Schedules for hepatitis B vaccination of risk groups: balancing immunogenicity and compliance

Epidemiological and molecular characterization of HBV and HCV infections in HIV-1-infected inmate population in Italy: a 2017-2019 multicenter cross-sectional study

HBV/HCV co-infection is common in HIV-1-infected prisoners. To investigate the characteristics of HIV co-infections, and to evaluate the molecular heterogeneity of HIV, HBV and HCV in prisoners, we carried-out a multicenter cross-sectional study, including 65 HIV-1-infected inmates enrolled in 5 Italian detention centers during the period 2017-2019. HIV-1 subtyping showed that 77.1% of inmates were infected with B subtype and 22.9% with non-B subtypes. Italian nationals were all infected with subtype B (93.1%), except two individuals, one infected with the recombinant form CRF72_BF1, and the other with the HIV-1 sub-subtype A6, both previously not identified in inmates of Italian nationality. Non-Italian nationals were infected with subtype B (52.6%), CRFs (36.8%) and sub-subtypes A1 and A3 (5.2%). HIV variants carrying resistance mutations to NRTI, NNRTI, PI and InSTI were found in 7 inmates, 4 of which were never exposed to the relevant classes of drugs associated with these mutations. HBV and/or HCV co-infections markers were found in 49/65 (75.4%) inmates, while 27/65 (41.5%) showed markers of both HBV and HCV coinfection. Further, Italian nationals showed a significant higher presence of HCV markers as compared to non-Italian nationals (p = 0.0001). Finally, HCV phylogenetic analysis performed in 18 inmates revealed the presence of HCV subtypes 1a, 3a, 4d (66.6%, 16.7% and 16.7%, respectively). Our data suggest the need to monitor HIV, HBV and HCV infections in prisons in order to prevent spreading of these viruses both in jails and in the general population, and to implement effective public health programs that limit the circulation of different genetic forms as well as of viral variants with mutations conferring resistance to treatment.

Sero-prevalence of hepatitis B virus and compliance with hepatitis B vaccination schedules among outpatient clinic attendees in Nairobi

BACKGROUND

Hepatitis B is becoming a growing public health problem in Kenya. To combat the threat, HBV vaccination should be recommended, particularly for individuals who are not covered by the national immunization program. Vaccination provides sero-protection rates approaching 95% among healthy adults after completing the three-dose vaccination course, but decreases to 87% among those who receive only two doses, emphasizing the importance of completing the three-dose vaccination course. However, data on adult adherence to HBV multi-dose vaccines in Sub-Saharan Africa are limited, despite the fact that this information is critical for prevention. As a result, more research on HBV vaccine dose completion is required. The purpose of this study is to estimate the prevalence of hepatitis B virus infection among out-patient clinic attendees in Nairobi, Kenya, as well as to identify beneficiaries of free vaccination and barriers to completing the recommended vaccine doses.

METHODS

Between July 30th and September 30th, 2015, 2644 outpatient clinic attendees aged ≥ 4 were recruited from three hospitals in Nairobi County, Kenya: Mama Lucy, Riruta, and Loco. Self-administered questionnaires were used to collect socio-demographic information, and blood samples were tested for hepatitis B surface antigen (HBsAg) using the KEMRI HEPCELL Rapid® (Hepatitis B Detection kit) test kit. Individuals who tested negative for HBsAg were given a free course of three doses of HBV vaccine. The vaccination register provided information on the number of doses administered.

RESULTS

The average age of the study population was 31.4 years (range: 4-66), with females accounting for 59.2%. 1.82% (48/2644) of the participants tested positive for HBsAg. Among the 2596 individuals eligible for vaccination, 66% (1720/2596) received at least one dose, and 51.8% (1345/2596) received all three doses. Vaccination acceptance increased with age, with older patients more likely to return for subsequent dose (OR>1 for second and third dose). Unavailability and failure to contact client were cited as significant (p<0.0001) barrier to vaccination completion by 53.7% (666/1226, 95% CI 0.5-0.6) and 37% (454/1226, 95% CI 0.3-0.4) of respondents respectively.

CONCLUSION

The prevalence of HBV infection among outpatient clinic attendees highlights the importance of expanding HBV immunization programs in Kenya. However, given the low vaccination completion rate, there is a need for public awareness of the vaccine's importance in preventing HBV and HBV-related complications.

Viral Hepatitis - The Road Traveled and the Journey Remaining

Hepatitis is defined as inflammation of the liver and is commonly due to infection with The hepatotropic viruses - hepatitis A, B, C, D and E. Hepatitis carries one of the highest disease burdens globally and has caused significant morbidity and mortality among different patient populations. Clinical presentation varies from asymptomatic or acute flu-like illness to acute liver failure or chronic liver disease, characterized by jaundice, hepatomegaly and ascites among many other signs. Eventually, this can lead to fibrosis (cirrhosis) of the liver parenchyma and carries a risk of development into hepatocellular carcinoma. Hepatitis B and C are most notorious for causing liver cirrhosis; in 2019, an estimated 296 million people worldwide had chronic hepatitis B infection and 58 million are currently estimated to have chronic hepatitis C, with 1.5 million new infections of both hepatitis B and C, occurring annually. With the help of latest serological biomarkers and viral nucleic acid amplification tests, it has become rather simple to efficiently screen, diagnose and monitor patients with hepatitis, and to commence with appropriate antiviral treatment. More importantly, the development of vaccinations against some of these viruses has greatly helped to curb the infection rates. Whilst there has been exceptional progress over the years in the management of viral hepatitis, many hurdles still remain which must be addressed in order to proceed towards a hepatitis-free world. This review will shed light on the origin and discovery of the hepatitis viruses, the global epidemiology and clinical symptoms, diagnostic modalities, currently available treatment options, the importance of prevention, and the journey needed to move forward towards the eradication of its global disease burden.

Two-year immune effect differences between the 0-1-2-month and 0-1-6-month HBV vaccination schedule in adults

Background

The short-term 0–1–2-month hepatitis B virus (HBV) vaccination schedule was previously implemented in the adult population; however, its long-term immune effect remains unclear. The present study aimed to investigate (1) the 2-month and 2-year immune effects of HBV vaccination and (2) the compliance rate between the 0–1–2-month and 0–1–6-month vaccination schedules in adults.

Method

A total of 1281 subjects tested for hepatitis B surface antigen HBsAg(−) and hepatitis B surface antibody (anti-HBs)(−) were recruited. Participants from two distant counties were inoculated with the hepatitis B yeast vaccine at 10 µg per dose, with vaccination schedules of 0, 1, and 2 months (n = 606) and 0, 1, and 6 months (n = 675); sequential follow-up was performed at 2 months and 2 years after the 3rd injection.

Results

There were no significant differences in the anti-HBs seroconversion rates between the those in the 0–1–2-month and 0–1–6-month vaccination schedule groups at 2 months (91.96% vs. 89.42%, p = 0.229) and 2 years (81.06% vs. 77.14%, p = 0.217). The quantitative anti-HBs level in those in the 0–1–2-month vaccination schedule group was not different from that in those in the 0–1–6-month vaccination schedule group at 2 months (anti-HBs₁) (342.12 ± 378.42 mIU/ml vs. 392.38 ± 391.96 mIU/ml, p = 0.062), but it was higher at 2 years (anti-HBs₂) (198.37 ± 286.44 mIU/ml vs. 155.65 ± 271.73 mIU/ml, p = 0.048). According to the subgroup analysis, the 0–1–2-month vaccination schedule induced better maintenance (p = 0.041) and longer reinforcement (p = 0.019) than the 0–1–6 vaccination schedule. The 0–1–2-month vaccination schedule group also had a higher 3rd injection completion rate (89.49% vs. 84.49%, p = 0.010).

Conclusion

The 0–1–2-month vaccination schedule was associated with a similar short-term immune effect and might induce better long-term immune memory and a higher completion rate in the adult population.

Trial registration None

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07151-6.

Undetectable Anti-HBs Antibodies: Need of a Booster Dose for HIV-1-Infected Individuals

HBV vaccination effectively prevents HBV transmission and the development of liver cancer. Disease progression and liver-related complications are more common in HIV-1/HBV co-infected than HBV mono-infected individuals. A considerable body of literature, which will be reviewed here, indicates that response to HBV vaccine is suboptimal in HIV-1-infected individuals and that the poor maintenance of protective immunity to HBV vaccines in these individuals is an important medical issue. Several factors affect HBV vaccine response during HIV-1 infection including CD4+ T cell counts, B cell response, vaccine formulation, schedules, and timing of antiretroviral therapy (ART). The initial response to HBV vaccination also plays a critical role in the sustainability of antibody responses in both HIV-1-infected and uninfected vaccinees. Thus, regular follow-up for antibody titer and a booster dose is warranted to prevent HBV transmission in HIV-1 infected people.

Microneedles with dual release pattern for improved immunological efficacy of Hepatitis B vaccine

In this study, dissolving microneedles (DMNs) with dual-release pattern, capable of both bolus release and slow release, were prepared. These DMNs were used with a hepatitis B vaccine that requires multiple shots to achieve immunological efficacy comparable to that obtained when two separate shots are administered. Dissolving microneedles with HBsAg in PLA tips and CMC coating formulation together (HBsAg-PLA/CMC-DMNs) consist of polylactic acid (PLA) tips for slow release, a carboxy-methyl cellulose (CMC) coating formulation for bolus release, and a dissolving base of polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) for dissolution in the skin. The in vitro release pattern of HBsAg from the CMC coating formulation and PLA tips was observed. Through an in vivo test, 1) the delivery efficiency of HBsAg-PLA/CMC-DMNs was observed, and 2) the immunological efficacy of this method was compared with the efficacy of two shots delivered by conventional intramuscular (IM) administration and two shots delivered by HBsAg-coated microneedle (CMNs) administration. HBsAg-PLA/CMC-DMNs punctured the skin successfully. The PVA/PVP base was completely dissolved within 10 min of insertion, resulting in the delivery of all microneedle tips into the skin. In the in vitro release experiment, all of the HBsAg in the CMC coating formulation was released within 20 min, and the HBsAg present in the PLA tips was gradually released over more than 55 days. The antibody titer of one shot of HBsAg-PLA/CMC-DMNs was the same as or higher than two shots delivered by conventional IM and CMN methods. DMNs with dual-release pattern can deliver two formulations simultaneously with a single shot, resulting in improved immunological efficacy of HBsAg that requires multiple doses. In addition, this dual-release MN system can be used for the delivery of other drugs that require multiple administrations.

Acceptability and tolerability of repeated intramuscular electroporation of Multi-antigenic HIV (HIVMAG) DNA vaccine among healthy African participants in a phase 1 randomized controlled trial

Introduction

Intramuscular electroporation (IM/EP) is a vaccine delivery technique that improves the immunogenicity of DNA vaccines. We evaluated the acceptability and tolerability of electroporation among healthy African study participants.

Methods

Forty-five participants were administered a DNA vaccine (HIV-MAG) or placebo by electroporation at three visits occurring at four week-intervals. At the end of each visit, participants were asked to rate pain at four times: (1) when the device was placed on the skin and vaccine injected, before the electrical stimulation, (2) at the time of electrical stimulation and muscle contraction, and (3) at 10 minutes and (4) 30 minutes after the procedure was completed. For analyses, pain level was dichotomized as either “acceptable” (none/slight/uncomfortable) or “too much” (Intense, severe, and very severe) and examined over time using repeated measures models. Optional brief comments made by participants were summarized anecdotally.

Results

All 45 participants completed all three vaccination visits; none withdrew from the study due to the electroporation procedure. Most (76%) reported pain levels as acceptable at every time point across all vaccination visits. The majority of “unacceptable” pain was reported at the time of electrical stimulation. The majority of the participants (97%) commented that they preferred electroporation to standard injection.

Conclusion

Repeated intramuscular electroporation for vaccine delivery was found to be acceptable and feasible among healthy African HIV vaccine trial participants. The majority of participants reported an acceptable pain level at all vaccination time points. Further investigation may be warranted into the value of EP to improve immunization outcomes.

ClinicalTrials.gov NCT01496989

Effectiveness Analysis of the Immunization Against Hepatitis B in Liver Transplantation Patients

OBJECTIVE

This article analyzes the effectiveness of a super-accelerated immunization schedule against hepatitis B in patients who have received a liver transplantation.

METHODS

This is a quantitative and retrospective study based on secondary data of medical records from 177 patients who have received a liver transplantation at the Hospital de Base in São José do Rio Preto, São Paulo State, Brazil, between 1998 and 2016.

RESULTS

From the total number of participants, 72.89% were male, 39.55% had a cirrhosis diagnosis with associated causes, 23.16% had hepatocellular carcinoma, 53.11% were classified according to Child-Turcotte-Pugh C score, 58.76% had the hepatitis C virus, 97.18% had received an unconventional immunization schedule, and seroconversion was 36.63% among those with an unconventional schedule. The fact that the patient had the hepatitis C virus was statistically significant considering the lack of protection of the vaccine against the hepatitis B virus; their chances were 5 times higher of not seroconverting at the end of the immunization schedule.

CONCLUSION

The need for high immediate protection in a short term may justify using unconventional immunization schedules in patients who make it to the transplantation waiting list without any previous immunization.

Hepatitis B vaccination and immunotherapies: an update

World Health Organization (WHO) estimates that 257 million people were living with chronic hepatitis B virus (HBV) infection. Highest HBV prevalence was found in the WHO Western Pacific Region (6.2%) and in the WHO African Region (6.1%). The HBV vaccine is the best protection against chronic HBV infection and its complications. Globally, routine infant immunization against HBV has increased with an estimated coverage of 84% in 2017. Nevertheless, in many countries further efforts are needed to implement this coverage and ensure national immunization programs for people at major risk for HBV infection. Therapeutic vaccination in chronic HBV infected patients can cause anti-HBV immune responses able to remove and/or cure infected hepatocytes. It shows promising results in murine model and human trials, but these results need to be consolidated by further multicenter clinical studies. In particular, the efficacy of therapeutic vaccine seems to improve by combination therapies.

Letter to the editor: female sex workers and HPV vaccine

When considering what the scientific evidence is for the potential added value to offer HPV vaccines to sex workers, not only its potential role for female sex workers should be examined, but its role for all those who conduct sex work. Our initial paper looked at the evidence in terms of HPV vaccine immunogenicity, efficacy, effect on transmission, induction of mucosal immunity, and not at implementation. Brown and Cabral considered our omission to address the aspects of implementation an 'academic mistake'. We disagree; implementation aspects are complex and require analyses of multiple barriers, and how to address these. It only makes sense to discuss these if there is scientific evidence for its implementation; otherwise offering the vaccine is not useful.

Screening for hepatitis B virus and accelerated vaccination schedule in prison: A pilot multicenter study

BACKGROUND AND AIM

Vaccine against hepatitis B virus (HBV) is highly effective in preventing HBV infection. The aims of this study were to (1) increase the epidemiological knowledge on the impact of HBV in Tuscany region prisons by registering the results of serum screening on a clinical medical record and (2) increase the anti-HBV vaccination using an accelerated schedule.

METHODS

Our study population was composed of all detainees present in prisons and all constrained from freedom or at institutions in the Tuscany region and not vaccinated at these facilities from 1 December 2016 to 31 May 2017.

RESULTS

Of 17 detention facilities in the Tuscany region, 15 were enrolled in the study. On 28 February 2017, there were 3068 detainees present in these institutions. Considering the 1075 subjects screened for HBV serum markers, 730 (67.9%) were susceptible to infection and needed to be vaccinated. Five hundred and ninety-six agreed to be vaccinated (82%); 27 (2.5%) of our subjects had an isolated anti-HBc, 20 (1.9%) were HBV infected (HBsAg+), 127 (11.8%) had previous HBV infection (anti-HBs+, anti-HBc+ and HBsAg-), and 171 had been previously vaccinated. Five hundred and fifty-five inmates (95.1%) received the first vaccine dose, and 404 (83%) underwent the third dose at day 21.

CONCLUSION

This study showed that of a high percentage of subjects who underwent screening, more than half needed to be vaccinated. Moreover, our study reached very high levels of vaccination coverage, considering both the entire enrolled population and the new inmates.

Short-term immunogenicity of standard and accelerated hepatitis B virus vaccination schedules in healthy adults: a comparative field study in China

World Health Organization recommends hepatitis B virus (HBV) immunization at 0, 1, and 6 months. However, studies have suggested that shortening the interval between the first and last HBV immunization can improve completion rates. Less clear is whether accelerated immunization is as immunogenic as standard immunization. Thus, the present study aimed to compare the short-term immunogenicity of yeast-derived hepatitis B vaccine in healthy adults immunized on an accelerated or standard schedule. Between June 2013 and March 2014, individuals from Jinfeng and Longmen, China were randomly assigned to receive the vaccine on an accelerated schedule (at 0, 1, and 2 months; n=201) or a standard schedule (at 0, 1, and 6 months; n=206). Subjects filled out a questionnaire asking about demographic and other health data, and they underwent physical examination. Blood was assayed for HBV surface antigen and HBV surface antibody (HBsAb) at 1–2 months after the three-dose schedule. Multivariate binary logistic regression was used to determine whether the rate of anti-HBs seroconversion differed with immunization schedule. Covariance analysis was used to compare geometric mean HBsAb concentration between the two schedules. The anti-HBs seroconversion rate was 84.6% in the accelerated group and 90.3% in the standard group. After controlling for several potential confounders, the accelerated schedule was associated with significantly lower anti-HBs seroconversion rate (OR: 0.560, 95% CI: 0.318–0.988). Similarly, the accelerated schedule was associated with significantly lower geometric mean HBsAb concentration. These results suggest that the standard schedule is more likely to lead to anti-HBs seroconversion and higher HBsAb levels in adults.

Predictors of hepatitis B vaccination completion among people who use drugs participating in a national program of targeted vaccination

BACKGROUND

Targeted vaccination strategies are necessary to prevent people who use drugs (PWUD) becoming infected with hepatitis B virus (HBV). The aims of this study were to provide an overview of the activities for PWUD in a decentralised vaccination program in the Netherlands and to explore the determinants associated with completing a standard hepatitis B vaccination series.

METHODS

We used data for behavioural risk groups from the register of the national vaccination program. The data concerned PWUD who were immunised against hepatitis B in the Netherlands between 2002 and 2011. A standard series of three vaccinations (at 0, 1, and 6 months) was offered at inclusion and was continued if serological markers for past or chronic HBV infection were absent. Completion of a vaccination series (at least three vaccinations, irrespective of timing) was a dependent variable in our logistic regression analysis.

RESULTS

The program reached 18,054 PWUD. Of the 15,746 participants eligible for vaccination (i.e. they were neither carriers of hepatitis B nor immune to hepatitis B), 9089 (58%) completed a series of three hepatitis B vaccinations. Factors associated with a higher completion rate of a vaccination series (p < 0.01) were: starting vaccination in the earlier years of the program, older age of PWUD, intravenous drug use, vaccine administration by addiction care centres, and flexibility in location of vaccine delivery.

CONCLUSION

Despite using a standard HBV vaccination schedule and no financial incentives, vaccination completion among PWUD was relatively high. Our results suggest that flexibility of vaccination location and administration of vaccines by healthcare workers with sustainable contact with PWUD could improve vaccination programs for this risk group.

Evaluation of a convenient vaccination schedule against hepatitis B in HIV-patients with undetectable HIV viral load

Vaccination against hepatitis B virus (HBV) is recommended for all HIV-positive individuals but the standard schedule is not satisfactory. High or more doses have also been studied with variable results. We compared a vaccination schedule with a higher dose but fewer shots to the standard scheme (HBVaxPro 40 μg versus Engerix 20 μg at 0, 1, and 6 months). Of the 63 patients vaccinated with HBVaxPro 79%, 65% and 47% seroconverted at month 1, 12 and 24 after vaccination, respectively. A total of 137 patients received Engerix and showed lower response rates (68%, 53% and 38%, respectively). Anti-HBs titers in the Engerix group were also lower with a statistically significant difference. In patients younger than 55 years HBVaxPro was 3 times more likely to provoke a response compared with Engerix (OR = 3, p = 0.006). In conclusion, HBVaxPro 40 μg at 3 doses could be proposed as a more robust and acceptable alternative.

Emerging Trends in Epidemiology of Hepatitis B Virus Infection

Although a vaccine against hepatitis B virus (HBV) has been available since 1982, the prevalence of adults with chronic HBV infection in sub-Saharan Africa and East Asia is still estimated at 5-10%. A high rate of chronic infections is also found in the Amazon and the southern parts of eastern and central Europe. In the Middle East and the Indian subcontinent, the prevalence is 2-5%. Less than 1% of the population of Western Europe and North America is chronically infected. Given the high prevalence of infections (such as hepatitis) among inmates, prison is considered a reservoir for facilitating such infections. Based on these premises, this current review examines and discusses emerging trends in the epidemiology of HBV infection, with particular attention to HBV infection in prison. The hepatitis B surface antigen (HBsAg) prevalence in prisoners in west and central Africa is very high (23.5%). The Centers for Disease Control and Prevention has highlighted the importance of HBV blood screening and subsequent anti-HBV vaccination in the prison population. The vaccination was recommended for all inmates, representing an opportunity to prevent HBV infection in a high-risk population. In these subjects, an accelerated hepatitis B immunisation schedule may result in rapid seroconversion for early short-term protection. Therefore, it is necessary to seek collaboration among public health officials, clinicians and correctional authorities to implement a vaccination programme.

Hajj vaccinations-facts, challenges, and hope

Vaccination is an effective preventive measure that has been used in the unique Hajj pilgrimage setting to control the transmission of infectious diseases. The current vaccination policy applied during Hajj is reviewed herein, highlighting the effectiveness of the approaches applied and identifying research gaps that need to be filled in order to improve the development and dissemination of Hajj vaccination strategies.

Shortened Intervals during Heterologous Boosting Preserve Memory CD8 T Cell Function but Compromise Longevity

Developing vaccine strategies to generate high numbers of Ag-specific CD8 T cells may be necessary for protection against recalcitrant pathogens. Heterologous prime-boost-boost immunization has been shown to result in large quantities of functional memory CD8 T cells with protective capacities and long-term stability. Completing the serial immunization steps for heterologous prime-boost-boost can be lengthy, leaving the host vulnerable for an extensive period of time during the vaccination process. We show in this study that shortening the intervals between boosting events to 2 wk results in high numbers of functional and protective Ag-specific CD8 T cells. This protection is comparable to that achieved with long-term boosting intervals. Short-boosted Ag-specific CD8 T cells display a canonical memory T cell signature associated with long-lived memory and have identical proliferative potential to long-boosted T cells Both populations robustly respond to antigenic re-exposure. Despite this, short-boosted Ag-specific CD8 T cells continue to contract gradually over time, which correlates to metabolic differences between short- and long-boosted CD8 T cells at early memory time points. Our studies indicate that shortening the interval between boosts can yield abundant, functional Ag-specific CD8 T cells that are poised for immediate protection; however, this is at the expense of forming stable long-term memory.

Optimizing hepatitis B vaccination in prison

OBJECTIVE

We aimed to establish the current status of hepatitis B virus (HBV) vaccination in prison.

METHODS

We carried out two evaluations within a 1-year interval with inmates incarcerated for 6 to 12 months. A monitoring process was introduced in-between the two evaluations.

RESULTS

We included 231 inmates. Overall, 42.9% were immunized because of a previous vaccination and 14.3% because of a previous exposure. Inmates born in an area of medium or high endemicity for HBV were significantly more exposed to HBV. The proportion of non-immunized inmates was 42.8% at the time of incarceration and 27.5% after 6 to 12 months. Vaccination coverage with two doses, after 6 to 12 months, was 63% among patients who were initially non-immunized.

CONCLUSION

The recently developed accelerated vaccination schedule should help improve HBV vaccination coverage.

Comparison of Accelerated and Standard Hepatitis B Vaccination Schedules in High-Risk Healthy Adults: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Selecting the most efficient vaccination schedule is an important issue.

OBJECTIVE

To assess the beneficial and harmful effects of accelerated hepatitis B vaccination schedules in high-risk healthy adults.

METHODS

We searched controlled trial registers of The Cochrane Library as well as MEDLINE, EMBASE, VIP Database for Chinese Technical Periodicals, and the Chinese National Knowledge Infrastructure databases for randomized controlled trials published up to December 2013 that compared accelerated hepatitis B vaccine schedules to the standard schedule in adults. The results were presented as relative risk with 95% confidence intervals. Fixed or random effect models were used for analysis.

RESULTS

We identified 10 randomized trials, all with one or more methodological weaknesses. Compared to the standard schedule, most accelerated schedules resulted in higher proportions of healthy vaccines more rapidly reaching anti-hepatitis B antibody levels >10 IU/L (P<0.05) initially and maintaining similar seroprotection rates after 6 months (P>0.05). Although accelerated schedules produced anti-hepatitis B levels higher than the standard schedule for the first month after the initial vaccine dose, they were significantly lower than the standard schedule after 6 months, except for an accelerated schedule that called for a fourth booster injection 12 months after the initial dose. Subjects administered accelerated vaccine schedules had similar compliance rate as those administered the standard schedule over the first 6 months of vaccination (relative risk = 1.00, 95% confidence interval: 0.84-1.21).

CONCLUSION

For rapid seroconversion and almost immediate short-term protection, accelerated vaccination schedules could be useful for at-risk groups. However, additional studies on the long-term protection and effectiveness of the primary doses of accelerated schedules are necessary.

Efficacy of an accelerated hepatitis B vaccination program during pregnancy

OBJECTIVE

To estimate the feasibility and immunogenicity of an accelerated hepatitis B vaccination schedule of 0, 1, and 4 months in high-risk pregnant women.

METHODS

We conducted a prospective clinical trial of high-risk pregnant women who were hepatitis B surface antigen-negative at presentation for prenatal care. A detailed questionnaire was administered and eligible women received a hepatitis B vaccine intramuscularly on a 0-, 1-, and 4-month schedule. Adverse reactions and hepatitis B surface antigen seroconversion rates were documented. Factors influencing seroconversion were determined.

RESULTS

Two hundred high-risk pregnant women were enrolled; 84% completed the three-dose vaccine series. Seroconversion (hepatitis B surface antigen 10 milli-international units/mL or greater) after one dose was 56% (95% confidence interval [CI], 49-63%), 77% (95% CI, 71-83%) after two doses, and 90% (95% CI, 85-94%) after completing three doses. Body mass index was inversely associated with seroconversion rates (P<.001). There was no single body mass index above which seroconversion did not occur. There were no serious adverse events; injection site discomfort was the most prevalent complaint (10.5%).

CONCLUSION

An accelerated hepatitis B vaccination schedule at 0, 1, and 4 months in high-risk pregnant women is effective, practical, and well tolerated. This accelerated vaccine strategy can be completed during the course of pregnancy and provides another means of decreasing hepatitis B virus disease and transmission.

Immunosenescence and herd immunity: with an ever-increasing aging population do we need to rethink vaccine schedules?

Vaccination is a powerful public health tool that has been of tremendous benefit in protecting vulnerable populations from specific infections. Moreover, in addition to the direct benefits to vaccinated individuals, the indirect effects of protection at the community level have also been demonstrated and termed 'herd immunity'. The predicted demographic shift in the population landscape towards an ever-increasing aging population and the evidence suggesting that older individuals produce less-than-optimal vaccine responses have raised the question of rethinking vaccine schedules. This article provides evidence that even if herd immunity might be an option to indirectly protect the aging and aged adult population, the highest priorities for the near future must be to understand how vaccine responses in older individuals can be improved, to break down the public, cultural, societal and political barriers to vaccination and to counter the antivaccination movement that inhibits the worldwide spread of lifelong immunization programs.

Hepatitis A/B vaccine completion among homeless adults with history of incarceration

Hepatitis B virus (HBV) vaccination rates for incarcerated adults remain low despite their high risk for infection. This study determined predictors of vaccine completion in homeless adults (N= 297) who reported histories of incarceration and who participated in one of three nurse-led hepatitis programs of different intensity. Moreover time since release from incarceration was also considered. Just over half of the former prisoners completed the vaccine series. Older age (≥40), having a partner, and chronic homelessness were associated with vaccine completion. Recent research has documented the difficulty in providing vaccine services to younger homeless persons and homeless males at risk for HBV. Additional strategies are needed to achieve HBV vaccination completion rates greater than 50% for formerly incarcerated homeless men.

Randomized trial of the immunogenicity and safety of the Hepatitis B vaccine given in an accelerated schedule coadministered with the human papillomavirus type 16/18 AS04-adjuvanted cervical cancer vaccine

The human papillomavirus type 16/18 (HPV-16/18) AS04-adjuvanted cervical cancer vaccine is licensed for females aged 10 years and above and is therefore likely to be coadministered with other licensed vaccines, such as hepatitis B. In this randomized, open-label study, we compared the immunogenicity of the hepatitis B vaccine administered alone (HepB group) or with the HPV-16/18 AS04-adjuvanted vaccine (HepB+HPV group) in healthy women aged 20 to 25 years (clinical trial NCT00637195). The hepatitis B vaccine was given at 0, 1, 2, and 12 months (an accelerated schedule which may be required by women at high risk), and the HPV-16/18 vaccine was given at 0, 1, and 6 months. One month after the third dose of hepatitis B vaccine, in the according-to-protocol cohort (n = 72 HepB+HPV; n = 76 HepB), hepatitis B seroprotection rates (titer of ≥10 mIU/ml) were 96.4% (95% confidence interval [CI], 87.5 to 99.6) and 96.9% (CI, 89.2 to 99.6) in the HepB+HPV and HepB groups, respectively, in women initially seronegative for anti-hepatitis B surface antigen (HBs) and anti-hepatitis B core antigen (HBc). Corresponding geometric mean titers of anti-HBs antibodies were 60.2 mIU/ml (CI, 40.0 to 90.5) and 71.3 mIU/ml (CI, 53.9 to 94.3). Anti-HBs antibody titers rose substantially after the fourth dose of hepatitis B vaccine. All women initially seronegative for anti-HPV-16 and anti-HPV-18 antibodies seroconverted after the second HPV-16/18 vaccine dose and remained seropositive up to 1 month after the third dose. Both vaccines were generally well tolerated, with no difference in reactogenicity between groups. In conclusion, coadministration of the HPV-16/18 AS04-adjuvanted vaccine did not affect the immunogenicity or safety of the hepatitis B vaccine administered in an accelerated schedule in young women.

Predictors of HAV/HBV vaccination completion among methadone maintenance clients

This randomized, controlled study (N = 256) was conducted to compare three interventions designed to promote hepatitis A virus (HAV) and hepatitis B virus (HBV) vaccination completion among clients undergoing methadone maintenance (MM) treatment. Participants were recruited from five MM treatment sites in Southern California and randomized into three groups: Motivational Interviewing-Single (MI-Single), Motivational Interviewing-Group (MI-Group); and Nurse-Led Hepatitis Health Promotion (HHP). All were offered the three-series HAV/HBV vaccine. A total of 148 participants completed the vaccine. Groups did not differ in rate of vaccination completion (73.6%, HHP group, vs. 65% and 69% for the MI-Single and MI-Group, respectively). The equivalence of findings across groups suggests the value of including nurses with a comprehensive health focus in promoting vaccination completion.

Audit of hepatitis B vaccination of men who have sex with men attending Scottish genitourinary medicine clinics

Practice related to hepatitis B vaccination of men who have sex with men (MSM) in Scottish genitourinary medicine clinics was audited against targets based on the offer and completion of vaccination set by the British Association of Sexual Health and HIV. Of 521 cases audited from 11 clinics, 215 (41%) were eligible for vaccination and 175 (81%) of eligible MSM were offered vaccination. Of those, 144 (82%) accepted vaccination. The super-accelerated schedule was most commonly prescribed but only 29% of those starting this schedule completed it, compared with 57% of those receiving the standard course. The overall vaccination completion rate was 31% and 82% of those completing vaccination had antisurface antibodies measured. A more robust recall system and uniformity in vaccination policies addressing the balance of patient compliance and immunogenicity of vaccine schedule are needed to improve completion rates.

Feasibility of completing an accelerated vaccine series for homeless adults

Homeless adults are at high risk for hepatitis B virus (HBV) infection. In addition to culturally sensitive programmes designed to enhance vaccination compliance, accelerated HBV vaccination (three doses over 21 days) have also been suggested to improve compliance among high-risk groups. In this paper, we examined predictors of completers of two of three doses of a HAV/HBV vaccine series, normally delivered over a 6-month period, to simulate compliance with an accelerated series, dosed over 4 weeks. A convenience sample of 865 homeless adults was randomized into a nurse case-managed approach (NCMIT) vs standard programmes with (SIT) and without tracking (SI). Each group was assessed for completion of two of the three dose HAV/HBV vaccine series as well as the full three dose vaccine series. Sixty-eight percent of the NCMIT participants completed the three dose vaccination series at 6 months compared to 61% of SIT participants and 54% of SI participants. Eighty-one percent of the NCMIT participants completed two of the vaccinations compared to 78% of SIT participants and 73% of SI participants. The NCMIT approach resulted in greater numbers of completers of two of three doses and of the full three dose vaccine series. Predictors of completers of two doses and the full three dose vaccine series are provided. A greater number of homeless persons completed two doses across the three groups compared to the three dose vaccine series. The use of nurse case-management and tracking, coupled with an accelerated HAV/HBV vaccination schedule, may optimize vaccination compliance in homeless adults.

Use of an accelerated immunization schedule for combined hepatitis A and B protection in the corporate traveler

Increased international business travel to moderate or high endemic areas of hepatitis A and B may leave many business travelers at risk for infection if not vaccinated. Many international business travelers depart for hepatitis A and B endemic areas within 2 months of the decision to travel. Many of these travelers do not seek pretravel medical advice and are unaware of the risks and modes of acquiring hepatitis A and B. Monovalent vaccines and a combined hepatitis A and B vaccine are available and can be administered on an accelerated schedule. Because many areas endemic for hepatitis A are also endemic for hepatitis B, accelerated administration of the combined vaccine can offer protection for many international business travelers destined for areas endemic for both diseases and should be part of corporate travel immunization programs.

The rhesus macaque pediatric SIV infection model - a valuable tool in understanding infant HIV-1 pathogenesis and for designing pediatric HIV-1 prevention strategies

Worldwide, the AIDS pandemic continues almost relentlessly. Women are now representing the fastest growing group of newly infected HIV-1 infected patients. The risk of mother-to-child-transmission (MTCT) of HIV-1 increases proportionally as many of these women are of childbearing age. The screening of pregnant women, the early diagnosis of HIV-1 infection, and the administration of antiretroviral therapy (ART) have helped to reduce MTCT significantly. However, this holds true only for developed countries. In many resource-poor countries, access to ART is limited, and breastfeeding, a major route of HIV-1 transmission, is essential to protect the infant from other infectious diseases preponderant in those geographic regions. HIV-1 infected children, in contrast to adult patients, have higher levels of virus replication that decline only slowly, and a subset progresses to AIDS within the first two years. Thus, it is imperative to understand pediatric HIV-1 pathogenesis to design effective prevention strategies and/or a successful pediatric HIV-1 vaccine. The review summarizes how MTCT of HIV-1 in humans can be modeled in the infant macaque model of SIV infection. Importantly, the infant macaque model of SIV infection provides the opportunity to study early virus-host interactions in multiple anatomic compartments. Furthermore, the review underlines the importance of evaluating SIV/HIV immune responses in the context of the normal developmental changes the immune system undergoes in the newborn. Thus, the pediatric SIV infection model provides a unique resource for preclinical studies of novel intervention therapies and vaccine strategies to stop MTCT of HIV-1.

Prevention of viral hepatitis (B and C) reassessed

As hepatitis B and C share modes of transmission, their combined occurrence is not uncommon, particularly in areas where both viruses are endemic and in individuals at high-risk of parenteral infection. Both viral hepatitis infections form an important global public health problem, responsible for over half a billion chronic infections worldwide. Their distinctive characteristics impact upon their epidemiology, transmission, and the success of the different prevention strategies. Since several decades a safe and effective vaccine has been available to prevent hepatitis B virus (HBV) infection. Universal vaccination is the cornerstone of global HBV control. Despite major success, vaccine uptake is hampered, and increasing efforts are required to eliminate acute and chronic hepatitis B. Unlike hepatitis C and HIV, HBV has not captured sufficient attention from policymakers, advocacy groups, or the general public: a major challenge for the future. Although progress has been made in the development of an hepatitis C vaccine, short-term successes are not expected. Even without a vaccine, successes can be reported in the field of hepatitis C due to e.g. implementation of universal precautionary measures in health-care settings, screening of blood and blood products, and identification and counselling of infected people. Despite important efforts, transmission in injecting drug users is increasing.

Benefits of early hepatitis B immunization programs for newborns and infants

Despite the availability of safe and effective hepatitis B virus (HBV) vaccines for >20 years, strategies targeting risk groups failed to sufficiently control hepatitis B disease at the population level; this is mainly because of difficulties in risk identification and in program implementation. Hence, the global burden of disease of HBV still is substantial. The World Health Organization recommends universal vaccination against hepatitis B to ultimately eliminate HBV; this recommendation had been progressively implemented to reach 168 countries with a universal program by the end of 2006. However, hepatitis B immunization is currently becoming endangered of losing its place on the agendas of governments, agencies, and international organizations, mainly because of the increasing success of these immunization programs and the interest in newer vaccine-preventable diseases and the related programs.This publication aims to show that vaccination programs targeting newborns and infants are preferable to achieve this goal. The benefits of universal HBV vaccination for newborns and infants are: higher impact on chronic carrier rate and transmission; established potential of high vaccine coverage in this age group; opportunities to combine HBV vaccination with existing universal vaccination programs for newborns and infants; and impact on perinatal transmission, if vaccination is started shortly after birth. Moreover, the safety, immunogenicity, and long-term efficacy of newborn and infant HBV vaccination have been proven extensively. In summary, newborn and infant HBV vaccination programs should be considered the preferred strategy, capable of providing important and sustained impact on global HBV incidence, even if they have a delayed impact on sexual transmission of HBV.