescents who received postnatal passive-active HB vaccination 15 years before. A significant proportion of complete vaccinees may have lost their immunological memories against HBsAg.

Impact of neonatal hepatitis B vaccination programme on age-specific prevalence of hepatitis B infection in teenage mothers in Hong Kong

We examined the impact of the neonatal hepatitis B immunization programme, first provided to all neonates born to mothers screened positive for hepatitis B surface antigen (HBsAg) in late 1983, on the age-specific prevalence of HBsAg carriage in teenage mothers managed in 1998–2008. HBsAg carriage was found in 2.5%, 2.7%, 8.8% and 8.0% of mothers aged ≤ 16, 17, 18, and 19 years, respectively (P=0.004), which was also correlated with advancing age (P=0.011). While neither difference nor correlation with age was found in mothers born before 1984, the prevalence of 1.2%, 1.5%, 7.1% and 8.3%, respectively, was significantly different among (P=0.008) and correlated with (P=0.002) age in mothers born 1984 onwards. Regression analysis indicated there was a significantly higher incidence of HBsAg carriage from age 17 onwards (adjusted odds ratio 2.55, 95% confidence interval 1.07–6.10, P=0.035), suggesting that the protective effect of the vaccine declined in late adolescence.

The impact of alcohol on BCG-induced immunity against Mycobacterium tuberculosis

BACKGROUND

Alcoholics are at heightened risk for developing active tuberculosis. This study evaluates chronic alcohol consumption in a murine model of vaccination with Mycobacterium bovis Bacille Calmette-Guèrin (BCG) and subsequent pulmonary infection with virulent Mycobacterium tuberculosis.

METHODS

BALB/c mice were administered the Lieber-DeCarli liquid ethanol diet or pair-fed the liquid control diet for 3 weeks either before or after subcutaneous vaccination with M. bovis BCG. At least 3 weeks after BCG vaccination, groups of mice on the aforesaid diets were challenged with intratracheal infection with M. tuberculosis H37Rv. Lung mycobacterial burden, and lung and lung-associated lymph node CD4(+) lymphocyte production of tuberculosis-specific interferon (IFN)-γ were assayed. Popliteal lymph node lymphocytes from both dietary regimens undergoing BCG vaccination (in the absence of M. tuberculosis infection) were also evaluated for purified protein derivative-induced IFN-γ production by ELISpot assay.

RESULTS

Mice begun on alcohol prior to vaccination with M. bovis BCG demonstrated impaired control of pulmonary challenge with virulent M. tuberculosis, as well as impaired lung CD4(+) and popliteal lymph node T-cell IFN-γ responses. If BCG vaccination was delivered prior to initiation of alcohol feeding, the mice remained protected against a subsequent challenge with M. tuberculosis, and BCG-induced immunity was not impaired in either the lung or the popliteal lymph nodes.

CONCLUSIONS

Alcohol consumption blunts the development of the adaptive immune response to M. bovis BCG vaccination, which impairs the control of a secondary challenge with M. tuberculosis, but only if the alcohol exposure is begun prior to BCG vaccination. These results provide insight into mechanisms by which alcohol consumption impairs antimycobacterial immunity, including in response to vaccination and subsequent pathogenic challenge.

Waning immunity and booster responses in nursing and medical technology students who had received plasma-derived or recombinant hepatitis B vaccine during infancy

BACKGROUND

The national hepatitis B virus (HBV) vaccination program was launched in Taiwan in 1984. After November 1992, a recombinant HBV vaccine replaced the plasma-derived HBV vaccine.

METHODS

A total of 1,812 nursing and medical technology freshman students was tested to evaluate their waning immunity toward hepatitis B. In the 2007 (2008) academic year, 438 (382) students testing nonprotective antibodies received 3 (1) booster doses of HBV vaccine according to suggestions from Taiwan's Center for Disease Control (CDC).

RESULTS

The seroprevalences of hepatitis B surface antigen (+) were 0.8% and 0.7% in the plasma-derived and recombinant group, respectively; for antibody to hepatitis B surface antigen (anti-HBs) (+), they were 43.2% and 33.3% (P < .001), respectively. In the 2007 freshman group, 99.1% of the students previously vaccinated with plasma-derived HBV vaccine exhibited anti-HBs seroconversion. In the 2008 freshman group, the booster dose induced anti-HBs seroconversions of 92.1% and 95.9% in the students who had received the plasma-derived and recombinant HBV vaccine, respectively (P = .370).

CONCLUSION

Most students exhibited signs of immune memory after receiving the booster, regardless of having received plasma-derived or recombinant HBV. Only a small number of vaccinees lost their immune memory after 16 years, suggesting that some students might benefit from boosting before proceeding to clinical practice.

Antibody response following hepatitis B vaccination in dialysis patients: does depression and life quality matter?

Previously, it was demonstrated that antibody production against hepatitis B virus (HBV) surface antigen (anti-HBs) achieved in hemodialysis patients is suboptimal. Decreased health-related quality of life (HRQOL) and depression is common among hemodialysis patients. This study evaluated whether HRQOL and depressive behavior are associated with antibody response against HBV surface antigen in hemodialysis patients. Depressive symptoms and HRQOL were assessed by Beck Depression Inventory (BDI) and Medical Outcomes Study Short Form (SF-36), respectively. Patients were separated into non-seroconversion (anti-HBs antibody titers <10 IU/L) and seroconversion (anti-HBs antibody titers > or =10 IU/L) groups. Among 188 patients, 37 (19.7%) were diagnosed as nonresponsive to vaccination (anti-HBs antibody titers <10 IU/L). Anti-HBs response is positively associated with Physical Component Summary Score of SF-36 (odds ratio: 1.44; P: 0.009) and albumin (odds ratio: 10.615, P: 0.007), and negatively with BDI score (odds ratio: 0.903, P: 0.007). We concluded that HRQOL and depression is closely related with antibody response following HBV vaccine in hemodialysis patients.

HLA and response to booster hepatitis B vaccination in anti-HBs-seronegative adolescents who had received primary infantile vaccination

To explore contemporarily genetic and non-genetic determinants of long-term immunological memory to hepatitis B (HB) vaccination, we conducted a case-control study nested in an adolescent cohort of booster recipients who had received primary infantile HB vaccination but with residual anti-HBs titers <10 mIU/mL at 15-18 years of age. High-resolution phenotypes of human leukocyte antigen (HLA)-A, -B, and -DRB1 loci were determined by sequence-specific oligonucleotide probe hybridization. After controlling for pre-booster anti-HBs levels, the absences of HLA-A*02 and -DRB1*08, simply expressed as A*02(-) and -DRB1*08(-), and the presence of B*15 were significantly associated with elevated risks of non-response (post-booster anti-HBs titers<10 mIU/mL) to booster vaccination. The adjusted odds ratios (ORs) were 3.85 (CI, 1.82-8.33), 4.55 (CI, 1.23-16.67), 3.59 (CI, 1.40-9.17), respectively. There was multiplicative synergism between A*02 and B*15 on the risk of non-response to booster vaccination. The multivariate-adjusted ORs for A*02(-)/B*15, A*02(-)/B*15(-), A*02/B*15, and A*02/B*15(-) haplotypes were 20.39 (p=0.0003), 3.29 (p=0.007), 1.32 (p>0.05), and 1.0, respectively. Recent cigarette smoking and/or betel-quid chewing was associated with a 12-fold risk of non-response to booster vaccination. Further comparisons between responders and adolescents who had undetectable post-booster anti-HBs titers (<0.1 mIU/mL) demonstrated similar results. Our results indicated that response to booster HB vaccination as well as long-term immunological responses to HB vaccination are closely related with host genetic factors, and probably modified by recent substance use.