An accelerated hepatitis B vaccination schedule for young drug users

Vaccination coverage among people who inject drugs: A systematic review

BACKGROUND

People who inject drugs may be at excess risk of acquiring vaccine-preventable diseases and negative associated health outcomes, but experience barriers to vaccination. We aimed to determine vaccination coverage among people who inject drugs globally.

METHODOLOGY

We conducted systematic searches of the peer-reviewed and grey literature, date limited from January 2008 to August 2023, focusing on diseases for which people who inject drugs are at elevated risk for and for which an adult vaccination dose is recommended (COVID-19, hepatitis A, hepatitis B, human papillomavirus, influenza, pneumococcal disease, tetanus). To summarise available data, we conducted a narrative synthesis.

RESULTS

We included 78 studies/reports comprising 117 estimates of vaccination coverage across 36 countries. Most estimates were obtained from high income countries (80%, n=94). We located estimates for hepatitis B vaccination in 33 countries, which included 18 countries with data on serological evidence of vaccine-derived hepatitis B immunity (range: 6-53%) and 22 countries with self-report data for vaccine uptake (<1-96%). Data for other vaccines were scarcer: reported hepatitis A vaccination coverage ranged 3-89% (five countries), COVID-19 ranged 4-84% (five countries), while we located estimates from fewer than five countries for influenza, tetanus, pneumococcal disease, and human papillomavirus.

CONCLUSION

Estimates were sparse but where available indicative of suboptimal vaccination coverage among people who inject drugs. Improving the consistency, timeliness, and geographic coverage of vaccine uptake data among this population is essential to inform efforts to increase uptake.

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.

Hepatitis B: changes in epidemiological features of Afro-descendant communities in Central Brazil

Hepatitis B virus (HBV) infection is still a concern in vulnerable populations. In a study performed by our team in 1999–2003 in two Afro-Brazilian communities, Furnas dos Dionísios (FD) and São Benedito (SB), high prevalence rates of HBV exposure (42.7% and 16.0%, respectively), high susceptibility to HBV (55.3% and 63.0%) and low HBV vaccination like profile rates (2.0% and 21.0%) were observed. In 2015–2016, we reassessed HBV epidemiological and molecular features in these two communities to verify the impact of health actions adopted in the last years. The prevalence rate of HBV exposure among the enrolled 331 subjects was 35.3% in FD and 21.8% in SB. HBV chronic infection (5.8% in FD, 4.9% in SB) remained high. The rate of HBV vaccination like profile increased from 10.7% to 43.5% (2.0% to 45.9% in FD, 21.0% to 39.5% in SB) while susceptible subjects declined from 58.9% to 26.3% (55.3% to 18.8% in FD, 63.0% to 38.7% in SB). Among 18 HBsAg positive samples, 13 were successfully sequenced (pre-S/S region). Phylogenetic analyses showed that all isolates belong to HBV subgenotype A1, clustering within the Asian-American clade. Despite the maintenance of high prevalence rate of HBV exposure over these 13 years of surveillance, significant improvements were observed, reinforcing the importance of facilitated HBV vaccination to difficult-to-access population to close gaps in prevention.

Low prevalence, low immunization and low adherence to full hepatitis B vaccine scheme and high-risk behaviors among crack cocaine users in central Brazil

Crack cocaine users represent a target group for hepatitis B vaccination. We evaluate the HBV epidemiology, immunization status and compliance with a super-accelerated vaccination schedule among in-treatment crack cocaine users in central Brazil. Six hundred in-treatment crack cocaine users were interviewed, and serum samples were tested for HBV markers. A super-accelerated vaccination schedule of HBV vaccine was offered to all susceptible crack cocaine users. In total, 7.0% of those tested had at least one positive marker of HBV exposure. Age, use of crack cocaine through improvised pipe, exchange of sex for money/drugs and previous sexually transmitted infections (STIs) were predictors of HBV exposure. One hundred six (17.7%) individuals showed a serological profile of hepatitis B vaccination. Of these, 54.7% were less than 25 years old, and only 13% of individuals were more than 35 years old. Although 91.8% of crack users accepted the first vaccine dose, only 21.7% received all three doses. Of the 23 crack cocaine users who agreed to have their vaccine response evaluated, 78.3% developed protective anti-HBs titers. Premature termination of treatment was the most common reason for not receiving the full vaccine series. Despite the low prevalence of HBV exposure among in-treatment crack cocaine users in central Brazil, the low rate of immunization and the high frequency of high-risk behaviors highlight the potential for crack users to acquire and disseminate this infection and therefore maintain the viral reservoir. Health practitioners need to keep this in mind, taking advantage of all opportunities to access this population and vaccinate against HBV.

Getting the shots: methods to gain adherence to a multi-dose vaccination program for inner city, drug-involved prostitution communities

Street-based sex-work and poly-substance drug use, coupled with low vaccination rates and limited utilization of the mainstream health care system, put the sex worker communities of Bogotá's city center at extreme risk of infection with the hepatitis B virus (HBV). Vaccination is critical to maintaining low prevalence of the disease and low incidence of new cases, yet the floating and inconsistent nature of Bogotá's drug-involved female and transsexual prostitution communities make it difficult to complete a 3-dose vaccination program. Between December 2011 and March of 2012, the Fénix Foundation collaborated with the Bogotá Health Department to deliver free HBV vaccines to this vulnerable population. This paper outlines methods used in the vaccination program to generate a 37.7% adherence rate, significantly higher than that previously reported for HBV vaccination programs also targeting marginalized populations. This program's practices are based on the Fénix peer leader method, and are offered as a model that can be applied to other health interventions operating in analogous contexts, with similarly high-risk populations.

Factors associated with hepatitis B vaccine series completion in a randomized trial for injection drug users reached through syringe exchange programs in three US cities

Background

Hepatitis B virus (HBV) is a vaccine preventable infection yet vaccination rates are low among injection drug users (IDUs) despite the high risk of infection and longstanding recommendations to promote vaccination. We sought to improve vaccination rates by reaching IDUs through syringe exchange programs (SEPs) in three U.S. cities.

Methods

IDUs were randomized in a trial comparing the standard HBV vaccination schedule (0, 1, and 6 months) to an accelerated schedule (0, 1, and 2 months) and participation data were analyzed to identify determinants of completion of the three-dose vaccine series. Independent variables explored included sociodemographics, injection and syringe access behaviors, assessment of health beliefs, HBV-associated knowledge, and personal health status.

Results

Covariates associated with completion of the three-dose vaccine series were accelerated vaccine schedule (aOR 1.92, 95% CI 1.34, 2.58, p = <0.001), older age (aOR 1.05, 95% CI 1.03, 1.07, p = <0.001), and poorer self-rated health score (aOR 1.26, 95% CI 1.05, 1.5, p = 0.02). Completion was less likely for those getting syringes from SEP customers than for SEP customers (OR 0.33, 95% CI 0.19, 0.58, p = <0.001).

Conclusions

SEPs should offer hepatitis vaccination in a manner that minimizes time between first and last visits by accelerating the dosing schedule. Public health interventions should target younger, less healthy, and non-SEP customer participants. Other health interventions at SEPs may benefit from similar approaches that reach out beyond regular SEP customers.

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.

Interventions for young people in Australia to reduce HIV and sexually transmissible infections: a systematic review

Background: Like young people in other developed countries, sexually active young Australians can have an increased risk of acquiring sexually transmissible infections (STIs). This paper reviews intervention programs that aim to reduce the incidence and transmission of HIV and STIs among young people in Australia. Methods: Articles were identified from seven databases. Intervention studies conducted in Australia that included young people aged 12–25 years were reviewed. A two-dimensional matrix consisting of ‘setting’ and ‘intervention type’ was developed to categorise each study. Results: Forty-two studies met the inclusion criteria, and the majority were uncontrolled intervention studies. Of these, 23/42 studies measured participation in chlamydia ± other STI testing and found that the highest participation rates took place in non-clinical and non-general practice health care settings. Four studies facilitated access to testing indirectly, through the internet or other media. Ten studies involved the provision of education and measured its impact on factors such as knowledge, attitudes and/or behaviour. Three studies involved novel immunisation strategies for either hepatitis B or human papillomavirus vaccines. Two studies evaluated the impact of enhanced STI surveillance programs on prevalence rates. Conclusions: Proactive STI testing in non-clinical and some health settings appears feasible and achieves higher testing rates than in general practice; however, more evaluation of testing strategies in general practice settings is required. New technologies such as the internet and SMS are useful adjuncts for influencing behaviours such as condom use and STI testing. Media campaigns that promote STI testing can have a positive impact on testing 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.

Drug users' participation in a free hepatitis B vaccination program: demographic, behavioral, and social-cognitive determinants

The present study was conducted as an evaluation of a two-year pilot program started in 1998 in the Netherlands to provide free hepatitis B vaccination targeted at drug users (DUs). In order to identify which demographic and social-cognitive factors predict vaccination uptake, written questionnaires were distributed in three pilot regions (Amsterdam, Tiel, and Maastricht) amongst all DUs that were invited to participate in the program during a 2-month period. Vaccination behavior 2 years later was anonymously and prospectively linked to the questionnaire data, which allowed us to investigate which factors predict vaccination behavior. Of the 207 DUs eligible for vaccination (i.e., who were not immune and/or had no current infection with the virus), 93 DUs had obtained vaccination in the 2 years following the questionnaire. More than half of them (N = 50) had completed the full program (3 injections). As possible predictors of vaccination uptake, the questionnaire included constructs of the Theory of Planned Behavior as well as of the Health Belief Model. Our results show that attitude toward obtaining hepatitis B vaccination was positively associated with intention toward obtaining hepatitis B vaccination. However, perceived behavioral control was found to be the only construct related to actual vaccination uptake. None of the demographic variables were related to vaccination uptake. Our findings suggest that future interventions aimed at increasing uptake of vaccination against hepatitis B in DUs should address DUs (perceived) control concerning this behavior. The study's limitations are noted.

Acute hepatitis B 14 years after the implementation of universal vaccination in Italy: areas of improvement and emerging challenges

BACKGROUND

Italy had intermediate-level endemicity for hepatitis B virus (HBV) infection in the 1970s and 1980s. In 1991, vaccination of infants and adolescents became mandatory. We report the impact of universal vaccination 14 years after its beginning.

METHODS

We performed a case-control study within a population-based surveillance for acute viral hepatitis. The incidence of acute hepatitis B (AHB) was estimated for the time since 1991, and the association between AHB and the considered risk factors was analyzed for the period 2001-2005.

RESULTS

The incidence of AHB progressively decreased from 1991 to 2005, mainly for persons in the age groups targeted by the universal vaccination campaign: there was a 24-fold and 50-fold decrease in the 15-24-year and 0-14-year age groups, respectively; for the > or =25-year age group, the incidence halved. Owing to the persons' ages, approximately 3% of total AHB cases should have been the target of vaccination campaign. In 2004-2005, foreigners accounted for 14% of total cases and for 57% of persons who should have been targets for vaccination. Missed opportunities for immunization were documented for approximately 50% of patients with AHB who reported cohabitation with HBV carriers and for 70% of those who reported injection drug use. The strongest associations with AHB were found for blood transfusion (adjusted odds ratio [OR(adj)], 8.4; 95% confidence interval [CI], 2.7-26), cohabitation with HBV carriers (OR(adj), 5.3; 95% CI, 3.6-7.7), injection drug use (OR(adj), 3.8; 95% CI, 2.5-5.8), and unsafe sexual practices (OR(adj), 2.8; 95% CI, 1.9-4.2).

CONCLUSION

Universal vaccination has contributed to a decreasing AHB incidence in Italy, especially by reducing the risk of infection among persons aged 15-24 years. Most infections occur in persons aged > or =25 years in association with injection drug use, unsafe sexual activity, percutaneous treatment, and iatrogenic exposure. Improvement of vaccine coverage in high-risk groups and adherence to infection control measures during surgery and percutaneous treatment are needed. The high risk still associated with blood transfusion needs to be further investigated, with consideration of occult HBV infection in blood donors. The potential spread of HBV infection from the immigrant population deserves adequate health policy prevention programs.

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

INTRODUCTION

Vaccination is an important tool in hepatitis B prevention. However, several vaccine doses are required to induce long-term protection. Several at-risk groups have difficulties in adhering to the standard vaccination schedule.

OBJECTIVES

This paper aims to review the use of accelerated hepatitis B vaccination schedules, in terms of immunogenicity and compliance.

RESULTS

Accelerated schedules (0.1.2.12 months) or super-accelerated schedules (0.7.21.360 days) have been shown to result in higher proportions of healthy vaccinees reaching anti-HBs antibody levels >or=10 IU/l more rapidly. A fourth completing dose is required to lift antibody levels to an equal height, as does a standard (0.1.6 months) schedule. Accelerated schedules do also increase the uptake of hepatitis B vaccine, that is the proportion of vaccinees who receive three doses. However, completing the schedule with a fourth dose is usually more difficult than completing a standard 0.1.6-month schedule. Several additional tools can help to increase the compliance (eg, reminder systems, outreach services and incentive schemes).

CONCLUSION

For rapid seroconversion and almost immediate protection in the short term, a (super)accelerated schedule could be used in at-risk groups. As long-term protection data with these (super) accelerated schedules have not been documented yet, a fourth dose at month 12 is still required. A shortened schedule (0.1.4 months) might be an alternative worth considering compared with the standard 0.1.6, as it convenes to internationally accepted minimum dose intervals and offers earlier protection. There is a clear need to study the long-term protection and effectiveness of the primary part of (super)accelerated schedules.

Liver disease in adolescents: A cohort study of high-risk individuals

Little is known about the health and behavior of adolescent offenders as they relate to abnormalities of liver biochemistry and hepatitis C virus (HCV) infection. A large study of male juvenile offenders was undertaken that allowed a re-evaluation of the normal limits of alanine aminotransferase (ALT), associations with elevated ALT, and HCV antibody positivity. Young offenders (age 12-19 years) serving community orders participated in a wide-ranging health survey and laboratory assessment between October 2003 and December 2005. Normal ranges for liver biochemistry were calculated from the 95th percentile of males at the lowest risk for liver disease. The final sample comprised 682 males, of whom 439 (64%) gave blood. The calculated upper limit of normal for ALT was 28 IU/L. Seventeen percent of adolescents had an elevated ALT. Strong associations with elevated ALT included HCV antibody positivity [odds ratio (OR) 14.6], overweight and obesity (OR 6.9), and elevated total cholesterol (OR 3.6). More than 90% of adolescents with elevated ALT levels had 1 or more features of the metabolic syndrome. HCV antibody was positive in approximately 3% of the cohort, with the most significant risk factor being injecting drug use (OR 7.8; P < 0.01). The new infection rate was 3.7% per year.

CONCLUSION

New upper limits for ALT provide greater sensitivity for the early diagnosis of liver disease in adolescents. High rates of HCV infection and obesity-related liver disease exist in this group, and targeted interventions are needed to reduce future health-related morbidity.

Convenience is the key to hepatitis A and B vaccination uptake among young adult injection drug users

BACKGROUND

Despite CDC recommendations to vaccinate injection drug users (IDUs) against hepatitis A virus (HAV) and hepatitis B virus (HBV) infections, coverage remains low. Vaccination programs convenient to IDUs have not been widely implemented or evaluated. We assessed whether convenience and monetary incentives influenced uptake of free vaccine by 18-30-year-old IDUs in five U.S. cities.

METHODS

IDUs recruited from community settings completed risk behavior self-interviews and testing for antibodies to HAV (anti-HAV) and hepatitis B core antigen (anti-HBc). Vaccine was offered presumptively at pre-test (except in Chicago); on-site availability and incentives for vaccination differed by site, creating a quasi-experimental design.

RESULTS

Of 3181 participants, anti-HAV and anti-HBc seroprevalence was 19% and 23%, respectively. Although 83% of participants were willing to be vaccinated, only 36% received > or =1 dose, which varied by site: Baltimore (83%), Seattle (33%), Los Angeles (18%), New York (17%), and Chicago (2%). Participation was highest when vaccine was available immediately on-site and lowest when offered only after receiving results. Monetary incentives may have increased participation when on-site vaccination was not available.

CONCLUSION

IDUs were willing to be vaccinated but immediate, on-site availability was critical for uptake. Convenience should be a key consideration in designing strategies to increase vaccine coverage among IDUs.

Predictors of completion of a hepatitis B vaccination schedule in attendees at a primary health care centre

BACKGROUND

In Australia, rates of hepatitis B (HBV) transmission continue to be higher in certain populations, including commercial sex workers and injecting drug users (IDU). This study aims to identify rates and predictors of completion of a HBV vaccination schedule in 'high-risk' attendees of a primary health care centre in Sydney.

METHODS

All clients who attended Kirketon Road Centre, a primary health care centre located in Kings Cross, Sydney, with no evidence of HBV immunity were included in the cohort. The study design was observational with historical controls. The main outcome measure was completion of a three-dose HBV vaccine schedule in the study period.

RESULTS

Among 2085 clients who received a first vaccination, 1013 (49%) received a second and 435 (21%) received a third vaccination. Univariate analysis found that significant predictors of completion of the vaccine schedule were intention to administer an accelerated schedule (OR 1.49, P = 0.004), not being an IDU (OR 1.29, P = 0.02) and shorter time between first visit and first vaccine dose (OR 1.24, P for trend <0.0001); however, on multivariate analysis, not being an IDU was no longer a predictor of vaccine completion.

CONCLUSION

Implementation of an accelerated vaccination schedule improved completion rates but they were still low, despite the provision of free vaccination in a service specifically targeting the needs of sex workers, IDU and other marginalised populations. Increasing HBV vaccine uptake and completion rates in Australian adults is an important public health issue not only for the prevention of HBV but also for the future application of other potential vaccines, including those against HIV and hepatitis C.

Twinrix®vaccination schedules among injecting drug users

Twinrix is the only licensed vaccine that provides dual protection against infection with hepatitis A virus (HAV) and hepatitis B virus (HBV). The standard vaccination schedule for Twinrix is 0, 1 and 6 months. However, many high-risk populations, such as injecting drug users (IDUs), do not complete the vaccination series and, thus, do not acquire sufficient immunity against HAV and HBV. Twinrix can be administered using an accelerated vaccination schedule of 0, 7 and 21 days, with a booster recommended at 12 months. This manuscript reviews the available literature on vaccinating IDUs against HAV and HBV. The authors conclude that there is insufficient evidence regarding whether the accelerated Twinrix HAV/HBV vaccination schedule would yield a greater number of IDUs protected against both HAV and HBV.