Vaccination against hepatitis B virus among people who inject drugs - A 20year experience from a Swedish needle exchange program

Hepatitis B virus infection and vaccination among people who use drugs in Xi'an, China

BACKGROUND

While hepatitis B virus (HBV) infection in children has declined dramatically in China due to the vaccination strategy for newborns, HBV infection in high-risk adults is receiving an increasing attention. The number of people who use drugs (PWUD) in China is huge, but their status of HBV infection and vaccination is less reported, especially from large samples. The related knowledge can help decision makers develop the further strategy of HBV prevention and control.

METHODS

A seroepidemiological survey was conducted in all four compulsory isolated detoxification centers (CIDCs) and all eight methadone maintenance treatment (MMT) clinics located in Xi'an, China. All PWUD who were undergoing detoxification or treatment in these settings were included. A questionnaire was designed to obtain the information of HBV vaccination history of participants, and sociodemographic and behavioral data of participants were obtained from the registration records of their respective CIDCs or MMT clinics.

RESULTS

A total of 4705 PWUD participated in the survey. Positive rates of HBsAg (current infection) and HBsAg or anti-HBc (current/past infection) were 5.50% and 58.02%, notably higher than those reported for the general adult population in the same province during the same period. As age increased, the anti-HBc positive rate increased with statistically significant trend. The all-negative for HBsAg, anti-HBc, and anti-HBs accounted for 28.82%. Only 18.49% were identified by the questionnaire as having received HBV vaccine. The logistic regression found that compared with identified vaccinated PWUD, those unsure if having been vaccinated and those identified non-vaccinated had a significantly higher HBV current/past infection rate, with an increasing trend.

CONCLUSION

PWUD are a high-risk adult group of HBV infection in China. Of them, more than half have not received HBV vaccine, and a significant portion are susceptible to HBV. Catch-up vaccination is need for this population to prevent and control HBV transmission.

COVID-19 vaccine implementation at a syringe services program: experiences of frontline staff

BACKGROUND

While people with substance use disorders, including people who inject drugs (PWID), experience increased risk for COVID-19 infection and adverse outcomes, COVID-19 vaccination rates among PWID are consistently lower than those observed in the general population. Offering COVID-19 vaccines at syringe services programs (SSPs) has been proposed as a critical strategy to increase vaccine uptake among this population. We explored the experiences of frontline staff at an SSP in Miami, Florida implementing onsite COVID-19 vaccines.

METHODS

Between June and July 2022, we conducted in-depth semi-structured interviews with 17 staff members of an SSP in Miami, Florida. Data collection and codebook thematic analysis of transcribed interviews were guided by the Consolidated Framework for Implementation Research (CFIR).

RESULTS

Facilitators and barriers of COVID-19 vaccine implementation at the SSP aligned with all major CFIR domains. Key facilitators included the SSP's established partnership with the local health department for vaccine distribution, its existing funding sources which could be leveraged for vaccine-related expenses, consensus among staff about the need for new strategies to increase vaccine uptake among PWID, and PWID's trust in the SSP. Major-but largely modifiable-barriers included lack of participant compensation, limited internal collaboration and communication regarding the vaccine initiative beyond implementation leads and innovation deliverers due to competing priorities and segmented roles and responsibilities, and insufficient involvement of the most participant-facing staff (i.e., the SSP's peer navigators and outreach workers).

CONCLUSIONS

Implementing onsite COVID-19 vaccines was perceived as feasible and acceptable by frontline staff at the SSP, however contextual factors impeded optimal implementation. Multilevel strategies, such as participant compensation for vaccine completion and internal educational meetings with staff to improve vaccine implementation and reach, are required. As a trusted source of preventative services for PWID, SSPs are an underutilized venue for increasing vaccine uptake among this population, and findings from this study could inform the expansion of low-barrier vaccine services at SSPs nationwide.

The Effectiveness and Sero-Immunity of Hepatitis B Vaccination in People Who Use Drugs: A Systematic Review and Meta-Analysis

Hepatitis B virus (HBV) vaccination has been available for over four decades. However, a synthesis of the evidence regarding the effectiveness of this strategy on preventing hepatitis B infection in people who use drugs (PWUD) is lacking. A systematic search of the MEDLINE (via PubMed), SCOPUS, Web of Science, and Cochrane Library databases was conducted up to June 2024. Eight studies reported on the effectiveness of HBV vaccination, defined as a positive result for HBsAg or anti-Hbc in vaccinated versus non-vaccinated PWUD, with a pooled effect size of 52% (95% CI: 28.2-67.9) for HBsAg and 31.89% (95% CI: 14.8-45.5) for anti-Hbc. For sero-immunity, defined as the proportion of vaccinated PWUD with levels of anti-HBs ≥ 10 mIU/mL, we found that 66.2% (95% CI: 0.61-0.71; I2 = 94%) had protective levels of anti-HBs. The results of this meta-analysis indicate that the incidence of HBV infection is lower in vaccinated PWUD than in those who did not receive the vaccine. However, the effectiveness is lower than that observed in the general population. This highlights the need for a thorough review of the factors influencing the prevention of HBV infection in PWUD.

Characterising the effectiveness of social determinants of health-focused hepatitis B interventions: a systematic review

Social determinants of health are important in designing effective interventions for hepatitis B virus (HBV) infection. This systematic review characterises equity-oriented, social determinants of health-focused HBV interventions, and describes their effectiveness in terms of the prevention, care, or treatment of HBV in high-income countries. We searched electronic databases for central concepts of 'HBV', 'equity', 'social determinants of health', 'intervention', and 'Organization for Economic Co-operation and Development (OECD) countries'. Screening and data abstraction were conducted independently by two reviewers. Data were abstracted from 66 studies; articles with a comparative study design (n=36) were included in the narrative synthesis, highlighting social determinants of health domains of interventions, HBV-relevant health outcomes, and extra-health social determinants of health effects (ie, those effects that extend beyond health outcomes). Synthesis aligned with six emergent themes corresponding to HBV prevention and care: knowledge and education, diagnosis and screening, immunisation, care initiation, engagement with clinical care and treatment, and upstream prevention. Studies presented a heterogeneous array of HBV-relevant health outcomes. Most interventions were tailored for social determinants of health domains of race, ethnicity, culture, and language; drug use; and socioeconomic status. Across the themes, at least two-thirds of interventions showed comparative effectiveness for addressing HBV. Extra-health social determinants of health outcomes were observed for two studies. Considerable diversity in population-level approaches was observed regarding intervention goals and effectiveness; most interventions were effective at enhancing the prevention, care, or treatment of HBV.

Comparison of hepatitis B and SARS-CoV2 vaccination rates in people who attended Drugs and Addiction Centres

Background and aims

Persons with substance use disorder are at increased risk for hepatitis B virus (HBV) infection. Although most of them are attached to social health centers, the vaccination rate in this group is low. In this context, we designed a study to evaluate the prevalence of users of drug addiction centers (DAC) not immunized against hepatitis B and to compare the rate of vaccination against hepatitis B with the rate of immunization against SARS-Cov-2 in 2 years of follow-up.

Design

Retrospective study that included individuals attended at DAC. Patients were screened at baseline (June 2020-January 2021) for HBV immunization. Individuals with HBsAb < 10 IU/mL were recommended to receive hepatitis B vaccine, during follow-up (January 2021-October 2022). At the end of follow-up, the HBV vaccination rate among candidates was determined and compared with the vaccination rate against SARS-Cov-2 in this population in the same period.

Findings

A total of 325 subjects were surveyed and tested. At baseline, the 65% (211/325) of were candidates to initiate vaccination and were advisor to HBV vaccination. During the follow-up 15 individuals received at least one dose of HBV vaccine, supposing a vaccination rate of 7.2%. In the same period, 186 individuals received at least one dose against SARS-Cov-2, representing a vaccination rate of 83%. The comparison between vaccination rates reached statistically significant (p < 0.001).

Conclusion

Our study manifests a low rate of immunization against HBV in DAC users, despite a high level of immunization for SARS-Cov-2 during the same period in the same population. Consequently, the lack of immunization against HVB in this population might be related with health policy issue more than to individuals linked to care and awareness. A similar approach for vaccination intended for SARS-CoV2 should be applied in high-risk population to warrant the success of immunization program against other preventable diseases such as HBV.

High Primary COVID-19 Vaccine Series Completion by People Who Inject Drugs When Colocating Services at a Syringe Services Van

OBJECTIVE

The aim of the study is to describe the impact of colocating COVID-19 vaccinations with local syringe service programs on vaccine completion among people who inject drugs.

METHODS

Data were derived from 6 community-based clinics. People who inject drugs who received at least one COVID-19 vaccine from a colocated clinic partnering with a local syringe service program were included in the study. Vaccine completion was abstracted from electronic medical records; additional vaccinations were abstracted using health information exchanges embedded within the electronic medical records.

RESULTS

Overall, 142 individuals with a mean age of 51 years, predominantly male (72%) and Black, non-Hispanic (79%) received COVID-19 vaccines. More than half elected to receive a 2-dose mRNA vaccine (51.4%). Eighty-five percent completed a primary series, and 71% of those who received a mRNA vaccine completed the 2-dose series. Booster uptake was 34% in those completing a primary series.

CONCLUSIONS

Colocated clinics are an effective means of reaching vulnerable populations. As the COVID-19 pandemic continues and need for annual booster vaccines arises, it is important to bolster public support and funding to continue low-barrier preventive clinics colocated with harm reduction services for this population.

COVID-19 vaccine attitudes and facilitators among people in Australia who inject drugs

INTRODUCTION

We aimed to describe COVID-19 vaccination attitudes and identify potential facilitators for vaccine uptake among people who inject drugs.

METHODS

People who inject drugs were recruited from all eight Australian capital cities (N = 884; 65% male, mean age 44 years) and interviewed face-to-face or via telephone in June-July 2021. COVID-19 and broader vaccination attitudes were used to model latent classes. Correlates of class membership were assessed through multinomial logistic regression. Probability of endorsing potential vaccination facilitators were reported by class.

RESULTS

Three classes of participants were identified: 'vaccine acceptant' (39%), 'vaccine hesitant' (34%) and 'vaccine resistant' (27%). Those in the hesitant and resistant groups were younger, more likely to be unstably housed and less likely to have received the current season influenza vaccine than the acceptant group. In addition, hesitant participants were less likely to report a chronic medical condition than acceptant participants. Compared to vaccine acceptant and hesitant participants, vaccine-resistant participants were more likely to predominantly inject methamphetamine and to inject drugs more frequently in the past month. Both vaccine-hesitant and resistant participants endorsed financial incentives for vaccination and hesitant participants also endorsed facilitators related to vaccine trust.

DISCUSSION AND CONCLUSION

People who inject drugs who are unstably housed or predominantly inject methamphetamine are subgroups that require targeted interventions to increase COVID-19 vaccination uptake. Vaccine-hesitant people may benefit from interventions that build trust in vaccine safety and utility. Financial incentives may improve vaccine uptake among both hesitant and resistant people.

Supporting syringe services programs in the initiation and scale-up of vaccine administration: findings from in-depth interviews

Background

Vaccine-hesitant persons who inject drugs are at increased risk for several vaccine-preventable diseases. However, vaccination rates among this population remain low. While syringe services programs (SSPs) are places where persons who inject drugs feel comfortable accessing services, few offer vaccination services. This study describes facilitators and barriers to vaccination at SSPs.

Methods

We used convenience sampling to conduct semi-structured, qualitative in-depth interviews with 21 SSPs in the USA from June to August 2021. Interview questions asked SSPs about their perceptions, priorities, barriers, facilitators, and the effects of partnerships and policies on vaccine administration. We used deductive thematic analysis to identify the main themes.

Results

Eight (n = 8) SSPs offered vaccinations, and thirteen (n = 13) did not offer vaccinations. Most SSPs believed offering vaccination services was important, although addressing SSP participants’ immediate needs often took precedence. Staffing, physical space, and logistical issues were the most common barriers to vaccine administration reported by SSPs, followed by SSP participant-related barriers. Facilitators of vaccine administration included access to a tracking system, partnering with agencies or other organizations providing vaccines, and having a licensed vaccination provider on-site. Partnerships provided SSPs opportunities to expand capacity but could also restrict how SSPs operate. Recommended policy changes to facilitate vaccine administration included subsidizing the cost of vaccinations and addressing restrictions around who could administer vaccinations.

Conclusions

Increasing the availability of vaccination services at SSPs requires addressing the varying capacity needs of SSPs, such as tracking systems, licensed vaccinators, and free or low-cost vaccination supplies. While these needs can be met through partnerships and supportive policies, both must consider and reflect cultural competence around the lived experiences of persons who inject drugs.

Dealing with low access to harm reduction: a qualitative study of the strategies and risk environments of people who use drugs in a small Swedish city

BACKGROUND

The development of harm reduction has been limited in many areas of Sweden. This study aims to understand the implications that this has for the life circumstances and risk management of people who use drugs in areas of low access.

METHODS

Eleven qualitative, semi-structured interviews were undertaken with people who use drugs in a small urban centre with no needle and syringe exchange program (NSP) or Housing First policy.

RESULTS

Participants reported many solutions to lack of NSP, including travel to an external NSP, creating bridging distribution networks, stealing, borrowing, reusing, ordering online, and smuggling injection equipment. They were at risk of having their equipment confiscated by police. Participants were mostly homeless, and to address exclusion from housing services, were forced to frequently find new temporary solutions, sheltering themselves in public places, with friends, in cars, among others. Participants felt the lack of services reflected stigmatized notions of drug use and heightened their exclusion from general society. For example, they avoided accessing other health care services for fear of discrimination. These issues caused high levels of stress and anxiety, in addition to serious risk for many somatic and psychological health conditions, including HIV and HCV transmission.

CONCLUSION

Lack of harm reduction services placed a great burden on study participants to develop strategies due to gaps in official programming. It also contributes to a vicious cycle of exclusion from services. The implementation of such evidence-based programs will reduce this burden, as well as provide the indirect, symbolic effect of inclusion.

Risk Factors and Prevention of Viral Hepatitis-Related Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a common cancer in the world, and its incidence is increasing yearly. Hepatitis B virus (HBV) infection and hepatitis C virus (HCV) infection are important causes of HCC. Liver cirrhosis, age, sex, smoking and drinking, and metabolic risk factors will increase the risk of cancer in HBV/HCV patients. And viral load, APRI, FIB-4, and liver stiffness can all predict the risk of HCC in patients with viral infection. In addition, effective prevention strategies are essential in reducing the risk of HCC. The prevention of HCC involves mainly tertiary prevention strategies, while the primary prevention is based on standardized vaccine injections to prevent the occurrence of HBV/HCV. Eliminating the route of transmission and vaccination will lead to a decrease in the incidence of HCC. Secondary prevention involves effective antiviral treatment of HBV/HCV to prevent the disease from progressing to HCC, and tertiary prevention is actively treating HCC to prevent its recurrence.

Effects of hepatitis B vaccine boosters in different levels of epidemic areas on anti-HBs-negative children after primary vaccination

Introduction. The widespread of hepatitis B virus is a severe global public problem, and the infant hepatitis B vaccine has been proved effective. But the failure of the immune response was reported in studies, and boosters were recommended. There were few studies about the effect of hepatitis B vaccine boosters in different levels of the epidemic area.Hypothesis. Booster immunization is recommended because there may be a lack of immunization in infants vaccinated with the hepatitis B vaccine. In order to verify the effectiveness of booster immunization, this study hypothesized that it worked well in different levels of endemic areas.Aim. To evaluate the effects of hepatitis B vaccine boosters on children from the areas with different prevalence of hepatitis B whose hepatitis B surface antibody (anti-HBs) were negative (<10 mIU ml^-1).Methodology. A total of 940 children were initially enrolled in screening; however, 421 were excluded. The participants were divided into three groups according to the different areas they come from: group I, low epidemic area; group II, middle epidemic area; and group III, high epidemic area. In total, 519 subjects were administered three doses of booster hepatitis B vaccine (0-1-6 months, 10 µg). The antibody titre changes were examined at four time points: 1 month after dose 1, 1 month, 1 year and 5 years after dose 3.Results. The protective seroconversion rates in three groups were 96.30, 97.16, 96.63% at 1 month after dose 1, and 100.00, 100.00, 100.00% at 1 month after dose 3, and 97.79, 100.00, 98.50% at 1 year after dose 3, and 90.77, 93.67, 93.59% at 5 years after dose 3 (P>0.05).Conclusions. This study demonstrates that three doses of booster vaccination have a longtime effect, no matter whether it is in low, middle or high prevalence areas in which subjects live.

Gaps in Hepatitis B Vaccination Completion and Sero-Protection for People Who Inject Drugs in Hpakant, Myanmar, 2015-2018

Hepatitis B vaccination (HBV) is recommended for high-risk groups, such as people who inject drugs (PWIDs). As part of a harm reduction program by a non-governmental organization, hepatitis B screening, vaccination and antibody (HBAb) testing after completion of the vaccination schedule were offered to PWIDS in Myanmar. We determined the proportions of HBV non-completion and sero-unprotection among PWIDs enrolled in the program and their association with socio-demographic and clinical characteristics. We conducted a descriptive study based on routine program data in five selected clinics in Hpakant Township, Myanmar. PWIDs who were Hepatitis B antigen negative at screening during January 2015–December 2018 were included. Among 5386 participants eligible for HBV, 9% refused vaccination. Among those who accepted vaccination (n = 3177 individuals), 65% completed vaccination. Of those tested for HBsAb (n = 2202), 30% were sero-unprotected. Young-adults (aged 18–44 years) and migrant workers had a higher risk of incomplete vaccination. However, participants who used methadone had a lower risk of incomplete vaccination. Migrant workers had higher risk of not returning for HBsAb testing and HIV-positive participants had a higher risk of being HBV sero-unprotected. Efforts to increase HBV vaccination in PWIDs for young adults and clients during methadone and anti-retroviral services should be prioritized.

Incident hepatitis B virus infection and immunisation uptake in Australian prison inmates

INTRODUCTION

Despite an effective vaccine, hepatitis B virus (HBV) infection continues to impose a large burden of disease globally. Until childhood immunisation achieves high adult population coverage, people who inject drugs (PWID), including prison inmates remain at risk. PWID have a higher prevalence of HBV than the wider population, and lower rates of vaccine-conferred immunity. This study sought to identify the incidence and predictors of HBV transmission and uptake of immunisation in PWID prisoners in Australia.

METHODS

Longitudinally collected, stored sera from subjects previously enrolled in a prospective study of hepatitis C in recently incarcerated PWID prisoners (n = 590) were serologically tested for HBV. Interviews recording demographic and behavioural risks were analysed. Multivariate statistical analyses were applied to identify associations of incident infection or immunisation.

RESULTS

Upon imprisonment there were n = 373 (63%) individuals who were HBV susceptible, of whom 140 remained susceptible at the subsequent enrolment into the cohort, and had one or more follow-up visits (a total of 406.73 person years [p.y.]), and so were included in this analysis. There were 7 incident cases of HBV infection (1.7 per 100 p.y.) in this group, with transmission being associated with injecting drug use daily or more often. There were 48 individuals who were successfully immunised (11.8 per 100 p.y.) with younger age and continuous imprisonment predicting this outcome.

CONCLUSIONS

The Australian prison environment poses a high risk for HBV infection, and also provides an opportunity for immunisation for PWID. Further efforts are required to improve coverage and prevent ongoing transmissions.

Cost-effectiveness of Hepatitis B Virus Infection Screening and Treatment or Vaccination in 6 High-risk Populations in the United States

Background

Two million individuals with chronic hepatitis B (CHB) in the United States are at risk for premature death due to liver cancer and cirrhosis. CHB can be prevented by vaccination and controlled with treatment.

Methods

We created a lifetime Markov model to estimate the cost-effectiveness of strategies to prevent or treat CHB in 6 high-risk populations: foreign-born Asian/Pacific Islanders (API), Africa-born blacks (AbB), incarcerated, refugees, persons who inject drugs (PWID), and men who have sex with men (MSM). We studied 3 strategies: (a) screen for HBV infection and treat infected ("treatment only"), (b) screen for HBV susceptibility and vaccinate susceptible ("vaccination only"), and (c) screen for both and follow-up appropriately ("inclusive"). Outcomes were expressed in incremental cost-effectiveness ratios (ICERs), clinical outcomes, and new infections.

Results

Vaccination-only and treatment-only strategies had ICERs of $6000-$21 000 per quality-adjusted life-year (QALY) gained, respectively. The inclusive strategy added minimal cost with substantial clinical benefit, with the following costs per QALY gained vs no intervention: incarcerated $3203, PWID $8514, MSM $10 954, AbB $17 089, refugees $17 432, and API $18 009. Clinical complications dropped in the short/intermediate (1%-25%) and long (0.4%-16%) term. Findings were sensitive to age, discount rate, health state utility in immune or susceptible stages, progression rate to cirrhosis or inactive disease, and tenofovir cost. The probability of an inclusive program costing <$50 000 per QALY gained varied between 61% and 97% by population.

Conclusions

An inclusive strategy to screen and treat or vaccinate is cost-effective in reducing the burden of hepatitis B virus among all 6 high-risk, high-prevalence populations.

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.