Doses Of HBV Vaccine Research Articles

Hepatitis B immunity in adolescents and necessity for boost vaccination: 23 years after nationwide hepatitis B virus vaccination program in Taiwan

The first universal hepatitis B vaccination program for newborns in the world was launched in Taiwan in July 1984. Most studies on the effectiveness of hepatitis B vaccination focused on the seroprevalence of HBs Ag among children under 14 years old. Only few studies focused on the seropositivity of anti-HBs among adolescents aged 15–18 years old. The present study aimed to evaluate the impact of the nationwide hepatitis B vaccination program on the immunity to HBV infection and the necessity of boost among adolescents. In this study including eight annual seroprevalence surveys from 2000 to 2007, 2342 college entrants (1589 15-year-olds in group I and 753 18-year-olds in group II) and 1851 university freshmen (18-year-olds in group III) participated. Subjects identified anti-HBs, HBs Ag and anti-HBc negative were given boost three doses of HBV vaccine. The HBs Ag seroprevalence was 11.6%, 3.5% and 1.0% for participants who were born before 1984, 1984–1986 and after 1986. The anti-HBs-seropositive rates were significantly higher in group II (83.1%) than in group I (53.0%) and group III (53.5%). All 572 participants who were seronegative for anti-HBs, HBs Ag and anti-HBc became anti-HBs-seropositive after catch-up vaccination. It is concluded that the anti-HBs-seropositive rate decreased to 50% in 15 years after vaccination, and boost vaccination was 100% effective. The necessity and age for boost among anti-HBs negative adolescents and the timing of the first immunization should be further evaluated.

Investigation (In Vivo and In Vitro) of Booster Dose Vaccine Requirement for Long-Term Protection against Hepatitis B Virus Infection

Aim: Studies have shown that no booster dose was required at least 10 to 15 years after a primary vaccination for individuals who developed protective anti-hepatitis B surface (anti-HBs) antibodies. In this study, booster dose requirement for HBV after primary immunization was investigated. Materials and Methods: Seventeen individuals vaccinated previously were enrolled in the study. They had once developed a protective level of anti-HBs antibody after immunization and their anti-HBs titer had declined to an underprotective level. Twenty uninfected and unvaccinated healthy people were chosen as controls. Lymphoproliferative response to in-vitro stimulation with hepatitis B surface antigen (HBsAg) and anti-HBs response to vaccine were evaluated for immune response. Results: T lymphocytes from 4 (24%) of the study group showed lymphoproliferative response to HBsAg stimulation while none of the controls did (P < 0.05). In all subjects in the study group, anti-HBs response (>= 10 mIU/ml) was detected 1 to 7 days after the booster injection but in only 2 of the controls antibody response was detected 28 days after the first dose of HBV vaccine (P < 0.0001). Conclusions: A booster dose of HBV vaccine might not be required because of immunological memory.

Serologic response to hepatitis B vaccine with high dose and increasing number of injections in HIV infected adult patients

Sixty-five HIV-infected patients received high-dose (40 μg), short interval HBV vaccine. In non-responders to the initial immunization, 1–3 boosters were administered. Rate of response was 60.0% after primary vaccination, and 89.2% after boosters. However, 12 and 24 months after the last vaccination, only 63% and 32.7% of the responders, respectively, had persistence of protective anti-HBs titers (≥10 IU/L). The results of logistic regression show that gender, CD4 count, and HIV viral load were significant predictors of vaccination outcome. This study suggests that in HIV-infected patients with relatively high CD4 count, response to high dose of HBV vaccine is suboptimal. Rate of response may be increased by vaccine boosts, but antibody titers are significantly lower in non-responders than in responders to primary vaccination. Since persistence of anti-HBs titers appears significantly related to antibody titers after the immunization procedure, monitoring of anti-HBs, particularly in patients with low level of protective antibody titers after primary vaccination or boosters, seems more than justified.

S17. Cancer prevention by vaccination against hepatitis B

Chronic inflammation caused by persistent infection is closely related to a number of cancers; these include hepatitis B (HBV) or C and hepatoma, human papilloma virus and cervical cancer, and Helicobacter pylori and gastric cancer. The first evidence of cancer prevention by vaccination in humans was provided by HBV vaccination in infants. Chronic HBV is related to approximately 60%–90% of hepatocellular carcinomas (HCC) in adults and nearly 100% of childhood HCC in areas endemic for HBV infection. The first universal HBV vaccination program was launched in Taiwan and has continued for more than 20 years. Three or four doses of HBV vaccine were given to all infants starting from the first week of life. In addition, infants of high-risk mothers (with positive hepatitis B e antigen or high HBsAg titers) were given hepatitis B immunoglobulin within 24 h after birth. At 20 years after the launch of the HBV vaccination program in Taiwan, chronic HBV infection (HBsAg seropositive) rates in the general population below 20 years of age have revealed a remarkable reduction from 10%–17% before the vaccination program to 0.7%–1.7% after the program. HCC incidence rate in children 6–14 years old also fell from 0.52–0.54 to 0.13–0.20 per 100,000 (R.R.=0.25–0.36). HCC prevention failure is mainly related to vaccine failure to prevent chronic HBV infection. The causes of vaccine failure have included intrauterine infection, vaccine escape mutants, genetic hyporesponsive-ness, and poor compliance. Future efforts to reduce vaccine failure will improve the efficacy of liver cancer prevention by HBV vaccination. The experience of HCC prevention by HBV immunization may be applied to the prevention of other infection-related cancers.

Long Term Effects of One or Two Doses of Hepatitis B Vaccine in Adults After Five Years

The aim of this study is to evaluate hepatitis B vaccine protection in those adults who have taken one or two does of vaccine before. It was a retrospective cross sectional study was conducted on fifty-six military personnel in Tehran, Iran in the spring 2007. Demographic data such as age, marital status, education level, number of vaccine doses injected and, type of vaccine and date of last vaccination was collected. Their serum was tested for HBs Ab, HBc Ab and HBs Ag and finally the results were analyzed by SPSS software. All individuals were male with the mean age of 33.9+/-8.9 years. Twelve individuals who had only received one dose of injected vaccine had no antibody against HBsAg and no protection against hepatitis B virus. Of forty-four individuals that had received two doses of injected vaccine, 27 persons (61.4%) were protected and had serum HBsAb more than 10 MIU mL(-1). In conclusion one dose of HBV vaccine cannot produce immunity for five years but two doses of HBV vaccine can produce immunity for five years. However, HBsAb should be tested to make sure of immunity.

Similar long-term vaccine efficacy of two versus three doses of HBV vaccine in early life

WHO currently recommends three vaccinations against hepatitis B to provide optimal protection against infection and carriage. However, immunological theory and mathematical modelling suggest that similar protection could be induced with two doses, and trials among adolescents and adults have shown comparable rates for both primary seroprotection and geometric mean titres following vaccination. We determined vaccine efficacy among 60 children who only received two doses of hepatitis B vaccine as infants and among 463 children who had received three doses after 4–7 years of follow-up. Vaccine efficacy among the two-dose group was 86.3% against anti-HBc positivity (infection) and 92.3% against HBsAg positivity (carriage), which was similar to the vaccine efficacy found among the participants who had received three doses. To confirm this comparable vaccine efficacy a randomised controlled non-inferiority trial with long-term follow-up is needed.

Doubling the dose of recombinant HBV vaccine in patients with HIV

Doubling the dose of recombinant HBV vaccine in patients with HIV

Hepatitis B virus vaccination of blood donors – what costs may be expected?

Although the risk of transfusion-transmitted hepatitis B virus (TT-HBV) infection is very low, it still exists. Therefore, introduction of further precautions to reduce this risk is discussed at present. However, so far no data are available about the HBV vaccination status among blood donors (BDs). We compared HBV vaccination status of apheresis donors (ADs) of a university based and whole BDs (WBDs) of a Red Cross blood donation service using a standardized questionnaire. On the basis of these data, the estimated costs over 10 years for HBV vaccination were calculated for two different strategies and compared with the costs for HBV nucleic acid amplification technology (NAT) testing. 22.3% of the WBDs and 41.2% of the ADs indicated having received at least one HBV vaccine dose. This difference was related to the different demographic structures of the two BD populations (BDPs). With regard to the primary costs for the blood donation service, HBV vaccination of BDs could be an alternative to HBV NAT testing, especially for BDPs with an already high HBV vaccination rate and a high donation frequency.

A comparison of responsiveness to hepatitis B vaccination in patients on hemodialysis and peritoneal dialysis

The doses of hepatitis B vaccine given to peritoneal dialysis (PD) patients are currently based on responsiveness data from hemodialysis (HD) patients. To determine whether the doses are also appropriate from PD patients, we did a head-to-head comparison of short-term and 2-year responses to hepatitis B vaccination of HD patients and PD patients. We evaluated serum titers of the antibody to hepatitis B surface antigen (anti-HBs) after the patients had completed a course of four consecutive intramuscular vaccinations (40 μg of Engerix-B administered into the deltoid muscle at 0, 1, 2, and 6 months) in 69 dialysis patients (47 HD and 22 PD patients) who were both hepatitis B surface antigen (HBsAg) and anti-HBs negative. No patients had received a hepatitis B vaccination prior to the study. There was no significant difference in response to hepatitis B vaccination between the HD and PD groups (78.7% versus 77.3%, p = 0.33). The seroconversion rate defined as anti-HBs ≥ 10 IU/L was influenced only by age ( p = 0.011). There was also no significant difference in responsiveness between the HD and PD groups (60% versus 50%, p = 0.41) at a 2-year follow-up. We conclude that doses of HBV vaccine being used for HD patients are also appropriate for PD patients and a booster dose of vaccine is required to maintain seroprotection for those who lost protecting anti-HBs.

Hepatitis B immunization in low birthweight infants: do they need an additional dose?

Aim: To determine the influence of gestation and weight on the development of protective anti‐HB levels and geometric mean titres after three doses of HBV vaccine and to ascertain the need for a fourth dose in low birthweight infants. Methods: Hepatitis B vaccine (Enivac HB, Panacea Biotec Ltd., India) was given to 82 preterm (PT) and 60 term intrauterine growth‐retarded (T‐IUGR) infants at birth and at 6, 10 and 14 wk of life. Results: Protective anti‐HB levels (&gt;10 mIU/ml) were reached in 86.6% (71/82) of PT infants and 96.7% (58/60) of T‐IUGR infants after three doses of HBV vaccine (p= 0.044). The odds of having a protective response after the third dose of HBV vaccine was 1.25 (95% CI 1.02–1.53) with every one‐week increase in gestation (p= 0.032). Birthweight was not associated with the development of a protective immune response. After the third dose, only 66.7% (8/12) of the PT infants whose mothers had anti‐HB antibodies, developed protective anti‐HB levels compared with 90% (63/70) of those with no maternal antibodies (p= 0.028). In PT infants after the fourth dose, there was a significant increase in the proportion of infants with protective antibody levels (8.6%, 95% CI 0.6–16.6%) among those with no maternal antibodies and 12.2% overall (95% CI 6.0–21.3) (p= 0.031 to 0.002) over that reached with the third dose. Administration of the fourth dose to T‐IUGR infants did not confer such a benefit. Conclusion: In HBV‐endemic areas, PT infants, irrespective of their birthweights, may benefit from an additional dose of hepatitis B vaccine in a schedule starting at birth. This approach will prevent vertical transmission and bring their immune response up to par with term infants. Term intrauterine growth‐retarded infants should be vaccinated as per the schedule recommended for normal term infants. However, studies in other settings with different vaccine formulations and a longer follow‐up period will be required before this strategy can be practised more widely.

Immune status and the immune response to hepatitis B virus vaccine in thalassemic patients after allogeneic bone marrow transplantation.

We evaluated the immune status with respect to HBV and the immune response to readministration of HBV vaccine in a series of 20 patients with homozygous beta-thalassemia, aged 6-23 years (mean age: 13.0 +/- 4.2) who had undergone allogeneic bone marrow transplantation (BMT). Thirteen of them (group A), had received three doses of plasma-derived HBV vaccine from 7 to 5 years before BMT and 4-5 weeks after the last dose of vaccine, they had had high serum levels of HBV antibodies (anti-HBs). The remaining seven patients (group B) had had clinical symptoms and laboratory evidence of HBV infection in childhood with markedly elevated serum of anti-HBs. Before revaccination, a significantly lower percentage of patients (P < 0.005) with seropositive levels of anti-HBs was observed in group A than in group B. After administration of the second dose of HBV vaccine the percentage of subjects with protective levels of anti-HBs rose to 100% in both groups of patients even if the geometric mean of titers of anti-HBs increased more significantly in group B patients than in group A. We conclude that the serum levels of anti-HBs afforded by HBV vaccine administered from 7 to 5 years previously are very low and probably non-protective in most beta-thalassemic patients after allogeneic BMT, and that at least two doses of HBV vaccine should be readministered from 18 to 24 months after BMT to achieve adequate and long-term protection from HBV.

Seroconversion after Additional Vaccine Doses to Non-responders to Three Doses of Intradermally or Intramuscularly Administered Recombinant Hepatitis B Vaccine

Hospital staff members who failed to respond (anti-HBs < 10 IU/l) after 3 doses of a recombinant hepatitis B (HBV) vaccine (given either as 20 micrograms intramuscularly (n = 8) or 2 micrograms intradermally (n = 15)) received 1 or 2 additional doses by the same route as the initial vaccination. After the first additional dose, 12/23 responded with anti-HBs levels > or = 10 IU/l and after the second, another 2/5 responded, corresponding to a total response rate of 61%. No significant difference was seen in the response rate according to vaccination route, gender, age, or whether the vaccinee was a smoker or not. In this limited study some 50% of non-responders to 3 intradermal or intramuscular doses of recombinant HBV vaccine seroconverted after an additional 1-2 doses given by the same route as the initial vaccination, suggesting that additional doses can be administered by the same route as the initial one.

Mass Protection Program of Perinatal Hepatitis B Virus Infection in Japan and Impact of an Optional Booster Vaccination on Its Efficacy

We assessed the efficacy of a government-sponsored mass protection program in Osaka, Japan, for perinatal HBV infection in infants born to HBeAg positive HBV carrier mothers. We also evaluated the impact of optional follow-up procedures in such infants, including an evaluation of anti-HBs response and a booster dose of HBV vaccine for poor responders. The results demonstrated that this mass protection program protected 94.4% of the infants from perinatal HBV infection in the Osaka area. However, the proportion of infants with an unprotective level of anti-HBs was higher in the standard group than in the follow-up group both at 1.0 and 1.5 years of age, which was also the case for HBV events. Furthermore, the present study showed that a booster dose of vaccine in poor responders was very effective in promoting an anti-HBs response. In conclusion, we recommend that a follow-up blood test to confirm a response of anti-HBs to HBV vaccine should be performed at 4-8 weeks after the third injection of HBV vaccine in infants born to HBeAg positive HBV carrier mothers. We also recommend that a booster injection of HBV vaccine should be immediately given to poor responding infants who otherwise are at a considerable risk of developing HBV infection in late infancy.

Prevention of Neonatal HBV Infection with the Combination of HBIG and HBV Vaccine and Its Long‐Term Efficacy in Infants Born to HBeAg Positive HBV Carrier Mothers

Seventy-three infants born to HBeAg positive HBV carrier mothers were protected from neonatal HBV infection with our standard prevention schedule consisting of two doses of HBIG (0,2 mo) and three doses of HBV vaccine (2, 3, 5 mo). In 62 infants who successfully responded to HBV vaccine with a titer of anti-HBs greater than 2(3), anti-HBs titer was monitored for as long as 48 months (25.6 +/- 11.0 mo) and found to decrease as follows: 5.1 +/- 1.7 at 12 mo., 4.5 +/- 1.8 at 18 mo., 4.2 +/- 1.8 at 24 mo., 4.0 +/- 1.6 at 30 mo., 3.7 +/- 1.7 at 36 mo., 3.2 +/- 2.0 at 48 mo. During the follow-up period, eight HBV events (11.9%) were demonstrated: one case showed an increase of anti-HBs, three showed a reappearance of anti-HBc alone, three showed a reappearance of anti-HBc with increase of anti-HBs, and one became a chronic HBV carrier. All infants were further divided into three groups by their maximal response of anti-HBs to HBV vaccine: Group I (greater than or equal to 2(6)), Group II (2(3)-2(5)), and Group III (2(2) greater than or equal to). Group I sustained a higher titer from 12 to 30 months of age and had less HBV events than G-II and G-III. Our study suggests that acquisition of a high titer of anti-HBs is important in long-term prevention of HBV infection as well as in the neonatal period in infants born to HBeAg positive HBV carrier mothers.

Crime and human nature : by James Q. Wilson and Richard J. Herrnstein Simon and Schuster (Rockfeller Center, 1230 Avenue of the Americas, New York, New York 10020), 1985, 639 pp., hardcover —$22.95

In 2016, more than 600,000 persons were being held in EU/EEA correctional facilities on a given day. People in prison may be at risk of vaccine-preventable diseases. While vaccination recommendations for people in prison exist, little is known on coverage and implementation options.We performed a systematic review on existing evidence on vaccination in prison settings in the EU/EEA. We searched peer-reviewed and grey literature following international methodology and reporting standards, to gather records published between 1980 and 2016 in all languages. We analysed quantitative (acceptance, uptake, cost-effectiveness) and qualitative (barriers) outcomes.Out of 7041 identified records, 19 full-text articles were included from peer-reviewed literature and two from grey literature. Of these, 18 reported on hepatitis A and/or B virus (HAV/HBV), two on influenza and one on MMR vaccination. Two studies on HAV vaccine reported varying acceptance (5–91%) and uptake rates (62.9–70.5%). Seven studies reported on HBV vaccination. A comparative study showed a significantly higher uptake of the third HBV vaccine dose with the very rapid (63%) compared to the standard schedule (20%). HBV vaccination was generally well accepted (54–100%), whereas uptake was variable (dose 1:23–100%, dose 2:48–92%, dose 3:19–80%). One study on the combined HAV/HBV vaccine reported an acceptance rate of 34%, and declining uptake following dose 1. One study on influenza vaccine showed an uptake of 42–46%, while another reported a MMR vaccine acceptance of 80% and an uptake of 74%. Overall, main reasons for non-vaccination included release from/or transfer between prisons, and refusal.This systematic review highlighted important knowledge gaps and operational challenges for vaccination in prison settings. Vaccination is an effective measure that warrants comprehensive and tailored implementation to reduce the preventable disease burden, avoid risks of large outbreaks of vaccine-preventable diseases, and contribute to health equity for people in prison.