Hepatitis B vaccination in HIV-infected adults: current evidence, recommendations and practical considerations

Strategies for Hepatitis B Virus Prevention in People Living with HIV

PURPOSE OF REVIEW

Coinfection with HIV and hepatitis B virus (HBV) is common owing to shared routes of transmission, and persons with HIV-HBV coinfection experience an accelerated progression of liver disease. Despite the widespread availability of HBV vaccination, rates of seroprotection in people living with HIV (PLWH) have historically been low. In this article, we review strategies in HBV prevention among PLWH, focusing specifically on updates in HBV vaccination and chemoprophylaxis.

RECENT FINDINGS

Vaccination remains the hallmark of HBV prevention, and recent studies suggest that a double dose of HBV vaccine and Heplisav-B can improve rates of seroprotection among PLWH. The use of tenofovir-containing antiretroviral therapy (ART) has similarly been shown to provide some HBV protection in PLWH; however, this protection can be lost when switching to newer tenofovir-sparing regimens, including long-acting injectables. All HBV-susceptible persons with HIV should be vaccinated against HBV, regardless of ART regimen and CD4 count.

Observational Study Evaluating the Seroprotection of HepB-alum Vaccine and HepB-CpG Vaccine in People With HIV

Background

Hepatitis B virus (HBV) vaccine seroprotection rates with conventional aluminum adjuvanted recombinant HBV vaccines, Engerix-B (HepB-alum) vaccine, among people with HIV (PWH) are varied. Heplisav-B (HepB-CpG) vaccine, a novel adjuvanted recombinant HBV vaccine, has shown higher seroprotection rates in immunocompetent patients but is not well studied in PWH. There are no published studies comparing seroprotection rates between HepB-alum and HepB-CpG in PWH. This study aims to evaluate and compare the seroprotection incidence of HepB-alum vs HepB-CpG in PWH at least 18 years of age.

Methods

This retrospective, observational cohort study included adults diagnosed with HIV who received a complete series of HepB-alum or HepB-CpG at a community health center in Phoenix, Arizona. Patients had a hepatitis B surface antibody <10 IU/L at the time of the first vaccine dose. The primary outcome was a comparison of seroconversion incidence between HepB-CpG and HepB-alum. Secondary outcomes included identifying factors associated with likelihood of response to HBV vaccination.

Results

A total of 120 patients were included in this study, 59 in the HepB-alum cohort and 61 in the HepB-CpG cohort. In the HepB-alum cohort, 57.6% achieved seroconversion, compared with 93.4% in the HepB-CpG cohort (P < .001). Those without diabetes were more likely to have response to a vaccine.

Conclusions

Among PWH at a single community health center, HepB-CpG provided a statistically higher incidence of seroprotection against HBV compared with HepB-alum.

Immunogenicity and safety of 4 intramuscular standard-dose and high-dose hepatitis B vaccine in people living with HIV: a randomized, parallel-controlled trial

OBJECTIVES

The immunogenicity of hepatitis B vaccine is unsatisfactory in the people living with HIV (PLHIV). Studies evaluating optimal regimens to enhance immunogenicity have heretofore been inconclusive. The study was to compare the immunogenicity and safety of the four standard-dose and high-dose regimens of hepatitis B vaccine among PLHIV.

METHODS

A randomized, parallel-controlled trial was conducted between May, 2020, and January, 2021. Patients were randomly assigned to receive 3 or 4 doses of 20 or 60 µg of hepatitis B vaccine. Seroconversion rate, high-level response rate, and geometric mean concentration (GMC) of antibody to hepatitis B surface antigen (anti-HBs) at weeks 12 and 28 were the main outcome measures.

RESULTS

At week 28, the seroconversion rate and GMC of anti-HBs in both IM20 × 4 and IM60 × 4 groups were significantly higher than those in the IM20 × 3 group (P < 0.05), and the GMC of anti-HBs was numerically higher in the IM60 × 4 group than that in the IM20 × 4 group.

CONCLUSIONS

In PLHIV, both the four standard-dose and high-dose regimens significantly improved immunogenicity. The GMC of anti-HBs was numerically higher in the IM60 × 4 group than that in the IM20 × 4 group.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (NCT03962803).

Microbiota-Meditated Immunity Abnormalities Facilitate Hepatitis B Virus Co-Infection in People Living With HIV: A Review

Hepatitis B virus (HBV) co-infection is fairly common in people living with HIV (PLWH) and affects millions of people worldwide. Identical transmission routes and HIV-induced immune suppression have been assumed to be the main factors contributing to this phenomenon. Moreover, convergent evidence has shown that people co-infected with HIV and HBV are more likely to have long-term serious medical problems, suffer more from liver-related diseases, and have higher mortality rates, compared to individuals infected exclusively by either HIV or HBV. However, the precise mechanisms underlying the comorbid infection of HIV and HBV have not been fully elucidated. In recent times, the human gastrointestinal microbiome is progressively being recognized as playing a pivotal role in modulating immune function, and is likely to also contribute significantly to critical processes involving systemic inflammation. Both antiretroviral therapy (ART)-naïve HIV-infected subjects and ART-treated individuals are now known to be characterized by having gut microbiomic dysbiosis, which is associated with a damaged intestinal barrier, impaired mucosal immunological functioning, increased microbial translocation, and long-term immune activation. Altered microbiota-related products in PLWH, such as lipopolysaccharide (LPS) and short-chain fatty acids (SCFA), have been associated with the development of leaky gut syndrome, favoring microbial translocation, which in turn has been associated with a chronically activated underlying host immune response and hence the facilitated pathogenesis of HBV infection. Herein, we critically review the interplay among gut microbiota, immunity, and HIV and HBV infection, thus laying down the groundwork with respect to the future development of effective strategies to efficiently restore normally diversified gut microbiota in PLWH with a dysregulated gut microbiome, and thus potentially reduce the prevalence of HBV infection in this population.

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.

Immune response to hepatitis B vaccination in human immunodeficiency virus-positive patients in China: A 2-year retrospective study

Currently, the studies focused on the immune response to hepatitis B vaccination in Chinese human immunodeficiency virus (HIV)-positive patients are limited. In this study, the participants with an initial hepatitis B surface antibody (HBsAb) titer <10 mIU/ml were assigned to Cohort 1 to receive a standard dose of recombinant hepatitis B vaccine, and participants with an initial HBsAb titer between 10 and 100 mIU/ml were assigned to Cohort 2 to receive a single reinforced recombinant vaccine. In Cohort 1, the immune and high response rates in HIV-positive patients were 93.4%/81.4%, 87.4%/51.5%, and 83.2%/40.7% at 1-3 months, 1 year, and 2 years postvaccination. Multivariate analysis showed that only age and HIV RNA status at baseline were independent factors related to sustained immune response at 2 years postvaccination. In Cohort 2, the high immune response rates in HIV-positive patients were 78.8%, 60.6%, and 51.5% at 1-3 months, 1 year, and 2 years postvaccination. The immune or high response rates did not differ between HIV-positive patients and healthy controls at 1-3 months postvaccination in these two cohorts; however, HBsAb titers were significantly lower in HIV-positive patients. This study summarized the 2-year data of immune response to hepatitis B vaccination and analyzed the factors related to sustained immune response at 2 years postvaccination in Chinese HIV-positive patients.

The potential role of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) single-tablet regimen in the expanding spectrum of fixed-dose combination therapy for HIV

Single-tablet regimens (STRs) of highly safe and effective combination antiretroviral therapy (cART) have had a significant beneficial impact on the clinical outcomes and lives of people living with HIV (PLHIV). As a consequence, healthcare professionals caring for PLHIV in high-income countries have increasingly focused on issues beyond those related to HIV itself, i.e. HIV-related neurological disease, or associated opportunistic infections, which include co-infections, and primarily age- and lifestyle-related comorbidities such as cardiovascular disease, diabetes mellitus, renal impairment, osteoporosis and frailty. This review considers drug side effects and comorbidities seen in PLHIV and evaluates the role of a recently licensed STR - bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) - in mitigating some of those challenges. Factors that need to be evaluated for initial cART regimens include: pretreatment CD4 cell count; plasma HIV RNA; HIV drug resistance; hepatitis B co-infection; HLA-B*5701 status; drug-drug interactions; pregnancy and pregnancy potential; psychiatric and physical comorbidities such as renal or bone disease, as well as simplicity and adherence-friendliness, all of which need to be considered in all lines of therapy. BIC/FTC/TAF constitutes a new STR that includes an unboosted integrase strand transfer inhibitor with a high barrier against resistance with TAF and FTC. Its virological efficacy was non-inferior to dolutegravir-based regimens previously recommended by most guidelines for treatment initiation in large double-blind, randomised clinical trials in treatment-naïve or switch patients over 96 weeks. Tolerability and pharmacological properties of the regimen make it a useful tool to address several of the clinical management issues raised above.

Immunological Considerations for Schistosoma Vaccine Development: Transitioning to Endemic Settings

Despite mass drug administration programmes with praziquantel, the prevalence of schistosomiasis remains high. A vaccine is urgently needed to control transmission of this debilitating disease. As some promising schistosomiasis vaccine candidates are moving through pre-clinical and clinical testing, we review the immunological challenges that these vaccine candidates may encounter in transitioning through the clinical trial phases in endemic settings. Prior exposure of the target population to schistosomes and other infections may impact vaccine response and efficacy and therefore requires considerable attention. Schistosomes are known for their potential to induce T-reg/IL-10 mediated immune suppression in populations which are chronically infected. Moreover, endemicity of schistosomiasis is focal whereby target and trial populations may exhibit several degrees of prior exposure as well as in utero exposure which may increase heterogeneity of vaccine responses. The age dependent distribution of exposure and development of acquired immunity, and general differences in the baseline immunological profile, adds to the complexity of selecting suitable trial populations. Similarly, prior or concurrent infections with other parasitic helminths, viral and bacterial infections, may alter immunological responses. Consequently, treatment of co-infections may benefit the immunogenicity of vaccines and may be considered despite logistical challenges. On the other hand, viral infections leave a life-long immunological imprint on the human host. Screening for serostatus may be needed to facilitate interpretation of vaccine responses. Co-delivery of schistosome vaccines with PZQ is attractive from a perspective of implementation but may complicate the immunogenicity of schistosomiasis vaccines. Several studies have reported PZQ treatment to induce both transient and long-term immuno-modulatory effects as a result of tegument destruction, worm killing and subsequent exposure of worm antigens to the host immune system. These in turn may augment or antagonize vaccine immunogenicity. Understanding the complex immunological interactions between vaccine, co-infections or prior exposure is essential in early stages of clinical development to facilitate phase 3 clinical trial design and implementation policies. Besides well-designed studies in different target populations using schistosome candidate vaccines or other vaccines as models, controlled human infections could also help identify markers of immune protection in populations with different disease and immunological backgrounds.

The role of hepatitis B vaccine challenge dose in patients with underlying health conditions

We have evaluated the immunological response to Hepatitis B virus (HBV) booster vaccine dose in 129 adults with underlying diseases in comparison with 694 subjects at occupational risk of infection, who have previously completed the primary series and resulted with anti-HBs <10 mIU/mL. After booster dose, 60.5% of the patients with underlying diseases and 14.8% of the subjects at occupational risk resulted seronegative. By comparing two groups, rate of subjects with anamnestic response was higher in at occupational risk group respect to that at risk for medical conditions (OR: 5.99 [95%IC, 3.81-9.41], p < .001). This difference was associated to gender (males/females: OR: 0.619 [95%IC, 0.421-0.910], p = .015) and age (better response for younger people, p = .011).

Evaluation of response to hepatitis B virus vaccine in adults with human immunodeficiency virus

INTRODUCTION AND AIM

Viral hepatitis is a serious public health problem. The risk of progression to chronic hepatitis in hepatitis B virus (HBV) infection occurs in 5-10% of adults and is a leading cause of cirrhosis and hepatocellular carcinoma worldwide. Individuals infected with human immunodeficiency virus (HIV) may have coinfection with HBV. The existence of unvaccinated groups represents a significant risk not only individually but also at the community level. The aim of this study was to evaluate HBV vaccine response in adults with HIV infection.

MATERIALS AND METHODS

A retrospective, descriptive study of the cross-sectional type was carried out in an outpatient HIV referral center in southern Brazil. All medical records of adult HIV patients seen during January 2006 to December 2015 were selected. In statistical analysis, a significance level of 5% was used.

RESULTS

Of the 201 patients evaluated with a complete vaccination scheme, 55.72% were males, with a mean age of 43.86±12.68 years. Vaccine response occurred in 80.10% (161/201) of the patients, and it did not correlate with age, CD4+ cell count or viral load.

CONCLUSION

HBV vaccine response in a HIV population was satisfactory, highlighting the importance of vaccination for prevention, cost reduction and better prognosis in preventing HBV/HIV coinfection.

Significance of Decreasing Rate of HIV and HBV Co-infection in a Nationwide Korean HIV/AIDS Cohort

From December 2006 to December 2016, 1093 human immunodeficiency virus (HIV) individuals < 70 years enrolled in Korea human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) cohort were analyzed to investigate the prevalence of HIV/HBV co-infection rate and hepatitis B virus surface antibody (HBsAb) positive rate based on birth year. The HBV co-infection prevalence rate was the highest (8.8%) in patients born between 1960 and 1964 and the lowest (0%) among those born between 1995 and 1999. A decreasing linear trend of HBV co-infection rate was observed according to the 5-year interval changes. HBsAb-positive rate was only 58.1% in our study. The national HBV vaccination programs have effectively lowered the HBV co-infection rate in HIV population. However, it is identified that the HIV population has low HBsAb positive rate. Further evidences supporting efficacy of booster immunization for HBsAb negative HIV patients are required and efforts should be made to increase HBsAb positive rates among HIV patients to prevent horizontal transmission.

Immunogenicity and safety of 4 vs. 3 standard doses of HBV vaccination in HIV-infected adults with isolated anti-HBc antibody

Background

Presence of isolated anti-HBc antibody is common in HIV-infected patients in endemic areas and could be caused by prior HBV infection with loss of anti-HBs antibody. The role of vaccination in these patients remains controversial and is based largely on limited and low quality data. We, therefore, conducted this study to determine immunogenicity and safety of 4 vs. 3 standard doses of HBV vaccination in HIV-infected adults with isolated anti-HBc antibody.

Methods

An open-label, randomized controlled trial was conducted among HIV-infected patients visiting HIV clinic of the Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand between July and September 2017. Inclusion criteria included ≥ 18 years of age, currently on a stable antiretroviral regimen, CD4+ cell count ≥ 200 cells/mm³, plasma HIV-1 RNA < 20 copies/mL, and isolated anti-HBc antibody. The participants were randomized to receive either 3 standard doses (20 µg at month 0, 1, 6) or 4 standard-doses (20 µg at month 0, 1, 2, 6) of IM HBV vaccination, and were evaluated for anamnestic response at week 4 and vaccine response at week 28.

Results

Of the 97 patients screened, 54 (32 male, mean age of 46 years) were enrolled and 27 were allocated to each of the vaccination groups. Anamnestic response occurred in 25.9% vs. 33.3% in 3-dose group vs. 4-dose group, respectively (p = 0.551). The vaccine response rates at week 28 were 85.2% in 3-dose group vs. 88.9% in 4-dose group (p = 1.000); geometric mean titer of anti-HBs antibody at week 28 was 63.8 and 209.8 mIU/mL in 3-dose group and 4-dose group, respectively (p = 0.030). No adverse events were reported.

Conclusions

An anamnestic response occurred in one-third of Thai HIV-infected patients with isolated anti-HBc antibody who received one dose of HBV vaccination; however, the majority were still unprotected. The use of either 3 or 4 standard-doses of vaccination was highly effective and should be recommended in all HIV-infected individuals with isolated anti-HBc antibody.

Trial registration ClinicalTrials.gov; NCT03212911. Registered 11 July 2019, https://clinicaltrials.gov/ct2/show/NCT03212911

Electronic supplementary material

The online version of this article (10.1186/s12981-019-0225-3) contains supplementary material, which is available to authorized users.

Effect of HIV-exposure and timing of anti-retroviral treatment on immunogenicity of trivalent live-attenuated polio vaccine in infants

Introduction

The prevalence of HIV infection in South African pregnant women has been approximately 30% over the past decade; however, there has been a steady decline in mother-to-child transmission of HIV from 8% in 2008 to <2% in 2015. We evaluated the immunogenicity of live-attenuated trivalent oral polio vaccine (OPV) following the primary vaccination series (doses at birth, 6, 10 and 14 weeks of age) in HIV-exposed uninfected (HEU), HIV-infected infants initiated on early anti-retroviral treatment (HIV+/ART+), HIV-infected infants on deferred ART (HIV+/ART-) and HIV-unexposed infants (HU) as the referent group.

Methods

Serum polio neutralization antibody titres were evaluated to serotype-1, serotype-2 and serotype-3 at 6, 10 and 18 weeks of age. Antibody titres ≥8 were considered seropositive and sero-protective.

Results

At 18 weeks of age, following the complete primary series of four OPV doses, no differences in GMTs, percentage of infants with sero-protective titres and median fold change in antibody titre (18 weeks vs 6 weeks) were observed in HEU infants (n = 114) and HIV+/ART+ infants (n = 162) compared to HU infants (n = 104) for the three polio serotypes. However, comparing HIV+/ART- infants (n = 70) to HU infants at 18 weeks of age, we observed significantly lower GMTs for serotype-1 (p = 0.022), serotype-2 (p<0.001) and serotype-3 (p<0.001), significantly lower percentages of infants with sero-protective titres for the three serotypes (p<0.001), and significantly lower median fold change in antibody titre for serotype-1 (p = 0.048), serotype-2 (p = 0.003) and serotype-3 (p = 0.008).

Conclusion

Delaying initiation of ART in HIV-infected infants was associated with an attenuated immune response to OPV following a four-dose primary series of vaccines, whereas immune responses to OPV in HIV-infected children initiated on ART early in infancy and HEU children were similar to HU infants.

Vaccination in the Adult Patient Infected with HIV: A Review of Vaccine Efficacy and Immunogenicity

Patients infected with HIV remain at increased risk of mortality and morbidity from diseases that are preventable with vaccines partly due to the persisting immunopathology that results in impaired responses to vaccination despite virologic suppression. Because data on clinical effectiveness in patients who are immunocompromised remain limited, undervaccination of individuals with HIV poses a major concern. Multiple societies have published recommendations on vaccination in individuals infected with HIV. Many of these recommendations are based on extrapolation of data from clinical trials that usually exclude patients with HIV, although there is a growing body of data from patients infected with HIV as well. In this review, we describe the available literature on vaccine response in the adult patient with HIV as measured by immunogenicity or vaccine efficacy.

Herpes Zoster and Herpes Zoster Vaccine Rates Among Adults Living With and Without HIV in the Veterans Aging Cohort Study

BACKGROUND

Despite historically high rates of herpes zoster among people living with HIV (PLWH), comparative studies of herpes zoster by HIV serostatus are lacking since the advent of combination antiretroviral therapy and availability of zoster vaccine.

METHODS

Annual rates (2002-2015) of first-episode herpes zoster and zoster vaccination were calculated for PLWH and uninfected adults in the Veterans Aging Cohort Study and stratified by HIV serostatus and age. Herpes zoster was captured using ICD9 codes and vaccine receipt with procedural codes and pharmacy data.

RESULTS

Of 45,177 PLWH and 103,040 uninfected veterans, rates of herpes zoster decreased among PLWH (17.6-8.1/1000) over the study period but remained higher than uninfected adults (4.1/1000) at the end of study period. Rates were higher in PLWH with lower CD4 (<200 vs >500 cells/µL: 18.0 vs 6.8/1000) and unsuppressed vs suppressed HIV-1 RNA (21.8 vs 7.1/1000). Restricted to virologically suppressed participants with CD4 >350 cells per microliter, herpes zoster rates were similar among PLWH aged younger than 60 years and aged 60 years and older in 2015 (6.6 vs 6.7/1000) but higher than all uninfected age groups. At study end, cumulative receipt of zoster vaccine for PLWH aged 60 years and older was less than half that of uninfected veterans: 98.7 vs 215.2/1000.

CONCLUSIONS

Herpes zoster rates among PLWH have markedly decreased, but, even in cART-treated individuals, remain 50% higher than uninfected adults. Lower rates of zoster vaccine receipt combined with high rates of herpes zoster support the need for a safe and effective vaccine against herpes zoster for PLWH, formal zoster vaccine guidelines for PLWH, and consideration for expanded use at younger ages.

Adverse events after vaccination among HIV-positive persons, 1990-2016

Human immunodeficiency virus (HIV) causes immune dysregulation, potentially affecting response to vaccines in infected persons. We investigated if unexpected adverse events (AEs) or unusual patterns of AEs after vaccination were reported among HIV-positive persons. We searched for domestic reports among HIV-positive persons to the Vaccine Adverse Event Reporting System (VAERS) during 1990–2016. We analyzed reports by age group (<19 and ≥19 years), sex, serious or non-serious status, live vaccine type (live versus inactivated), AEs reported, and CD4 counts. Of 532,235 reports received, 353 (0.07%) described HIV-positive persons, of whom 67% were aged ≥19 years, and 57% were male; most reports (75%) were non-serious. The most commonly reported inactivated vaccines were pneumococcal polysaccharide (27%) and inactivated influenza (27%); the mostly reported common live virus vaccines were combination measles, mumps, and rubella (8%) and varicella (6%). Injection site reactions were commonly reported (39%). Of 67 reports with CD4 counts available, 41 (61%) described persons immunocompromised at time of vaccination (CD4 count <500 cells/mm³), and differed from overall reports only in that varicella was the most common live virus vaccine (4 reports). Of 22 reports describing failure to protect against infection, 6 described persons immunocompromised at time of vaccination, among whom varicella vaccine was most common (3 reports). Of 66 reports describing live virus vaccines, 7 described persons with disseminated infection: 6 had disseminated varicella, 3 of whom had vaccine strain varicella-zoster virus. Of 18 reported deaths, 7 resulted from disseminated infection: 6 were among immunocompromised persons, 1 of whom had vaccine strain varicella-zoster virus. We identified no unexpected or unusual patterns of AEs among HIV-positive persons. These data reinforce current vaccine recommendations for this risk group. However, healthcare providers should know their HIV-positive patients’ immune status because immunocompromising conditions can potentially increase the risk of rare, but severe, AEs following vaccination with live virus vaccines.

Host genetics contributes to the effectiveness of dendritic cell-based HIV immunotherapy

Systems biological analysis has recently revealed how innate immune variants as well as gut microbiota impact the individual response to immunization. HIV-infected (HIV+) patients have a worse response rate after standard vaccinations, possibly due to the immune exhaustion, increased gut permeability and microbial translocation. In the last decade, dendritic cells (DC)-based immunotherapy has been proposed as an alternative approach to control HIV plasma viral load, however clinical trials showed a heterogeneity of immunization response. Hypothesizing that host genetics may importantly affects the outcome of immunotherapy in HIV+ patients, genetic polymorphisms' distribution and gene expression modulation were analyzed in a phase I/II clinical trial of DC-based immunotherapy according to immunization response, and quality of vaccine product (DC). Polymorphisms in genes previously associated with progression of HIV infection to AIDS (i.e.: PARD3B, CCL5) contribute to a better response to immunotherapy in HIV+ individuals, possibly through a systemic effect on host immune system, but also directly on vaccine product. Genes expression profile after immunization correlates with different degrees of immune chronic activation/exhaustion of HIV+ patients (i.e. PD1, IL7RA, EOMES), but also with anti-viral response and DC quality (i.e.: APOBEC3G, IL8, PPIA), suggested that an immunocompetent individual would have a better vaccine response. These findings showed once more that host genetics can affect the response to DC-based immunotherapy in HIV+ individuals, contributing to the heterogeneity of response observed in concluded trials; and it can be used as predictor of immunization success.

Immune response to hepatitis B vaccination in HIV-positive individuals with isolated antibodies against hepatitis B core antigen: Results of a prospective Italian study

BACKGROUND AND AIM

Antibodies against hepatitis B core antigen (anti-HBc) are found in 14-44% of patients with HIV infection, but it is still unclear whether hepatitis B virus (HBV) vaccination should be recommended for HIV-positive subjects with isolated anti-HBc (IAHBc). We examined the rate of anamnestic and primary responses (ARs and PRs) and associated factors in a group of HIV-infected patients with an IAHBc profile.

METHODS

This prospective study recruited 25 HIV-positive patients with anti-HBc alone who were vaccinated against HBV infection. Those without an AR (anti-hepatitis B envelope antigen [anti-HBs] levels of <10 U/L) or who were hypo-responsiveness (anti-HBs levels of >10 but <100 U/L) four weeks after the first dose of vaccine underwent a full course of vaccinations. Their clinical and virological data, including the presence of occult hepatitis B infection (OBI), were evaluated in accordance with the vaccination schedule.

RESULTS

Six of the 25 patients (24%) showed an AR, four of whom had anti-HBs levels of <100 U/L. Ten of 19 (52.6%) remaining patients became seroprotected after the third dose. OBI was detected in four of the six patients with an AR, two of the 10 patients with a PR, and none of the nine patients who did not respond. Multivariate analysis showed that an AR was associated with the presence of OBI (P = 0.0162), and a PR was associated with HCV antibody status. (P = 0.0191).

CONCLUSIONS

Our data suggest that testing for anti-HBc alone may not be a reliable means of assessing protection from HBV infection in HIV-positive patients. OBI-positive patients may benefit from a single vaccine dose. Anti-HCV serostatus may affect PRs.

Vaccinations for the HIV-Infected Adult: A Review of the Current Recommendations, Part I

Vaccination is a critical component for ensuring the health of those living with the human immunodeficiency virus (HIV) by protection against vaccine-preventable diseases. Since HIV-infected persons may have reduced immune responses and shorter durations of protection post-vaccination, HIV-specific guidelines have been published by global and national advisory organizations to address these potential concerns. This article provides a comprehensive review of the current guidelines and evidence-based data for vaccinating HIV-infected adults, including guidance on modified vaccine dosing and testing strategies, as well as safety considerations, to enhance protection among this vulnerable population. In the current article, part I of the two-part series, inactivated vaccines with broad indications as well as vaccines for specific risk and age groups will be discussed.

Predictors of humoral response to recommended vaccines in HIV-infected adults

Humoral response to vaccination has been found to be inadequate in individuals infected with the human immunodeficiency virus (HIV). We retrospectively assessed antibody responses to three routinely recommended vaccines, against hepatitis B, hepatitis A and S. pneumoniae, in HIV-infected individuals. Data regarding age at HIV diagnosis, years of infection, sex, nationality, HIV mode of transmission, CD4 cell count, nadir CD4 count, plasma viral load, HIV stage, insurance status, educational level and treatment with Highly Active Antiretroviral Therapy (HAART) were collected. Univariate and multivariate analysis was performed in order to detect factors associated with response to vaccination. 437 patients were assessed for hepatitis B, 627 patients for hepatitis A and 66 patients for S. pneumoniae serologic vaccine responsiveness. Regarding hepatitis B and hepatitis A, education level and insurance status were the only predictors of response. As for S. pneumoniae vaccination HAART and control of viremia were correlated with better response to vaccination.

Hepatitis B: changing epidemiology and interventions

Hepatitis B virus infection is still a major public health problem worldwide, since more than 350 million people have chronic, lifelong infection and nearly 1 million deaths occur each year owing to complications. Most infections are acquired at birth or during early childhood. Nowadays, low- and middle-income countries bear the majority of the burden of hepatitis B-related liver cancer deaths despite the availability of an effective vaccine and antiviral treatments. In this review the epidemiology, strategies of prevention and the recent advances in therapy, genotype diversity and resistance are discussed.

Hepatitis B virus vaccination in HIV-infected people: A review

HBV immunization is highly recommended in people infected with HIV. However, the classical schedule used in the general population has been shown to be insufficient in people living with HIV. This review summarizes the main studies dealing with HBV vaccination in people living with HIV, depending on their baseline status (in particular, never vaccinated, already vaccinated, or with an isolated anti-HBc serological profile). It shows that reinforced 40µg intramuscular HBV vaccination schedules are now frequently recommended, either initially in people never vaccinated, or in the lack of an anamnestic response in other situations. Adjuvants cannot be currently recommended. Anti-HBs titers have to be checked 1 to 2 months following the last vaccine dose, and annually thereafter a booster is necessary if antiHBs titers decrease below 10 mIU/mL. In patients with a CD4 cell count <200/µL, guidelines recommend starting the vaccination regimen as soon as possible after HAART has been started.

Safety and immunogenicity of RTS,S/AS01 malaria vaccine in infants and children with WHO stage 1 or 2 HIV disease: a randomised, double-blind, controlled trial

BACKGROUND

Malaria remains a major global public health concern, especially in sub-Saharan Africa. The RTS,S/AS01 malaria candidate vaccine was reviewed by the European Medicines Agency and received a positive scientific opinion; WHO subsequently recommended pilot implementation in sub-Saharan African countries. Because malaria and HIV overlap geographically, HIV-infected children should be considered for RTS,S/AS01 vaccination. We therefore aimed to assess the safety of RTS,S/AS01 in HIV-infected children at two sites in western Kenya.

METHODS

We did a randomised, double-blind, controlled trial at the clinical trial sites of the Kenya Medical Research Institute (KEMRI)-Walter Reed Army Institute of research in Kisumu and the KEMRI/US Centers for Disease Control and Prevention in Siaya. Eligible participants were infants and children aged from 6 weeks to 17 months with WHO stage 1 or 2 HIV disease (documented positive by DNA PCR), whether or not they were receiving antiretroviral therapy (ART). We randomly assigned participants (1:1) to receive three doses of either RTS,S/AS01 or rabies vaccine (both 0·5 mL per dose by intramuscular injection), given once per month at 0, 1, and 2 months. We did the treatment allocation using a web-based central randomisation system stratified by age (6 weeks-4 months, 5-17 months), and by baseline CD4% (<10, 10-14, 15-19, and ≥20). Data were obtained in an observer-blind manner, and the vaccine recipient, their parent or carer, the funder, and investigators responsible for the assessment of endpoints were all masked to treatment allocation (only staff responsible for the preparation and administration of the vaccines were aware of the assignment and these individuals played no other role in the study). We provided ART, even if the participants were not receiving ART before the study, and daily co-trimoxazole for prevention of opportunistic infections. The primary outcome was the occurrence of serious adverse events until 14 months after dose 1 of the vaccine, assessed in the intention-to-treat population. This trial was registered at ClinicalTrials.gov, number NCT01148459.

FINDINGS

Between July 30, 2010, and May 24, 2013, we enrolled 200 children to our study and randomly assigned 99 to receive RTS,S/AS01 and 101 to receive rabies vaccine. 177 (89%) of the 200 children enrolled completed 14 months of follow-up. Serious adverse events were noted in 41 (41·4%, 95% CI 31·6-51·8) of 99 RTS,S/AS01 recipients and 37 (36·6%, 27·3-46·8) of 101 rabies-vaccine recipients (relative risk 1·1, 95% CI 0·8-1·6). 20 (20·2%, 95% CI 12·8-29·5) of 99 RTS,S/AS01 recipients and 12 (11·9%, 6·3-19·8) of 101 rabies-vaccine recipients had at least one serious adverse event within 30 days after vaccination, mainly pneumonia, febrile convulsions, and salmonella sepsis. Five (5·1%, 95% CI 1·7-11·4) of 99 RTS,S/AS01 recipients and four (4·0%, 1·1-9·8) of 101 rabies-vaccine recipients died, but no deaths were deemed related to vaccination. Mortality was associated with five cases of pneumonia (1% RTS,S/AS01 recipients vs 3% rabies-vaccine recipients), five cases of gastroenteritis (3% RTS,S/AS01 recipients vs 2% rabies-vaccine recipients), five cases of malnutrition (2% RTS,S/AS01 recipients vs 3% rabies-vaccine recipients), one case of sepsis (1% rabies-vaccine recipients), one case of Haemophilus influenza meningitis (1% rabies-vaccine recipients), and one case of tuberculosis (1% RTS,S/AS01 recipients).

INTERPRETATION

RTS, S/AS01 was well tolerated when given to children with WHO clinical stage 1 or 2 HIV disease along with high antiretroviral and co-trimoxazole use. Children with HIV disease could be included in future RTS,S/AS01 vaccination programmes.

FUNDING

GlaxoSmithKline Biologicals SA and PATH Malaria Vaccine Initiative.

Infectious diseases in allogeneic haematopoietic stem cell transplantation: prevention and prophylaxis strategy guidelines 2016

Infectious complications after allogeneic haematopoietic stem cell transplantation (allo-HCT) remain a clinical challenge. This is a guideline provided by the AGIHO (Infectious Diseases Working Group) of the DGHO (German Society for Hematology and Medical Oncology). A core group of experts prepared a preliminary guideline, which was discussed, reviewed, and approved by the entire working group. The guideline provides clinical recommendations for the preventive management including prophylactic treatment of viral, bacterial, parasitic, and fungal diseases. The guideline focuses on antimicrobial agents but includes recommendations on the use of vaccinations. This is the updated version of the AGHIO guideline in the field of allogeneic haematopoietic stem cell transplantation utilizing methods according to evidence-based medicine criteria.

Hepatitis B and A vaccination in HIV-infected adults: A review

Hepatitis B and A account for considerable morbidity and mortality worldwide. Immunization is the most effective means of preventing hepatitis B and A. However, the immune response to both hepatitis vaccines seems to be reduced in HIV-infected subjects. The aim of this review was to analyze the immunogenicity, safety, long-term protection and current recommendations of hepatitis B and A vaccination among HIV-infected adults. The factors most frequently associated with a deficient level of anti-HBs or IgG anti-HAV after vaccination are those related to immunosuppression (CD4 level and HIV RNA viral load) and to the frequency of administration and/or the amount of antigenic load per dose. The duration of the response to both HBV and HAV vaccines is associated with suppression of the viral load at vaccination and, in the case of HBV vaccination, with a higher level of antibodies after vaccination. In terms of safety, there is no evidence of more, or different, adverse effects compared with HIV-free individuals. Despite literature-based advice on the administration of alternative schedules, revaccination after the failure of primary vaccination, and the need for periodic re-evaluation of antibody levels, few firm recommendations are found in the leading guidelines.

HBV and HIV co-infection: Impact on liver pathobiology and therapeutic approaches

The consequences of hepatitis B virus (HBV) and human immunodeficiency virus (HIV) co-infection on progression of severe liver diseases is a serious public health issue, worldwide. In the co-infection cases, about 90% of HIV-infected population is seropositive for HBV where approximately 5%-40% individuals are chronically infected. In HIV co-infected individuals, liver-related mortality is estimated over 17 times higher than those with HBV mono-infection. The spectrum of HIV-induced liver diseases includes hepatitis, steatohepatitis, endothelialitis, necrosis, granulomatosis, cirrhosis and carcinoma. Moreover, HIV co-infection significantly alters the natural history of hepatitis B, and therefore complicates the disease management. Though several studies have demonstrated impact of HIV proteins on hepatocyte biology, only a few data is available on interactions between HBV and HIV proteins. Thus, the clinical spectrum as well as the complexity of the co-infection offers challenging fronts to study the underlying molecular mechanisms, and to design effective therapeutic strategies.

Enhanced immune response to hepatitis B vaccination through immunization with a Pre-S1/Pre-S2/S vaccine

Efficacy and safety of recombinant yeast-derived hepatitis B vaccines for prevention of hepatitis B have been demonstrated unequivocally worldwide as reflected in reduction in HBsAg carrier rates and hepatocellular carcinoma. A new generation of recombinant HBV vaccines expressed in mammalian cells containing Pre-S/S epitopes has been developed in several countries. Such vaccines are useful in special risk groups, i.e., in non-responders to conventional HBV vaccines including older adults, obese people, health care workers, patients with renal failure and on dialysis, transplant patients, patients with HIV as well as travelers on short notice to HBV endemic regions. The future of such vaccines depends on their enhanced immunogenicity and cost profile. Sci-B-Vac™ is a mammalian cell-derived recombinant Pre-S1/Pre-S2/S hepatitis B vaccine which has been shown to be highly immunogenic, inducing faster and higher seroprotection rates against HBV with higher anti-HBs levels at lower HBsAg doses as compared to conventional yeast-derived vaccines. Recently, it has been suggested that such Pre-S/S vaccines against HBV might be efficacious not only for prevention but also for intervention in persistent HBV infection. Data obtained in a recent clinical trial conducted in Vietnam in patients with chronic hepatitis B suggest that repeated monthly i.m. injections of the Sci-B-Vac™ co-administered with daily oral lamivudine treatment can suppress HBV replication and lead to anti-HBs seroconversion in ~50 % of treated patients. Optimization of protocols and efficacy of such an intervention, intended to bypass T cell exhaustion and immune tolerance to HBV remains to be explored.

HPV in HIV-Infected Women: Implications for Primary Prevention

Background: There is growing evidence that human immunodeficiency virus (HIV)-infected women might have a different human papillomavirus (HPV) type distribution in cervical dysplasia specimens as compared to the general population. This has implications for primary prevention.

Objective: We aimed to obtain preliminary data on the HPV genotypes prevalent in histological samples of HIV-infected women with cervical intraepithelial neoplasia (CIN) 3/CIS of the cervix in Miami, FL, USA.

Methods: Retrospective data were collected on HIV-infected women referred to the University of Miami-Jackson Memorial Hospital colposcopy clinic between years 2000 and 2008. The histology slides of CIN 3/CIS biopsies underwent pathological review and sections were cut from these archived specimens for HPV DNA extraction. HPV genotyping was then performed using the GeneSquare™ HPV genotyping assay. We report on our first set of 23 samples.

Results: Eight high-risk HPV types were detected. Types in decreasing order of frequency were 16, 35, 45, 52, 59, 31, 58, and 56. Most cases had multiple infections. HPV type 16 was the most common (45%) followed by HPV-35 and -45 with equal frequency (40%). No samples contained HPV-18.

Conclusion: Our preliminary results suggest that cervical dysplasia specimens of HIV-infected women more likely (55%) contain non-16 and -18 high-risk HPV types. We show that this held true for histologically confirmed severe dysplasia and carcinoma-in situ. Epidemiological studies guide vaccine development, therefore HPV type prevalence in CIS and invasive cervical cancer among HIV-infected women should be more rigorously explored to ensure that this highly vulnerable population receives appropriate primary prevention.

Vaccination in HIV-infected adults

Vaccines are critical components for protecting HIV-infected adults from an increasing number of preventable diseases. However, missed opportunities for vaccination among HIV-infected persons persist, likely due to concerns regarding the safety and efficacy of vaccines, as well as the changing nature of vaccine guidelines. In addition, the optimal timing of vaccination among HIV-infected adults in regards to HIV stage and receipt of antiretroviral therapy remain important questions. This article provides a review of the current recommendations regarding vaccines among HIV-infected adults and a comprehensive summary of the evidence-based literature of the benefits and risks of vaccines among this vulnerable population.

Vaccination of healthcare personnel: spotlight on groups with underlying conditions

Healthcare personnel (HCP) are at increased risk of acquiring vaccine-preventable diseases (VPDs). Vaccination protects HCP and their patients from nosocomial transmission of VPDs. HCP who have underlying diseases (e.g., immunocompromised, HIV-infected, or those with chronic diseases) and HCP in particular phases of life (e.g., pregnant, elderly) require special consideration in regards the provision of vaccines. On the one hand, live virus vaccines may be contraindicated (e.g., pregnant HCP, immunocompromised HCP), while on the other hand, vaccines not routinely recommended (e.g., pneumococcal) may be indicated (e.g., elderly or immunocompromised HCP). It is not known how many HCP with underlying conditions require special consideration in the healthcare setting. This is an important issue, because the risk for serious morbidity, complications and mortality for HCP with underlying conditions will only increase. The prevention of nosocomial infections requires comprehensive occupational safety programs. The healthcare system must engage HCP and occupational physicians to ensure sufficient vaccination rates as part of an effective nosocomial infection prevention and HCP safety strategy.

Adjuvant potential of low dose all-trans retinoic acid during oral typhoid vaccination in Zambian men

There is an urgent need to identify ways of enhancing the mucosal immune response to oral vaccines. Rotavirus vaccine protection is much lower in Africa and Asia than in industrialized countries, and no oral vaccine has efficacy approaching the best systemic vaccines. All-trans retinoic acid (ATRA) up-regulates expression of α4β7 integrin and CCR9 on lymphocytes in laboratory animals, increasing their gut tropism. The aim of this study was to establish the feasibility of using ATRA as an oral adjuvant for oral typhoid vaccination. In order to establish that standard doses of oral ATRA can achieve serum concentrations greater than 10 nmol/l, we measured ATRA, 9-cis and 13-cis retinoic acid in serum of 14 male volunteers before and 3 h after 10 mg ATRA. We then evaluated the effect of 10 mg ATRA given 1 h before, and for 7 days following, oral typhoid vaccine in eight men, and in 24 men given various control interventions. We measured immunoglobulin (Ig)A directed against lipopolysaccharide (LPS)and protein preparations of vaccine antigens in whole gut lavage fluid (WGLF) and both IgA and IgG in serum, 1 day prior to vaccination and on day 14. Median [interquartile range (IQR)] C(max) was 26·2 (11·7-39·5) nmol/l, with no evidence of cumulation over 8 days. No adverse events were observed. Specific IgA responses to LPS (P = 0·02) and protein (P = 0·04) were enhanced in WGLF, but no effect was seen on IgA or IgG in serum. ATRA was well absorbed, well tolerated and may be a promising candidate oral adjuvant.

Prevalence and correlates of HIV and hepatitis B virus coinfection in Northern Alberta

BACKGROUND

HIV and hepatitis B virus (HBV) share transmission routes, and coinfection is associated with higher morbidity and mortality. To date, no Canadian studies have examined HIV-HBV coinfection.

OBJECTIVES

To examine the prevalence and correlates of HIV and HBV coinfections in Northern Alberta.

METHODS

The present study was a retrospective database review of all HIV-infected (HIV+) individuals in Northern Alberta from 1982 to 2010 and a chart review of HBV surface antigen-positive individuals for whom charts were available (46.2%).

RESULTS

Of 2844 HIV+ patients, 2579 (90.7%) had been tested for HBV surface antigen, and 143 (5.5%) of these were HBV coinfected. Coinfected males were primarily Caucasian (70.8%), and coinfected females were primarily black (56.4%) or Aboriginal (31.3%). Coinfected individuals were more likely to be male (88.1% versus 71.3%; P<0.001) and to have died (34.3% versus 17.9%; P<0.001).

CONCLUSIONS

The prevalence of coinfection with HBV in HIV-infected patients in Northern Alberta is lower than reported in other developed nations. The pattern of coinfections in Northern Alberta likely follows immigration trends. Recognition and management may be improving with time; however, further research and additional strategies are required to enhance the prevention, identification and management of HBV infection in HIV-infected individuals.

Vaccination against oncogenic human papillomavirus infection in HIV-infected populations: review of current status and future perspectives

Background Men and women with HIV infection are at increased risk of developing cancers associated with human papillomavirus (HPV). The two licensed prophylactic HPV vaccines protect against de novo infection with HPV-16 and HPV-18, which cause the majority of HPV-associated cancers. Currently, no vaccine efficacy data are available for persons with HIV infection. Nevertheless, some countries have implemented specific HPV vaccination recommendations for HIV-positive populations. To specifically recommend prophylactic HPV vaccination in people with HIV, the vaccines must be safe and immunogenic in immunosuppressed people at a high risk of HPV infection. This review aims to summarise the current knowledge from published HPV vaccine trials in HIV-infected populations, to compile scheduled and ongoing HPV vaccine trials with HIV-positive study populations and to extrapolate the relevant knowledge about HPV vaccine efficacy in HIV-negative populations to an HIV context.

METHODS

The databases PubMed, Scopus and ClinicalTrials.gov were searched for peer-reviewed articles and scheduled or ongoing clinical HPV vaccine trials enrolling HIV-positive persons.

RESULTS

Current data indicate that prophylactic HPV vaccines are safe and immunogenic in different HIV-positive populations (children, female adolescents, adults). Increased immunogenicity has been reported in persons on antiretroviral therapy compared with antiretroviral-naïve persons, whereas no clear association has been found between CD4(+) cell count at immunisation and vaccine response. Several scheduled and ongoing HPV vaccine trials aim to determine vaccine efficacy against disease endpoints in HIV-infected study populations.

CONCLUSION

Prophylactic HPV vaccination appears safe, immunogenic and, by extrapolation, likely to reduce HPV-associated cancer development among persons with HIV infection.

HBV infection in HIV-infected subjects in the state of Piauí, Northeast Brazil

In this study, the prevalence, genotype frequency, and risk factors for HBV infection in 768 HIV-infected subjects living in Piauí were determined. Forty-six (6.0 %) HIV-positive subjects were reactive for HBsAg and positive for HBV-DNA. Genotypes A (71.8 %), F (23.9 %) and D (4.3 %) were identified. Multivariate analysis revealed an association between HIV-HBV coinfection and male gender, older age groups, unprotected sex, reporting more than ten sexual partners throughout life, STD, and tattooing. This study shows the importance of monitoring sites and professionals who perform tattooing and practice safe sex to prevent the spread of HIV and HBV infections.

Factors associated with the immune response to hepatitis A vaccination in HIV-infected patients in the era of highly active antiretroviral therapy

INTRODUCTION

HIV seropositivity is considered a risk factor for complications in hepatitis A virus (HAV) infection. HAV vaccination schedules are widely implemented in HIV-infected patients, but the immune response remains impaired.

METHODS

We analysed the response to vaccination (antiHAV titres ≥20IU/l) in 282 HIV-infected patients included in a standard (1440 Elisa Units (EU) at 0, 6 months) or rapidly accelerated schedule (720 EU at 0, 7, 21 days and 6 months) between 1997 and 2009. Factors associated with the response to vaccination were analysed using logistic regression.

RESULTS

The overall response rate was 73.4%. Male sex (OR: 0.16, 95% CI 0.05-0.51) and hepatitis C virus co-infection (OR: 0.30, 95% CI 0.14-0.74) were associated with a lower probability of response. Protective antibody response was associated with a higher CD4/CD8 ratio (OR: 3.69, 95% CI 1.3-10.5) and having received two doses of standard schedule (compared with patients receiving only one dose of the same schedule) (OR: 2.51, 95% CI 1.22-5.15). Three doses of the rapidly accelerated schedule were not more effective than a single dose of 1440 EU (OR: 1.32, 95% CI 0.48-3.63).

CONCLUSION

The low responses observed in patients receiving a single dose suggest the need to emphasize adhesion to vaccination protocols to avoid failure. The CD4/CD8 ratio may be considered as an immune status marker which could help to better choose the moment of vaccination. Our findings underscore the importance of identifying strategies that optimize the timing and effectiveness of hepatitis A vaccination in HIV-infected patients and of the need for further studies on individual factors such as sex and hepatitis C co-infection that may affect the response to vaccination. Likewise, the sub-optimal effectiveness of three doses of 720 EU in the rapidly accelerated schedule, if confirmed in future studies, might lead to a revision of the current schedule recommended for HIV-infected travellers.

Does increased hepatitis B vaccination dose lead to a better immune response in HIV-infected patients than standard dose vaccination: a meta-analysis?

Human immunodeficiency virus (HIV)-infected patients often fail to produce protective antibodies to hepatitis B virus (HBV) vaccine. Some reports have suggested that increased-dose vaccination improves immune response to HBV vaccine in HIV-infected patients. To assess the efficacy of increased-dose HBV vaccination in HIV-infected patients, a systematic review of the literature and meta-analysis of clinical trials was conducted. We only included trials that compared the response rate at completion of HBV vaccine schedules in patients who had increased-dose HBV vaccine courses with controls (standard-dose HBV vaccine vaccination schedule). The fixed-effects model, with heterogeneity and sensitivity analyses, was used in this study. We identified five studies involving 883 HIV-positive vaccine recipients. Pooling of study results showed a significant increase in response rates among high-dose patients versus control patients; the pooled odds ratio (OR) was 1.96 (95% confidence interval [CI]: 1.47; 2.61). Four out of five identified studies included only vaccine-naive patients. The overall OR was 1.82 (95% CI: 1.35–2.47). No study heterogeneity was found. Our meta-analysis showed that increasing the dosage of vaccine may significantly improve immune responses in HIV-infected patients.

Hepatitis B virus prevalence and vaccine response in HIV-infected children and adolescents on combination antiretroviral therapy in Kigali, Rwanda

OBJECTIVE

The aim of this study was to determine the prevalence of hepatitis B virus (HBV) infection in a cohort of HIV-infected Rwandan children and adolescents on combination antiretroviral therapy (cART), and the success rate of HBV vaccination in those children found to be HBV negative.

METHODS

HIV-infected children and adolescents (age 8-17 years) receiving cART with CD4 T-cells count ≥200 cells/mm and/or ≥15% and without prior HBV vaccination (by history, vaccination cards and clinic records) underwent serologic testing for past (negative HBV surface antigen [HBsAg] with positive antibody to HBV core antigen [cAb] and to HBsAg [anti-HBs]) or active HBV infection (positive HBsAg). Children with any positive HBV serologic tests were excluded from further vaccination; all others completed 3 HBV immunizations with 10 µg of ENGERIX-B. Anti-HBs titer was measured 4-6 weeks after the last immunization.

RESULTS

Of 88 children, 6 (7%) children had active HBV infection and 8 (9%) had past HBV infection. The median (interquartile range) age, CD4 T-cell count and cART duration were 12.3 (10.1-13.9) years, 626 (503 to 942) cells/mm and 1.9 (1.5-2.7) years, respectively. Seventeen children had detectable plasma HIV-1 RNA. Seventy-3 children completed 3 immunizations with median (interquartile range) postimmunization anti-HBs concentration of 151 mIU/mL (1.03-650). Overall, 52 children (71%, 95% confidence interval: 61-82) developed a protective anti-HBs response. HIV-1 RNA and CD4 T-cell count were independent predictors of a protective anti-HBs response. Protective anti-HBs response was achieved in 82% of children with undetectable HIV-1 RNA and 77% with CD4 T cells ≥350/mm.

CONCLUSIONS

The substantial HBV prevalence in this cohort suggests that HIV-infected Rwandan children should be screened for HBV before cART initiation. HIV viral suppression and CD4 T cells ≥350/mm favored the likelihood of a protective response after HBV vaccination.

Immunization of HIV infected children

Immunization is one of the most effective approaches to reduce morbidity and mortality in HIV infected children. However, progressive immune suppression may lead to impaired responsiveness to most of the vaccines. Besides this, there are many other areas of concern in these children including risk of diseases and safety issues with live vaccines, need for increased amount or number of doses of a particular vaccine, shortened duration of protective efficacy, need for revaccination after immune reconstitution and effect of vaccines on HIV viral replication. Published literature on safety, effectiveness and immunogenicity of vaccines in HIV infected children and status of individual vaccines with existing guidelines has been discussed in present review.

Immune response to hepatitis B virus vaccination among HIV-1 infected and uninfected adults in Kenya

BACKGROUND

In studies from high-income countries, human immunodeficiency virus type 1 (HIV-1)-infected persons have diminished responses to hepatitis B virus (HBV) vaccination, compared with HIV-1-uninfected persons, but data from other settings are limited.

METHODS

We compared the immune response to HBV vaccination among HIV-1-infected and HIV-1-uninfected Kenyan adults and assessed the response of HIV-1-infected initial nonresponders to revaccination with a standard HBV vaccine series.

RESULTS

Of 603 participants, 310 (51.4%) were HIV-1-infected, for whom the median CD4(+) T-cell count was 557 cells/μL (interquartile range, 428-725 cells/μL); none were receiving antiretroviral therapy. Nonresponse to HBV vaccine was higher among HIV-1-infected participants, compared with HIV-1-uninfected participants (35.8% vs 14.3%; odds ratio, 3.33; P < .001). Of 102 HIV-1-infected initial nonresponders, 88 (86.3%) responded to revaccination, for an overall response, including to revaccination, of 94.9%. Among HIV-1-infected individuals, lower CD4(+) T-cell counts and male sex were independent predictors of nonresponse to initial vaccination, and lower body mass index, higher plasma HIV-1 RNA levels, and longer time to revaccination predicted nonresponse to revaccination.

CONCLUSIONS

Kenyan adults had similar HBV vaccination responses as persons from high-income countries. Timely revaccination of HIV-1-infected nonresponders increased response to the vaccine to 95%.

Challenges for HCV vaccine development in HIV-HCV coinfection

It is estimated that 4-5 million HIV-infected patients are coinfected with HCV. The impact of HIV on the natural course of HCV infection is deleterious. This includes a higher rate of HCV persistence and a faster rate of fibrosis progression. Coinfected patients show poor treatment outcome following standard HCV therapy. Although direct antiviral agents offer new therapeutic options, their use is hindered by potential drug interactions and toxicity in HIV-infected patients under HAART. Overtime, a large reservoir of HCV genotype 1 patients will accumulate in resource poor countries where the hepatitis C treatment is not easily affordable and HIV therapy remains the primary health issue for coinfected individuals. HCV vaccines represent a promising strategy as an adjunct or alternative to current HCV therapy. Here, the authors review the pathogenesis of hepatitis C in HIV-infected patients, with a focus on the impact of HIV on HCV-specific immune responses and discuss the challenges for vaccine development in HIV-HCV coinfection.

Impact of a nurse vaccination program on hepatitis B immunity in a Swiss HIV clinic

We evaluated the impact of a nurse program for hepatitis B virus vaccination in a center from the Swiss HIV Cohort Study. Immunity (anti-HBs >10 IU/mL) increased from 32% to 76% in the intervention center (n = 238) where vaccine management was endorsed by nurses, but only from 33% to 39% in control centers (n = 2712, P < 0.001) where management remained in charge of physicians. Immunity against HBV in the HIV population is insufficient in Switzerland. Specific nurse vaccination program may efficiently improve health care.

Vaccination against hepatitis B in an HIV outpatients' department: an audit against national vaccination guidelines

Practice related to hepatitis B vaccination of HIV outpatients in a London teaching hospital was audited against the British HIV Association (BHIVA) immunization guidelines 2004 and 2008, both before and after the implementation of a vaccination record sheet in the patients' notes. Adherence to the guidelines in the original audit was poor - only 67% of patients requiring vaccination for hepatitis B received a full course of vaccination. Following the introduction of the vaccination record sheet, this vaccination completion rate increased to 79% (BHIVA target 95%). Overall the percentage of patients managed according to BHIVA guidelines, including those who did not require vaccination, improved from 33% in the original audit to 61% in the re-audit. Introduction of a simple hepatitis B vaccination record sheet improved the quality of care for our HIV outpatients. Further modification of this system is warranted, perhaps by the introduction of a computerized reminder system.

Human papillomavirus, cancer and vaccination

PURPOSE OF REVIEW

HIV-positive men and women are at greater risk of human papillomavirus (HPV)-related cancers compared with the general population. This study describes recent findings in HPV-related cancers and precancerous lesions and discuss the potential benefit of recently developed prophylactic HPV vaccines.

RECENT FINDINGS

Despite improving access to antiretroviral therapy (ART), particularly in developing countries, the incidence of cervical cancer has not declined and the incidence of anal cancer is still rising in HIV-infected individuals. HIV appears to affect the history of HPV infection, and the distribution of genotypes detected in precancerous lesions in HIV-infected women is not similar to that of the general population. The use of the quadrivalent HPV vaccine has been shown to prevent cervical precursor lesions caused by the vaccine types in women in the general population. Safety and immunogenicity studies of the quadrivalent HPV vaccine in HIV-infected individuals are underway. Efficacy has to be proven in the context of both a different epidemiology of HPV infection and of immunosuppression.

SUMMARY

Recent data imply that the issue of HPV-related cancers will not decline in HIV-infected individuals. Therefore, efficacy studies of HPV vaccines are sorely needed in the setting of HIV.

Immunization in the adult immunocompromised host

The number of patients with impaired immune response has been steadily increasing within the last years, not only with the onset of the AIDS epidemic, but also due to increasing numbers of subjects on immunosuppressive therapies. These patients are at an increased risk for infections, many of which are preventable by immunization. Inactivated vaccines are generally safe in subjects with underlying immunosuppression. However, immune response and protection may be hampered, depending on the extent of immunosuppression. In contrast, live vaccines such as yellow fever, measles, rubella, herpes zoster, and cholera may lead to severe reactions in immunocompromised patients and have been shown to deteriorate some immune-mediated diseases such as multiple sclerosis. Data on the efficacy of vaccines in biological therapies is scarce. Where necessary vaccines should be updated before immunosuppressive therapies are started. To improve the vaccination status several guidelines exist for immunosuppressed patients at risk such as those with rheumatic diseases, asplenia or solid organ and hematopoietic stem cell transplantation.