Are adolescents ready for tuberculosis vaccine trials?

Tuberculosis Immunoreactivity Surveillance in Malawi (Timasamala)-A protocol for a cross-sectional Mycobacterium tuberculosis immunoreactivity survey in Blantyre, Malawi

Tuberculosis (TB) transmission and prevalence are dynamic over time, and heterogeneous within populations. Public health programmes therefore require up-to-date, accurate epidemiological data to appropriately allocate resources, target interventions, and track progress towards End TB goals. Current methods of TB surveillance often rely on case notifications, which are biased by access to healthcare, and TB disease prevalence surveys, which are highly resource-intensive, requiring many tens of thousands of people to be tested to identify high-risk groups or capture trends. Surveys of "latent TB infection", or immunoreactivity to Mycobacterium tuberculosis (Mtb), using tests such as interferon-gamma release assays (IGRAs) could provide a way to identify TB transmission hotspots, supplementing information from disease notifications, and with greater spatial and temporal resolution than is possible to achieve in disease prevalence surveys. This cross-sectional survey will investigate the prevalence of Mtb immunoreactivity amongst young children, adolescents and adults in Blantyre, Malawi, a high HIV-prevalence city in southern Africa. Through this study we will estimate the annual risk of TB infection (ARTI) in Blantyre and explore individual- and area-level risk factors for infection, as well as investigating geospatial heterogeneity of Mtb infection (and its determinants), and comparing these to the distribution of TB disease case-notifications. We will also evaluate novel diagnostics for Mtb infection (QIAreach QFT) and sampling methodologies (convenience sampling in healthcare settings and community sampling based on satellite imagery), which may increase the feasibility of measuring Mtb infection at large scale. The overall aim is to provide high-resolution epidemiological data and provide new insights into methodologies which may be used by TB programmes globally.

Factors related to willingness to participate in biomedical research on neglected tropical diseases: A systematic review

BACKGROUND

Understanding the barriers to and facilitators of participation in research could enhance recruitment rates for biomedical research on Neglected Tropical Diseases (NTDs) and help to avoid the problems associated with poor recruitment.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a systematic review to identify factors related to willingness to participate in biomedical research on Neglected Tropical Diseases (NTDs). Our search included the following databases: Medline/PubMed, Embase (Embase.com), Global Index Medicus (WHO), Web of Science (Core collection), and gray literature. We included studies that analyzed or reported factors associated with willingness to participate in NTD research, using either quantitative methods (such as clinical trials, cohorts, and cross-sectional studies) or qualitative methods (such as focus group discussions, semi-structured interviews, and in-depth interviews). There were no language restrictions, but we excluded review articles, notes, case reports, letters to the editor, editor's notes, extended abstracts, proceedings, patents, editorials, and other editorial materials. Screening of citations, data extraction, and risk of bias assessment was conducted by independent reviewers, according to the study protocol registered on PROSPERO. For analyses, we assessed the frequency of barriers, enablers, and the frequency of recruitment interventions mentioned in the included studies. The protocol for this systematic review was registered under registration number CRD42020212536. (S1 Appendix) We identified 2070 citations, 1470 from the databases, and 600 from other sources. From those, eleven studies were selected for data extraction and analysis. The studies were conducted in Africa, Asia, and North America. Personal health benefits, monetary benefits, and community engagement and sensitization strategies were identified as the main reasons for participating in biomedical research on Neglected Tropical Diseases (NTDs). However, distrust in researchers, lack of knowledge about research methods among potential participants, and previous negative experiences were identified as the main barriers to participating in biomedical research on NTDs.

CONCLUSIONS/SIGNIFICANCE

This systematic review provides recommendations for improving adherence to biomedical research on Neglected Tropical Diseases, which can be applied in practice.

Know your tuberculosis epidemic-Is it time to add Mycobacterium tuberculosis immunoreactivity back into global surveillance?

Tuberculosis (TB) still causes 1.5 million deaths globally each year. Over recent decades, slow and uneven declines in TB incidence have resulted in a falling prevalence of TB disease, which increasingly concentrates in vulnerable populations. Falling prevalence, while welcome, poses new challenges for TB surveillance. Cross-sectional disease surveys require very large sample sizes to accurately estimate disease burden, and even more participants to detect trends over time or identify high-risk areas or populations, making them prohibitively resource-intensive. In the past, tuberculin skin surveys measuring Mycobacterium tuberculosis (Mtb) immunoreactivity were widely used to monitor TB epidemiology in high-incidence settings, but were limited by challenges with both delivering and interpreting the test. Here we argue that the shifting epidemiology of tuberculosis, and the development of new tests for Mtb infection, make it timely and important to revisit the strategy of TB surveillance based on infection or immunoreactivity. Mtb infection surveys carry their own operational challenges and fundamental questions, for example: around survey design and frequency; which groups should be included; how the prevalence of immunoreactivity in a population should be used to estimate force of infection; how individual results should be interpreted and managed; and how surveillance can be delivered efficiently and ethically. However, if these knowledge gaps are addressed, the relative feasibility and lower costs of Mtb infection surveillance offer a powerful and affordable opportunity to better "know your TB epidemic", understand trends, identify high-risk and underserved communities, and tailor public health responses to dynamic epidemiology.

Improving vaccination uptake among adolescents

BACKGROUND

Adolescent vaccination has received increased attention since the Global Vaccine Action Plan's call to extend the benefits of immunisation more equitably beyond childhood. In recent years, many programmes have been launched to increase the uptake of different vaccines in adolescent populations; however, vaccination coverage among adolescents remains suboptimal. Therefore, understanding and evaluating the various interventions that can be used to improve adolescent vaccination is crucial.

OBJECTIVES

To evaluate the effects of interventions to improve vaccine uptake among adolescents.

SEARCH METHODS

In October 2018, we searched the following databases: CENTRAL, MEDLINE Ovid, Embase Ovid, and eight other databases. In addition, we searched two clinical trials platforms, electronic databases of grey literature, and reference lists of relevant articles. For related systematic reviews, we searched four databases. Furthermore, in May 2019, we performed a citation search of five other websites.

SELECTION CRITERIA

Randomised trials, non-randomised trials, controlled before-after studies, and interrupted time series studies of adolescents (girls or boys aged 10 to 19 years) eligible for World Health Organization-recommended vaccines and their parents or healthcare providers.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened records, reviewed full-text articles to identify potentially eligible studies, extracted data, and assessed risk of bias, resolving discrepancies by consensus. For each included study, we calculated risk ratios (RR) or mean differences (MD) with 95% confidence intervals (CI) where appropriate. We pooled study results using random-effects meta-analyses and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 16 studies (eight individually randomised trials, four cluster randomised trials, three non-randomised trials, and one controlled before-after study). Twelve studies were conducted in the USA, while there was one study each from: Australia, Sweden, Tanzania, and the UK. Ten studies had unclear or high risk of bias. We categorised interventions as recipient-oriented, provider-oriented, or health systems-oriented. The interventions targeted adolescent boys or girls or both (seven studies), parents (four studies), and providers (two studies). Five studies had mixed participants that included adolescents and parents, adolescents and healthcare providers, and parents and healthcare providers. The outcomes included uptake of human papillomavirus (HPV) (11 studies); hepatitis B (three studies); and tetanus-diphtheria-acellular-pertussis (Tdap), meningococcal, HPV, and influenza (three studies) vaccines among adolescents. Health education improves HPV vaccine uptake compared to usual practice (RR 1.43, 95% CI 1.16 to 1.76; I² = 0%; 3 studies, 1054 participants; high-certainty evidence). In addition, one large study provided evidence that a complex multi-component health education intervention probably results in little to no difference in hepatitis B vaccine uptake compared to simplified information leaflets on the vaccine (RR 0.98, 95% CI 0.97 to 0.99; 17,411 participants; moderate-certainty evidence). Financial incentives may improve HPV vaccine uptake compared to usual practice (RR 1.45, 95% CI 1.05 to 1.99; 1 study, 500 participants; low-certainty evidence). However, we are uncertain whether combining health education and financial incentives has an effect on hepatitis B vaccine uptake, compared to usual practice (RR 1.38, 95% CI 0.96 to 2.00; 1 study, 104 participants; very low certainty evidence). Mandatory vaccination probably leads to a large increase in hepatitis B vaccine uptake compared to usual practice (RR 3.92, 95% CI 3.65 to 4.20; 1 study, 6462 participants; moderate-certainty evidence). Provider prompts probably make little or no difference compared to usual practice, on completion of Tdap (OR 1.28, 95% CI 0.59 to 2.80; 2 studies, 3296 participants), meningococcal (OR 1.09, 95% CI 0.67 to 1.79; 2 studies, 3219 participants), HPV (OR 0.99, 95% CI 0.55 to 1.81; 2 studies, 859 participants), and influenza (OR 0.91, 95% CI 0.61 to 1.34; 2 studies, 1439 participants) vaccination schedules (moderate-certainty evidence). Provider education with performance feedback may increase the proportion of adolescents who are offered and accept HPV vaccination by clinicians, compared to usual practice. Compared to adolescents visiting non-participating clinicians (in the usual practice group), the adolescents visiting clinicians in the intervention group were more likely to receive the first dose of HPV during preventive visits (5.7 percentage points increase) and during acute visits (0.7 percentage points for the first and 5.6 percentage points for the second doses of HPV) (227 clinicians and more than 200,000 children; low-certainty evidence). A class-based school vaccination strategy probably leads to slightly higher HPV vaccine uptake than an age-based school vaccination strategy (RR 1.09, 95% CI 1.06 to 1.13; 1 study, 5537 participants; moderate-certainty evidence). A multi-component provider intervention (including an education session, repeated contacts, individualised feedback, and incentives) probably improves uptake of HPV vaccine compared to usual practice (moderate-certainty evidence). A multi-component intervention targeting providers and parents involving social marketing and health education may improve HPV vaccine uptake compared to usual practice (RR 1.41, 95% CI 1.25 to 1.59; 1 study, 25,869 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

Various strategies have been evaluated to improve adolescent vaccination including health education, financial incentives, mandatory vaccination, and class-based school vaccine delivery. However, most of the evidence is of low to moderate certainty. This implies that while this research provides some indication of the likely effect of these interventions, the likelihood that the effects will be substantially different is high. Therefore, additional research is needed to further enhance adolescent immunisation strategies, especially in low- and middle-income countries where there are limited adolescent vaccination programmes. In addition, it is critical to understand the factors that influence hesitancy, acceptance, and demand for adolescent vaccination in different settings. This is the topic of an ongoing Cochrane qualitative evidence synthesis, which may help to explain why and how some interventions were more effective than others in increasing adolescent HPV vaccination coverage.

The willingness to participate in biomedical research involving human beings in low- and middle-income countries: a systematic review

Objectives

To systematically review reasons for the willingness to participate in biomedical human subjects research in low‐ and middle‐income countries (LMICs).

Methods

Five databases were systematically searched for articles published between 2000 and 2017 containing the domain of ‘human subjects research’ in ‘LMICs’ and determinant ‘reasons for (non)participation’. Reasons mentioned were extracted, ranked and results narratively described.

Results

Ninety‐four articles were included, 44 qualitative and 50 mixed‐methods studies. Altruism, personal health benefits, access to health care, monetary benefit, knowledge, social support and trust were the most important reasons for participation. Primary reasons for non‐participation were safety concerns, inconvenience, stigmatisation, lack of social support, confidentiality concerns, physical pain, efficacy concerns and distrust. Stigmatisation was a major concern in relation to HIV research. Reasons were similar across different regions, gender, non‐patient or patient participants and real or hypothetical study designs.

Conclusions

Addressing factors that affect (non‐)participation in the planning process and during the conduct of research may enhance voluntary consent to participation and reduce barriers for potential participants.

Lessons from the first clinical trial of a non-licensed vaccine among Ugandan adolescents: a phase II field trial of the tuberculosis candidate vaccine, MVA85A

Background: A more effective vaccine for tuberculosis (TB) is a global public health priority. Vaccines under development will always need evaluation in endemic settings, most of which have limited resources. Adolescents are an important target population for a new TB vaccine and for other vaccines which are relevant at school-age. However, in most endemic settings there is limited experience of trials of investigational products among adolescents, and adolescents are not routinely vaccinated. Methods: We used Modified vaccinia Ankara-expressing Ag85A (MVA85A), a well-tolerated candidate vaccine for tuberculosis, to assess the effect of Schistosoma mansoni infection on vaccine immunogenicity among Ugandan adolescents in primary school. We describe here the challenges and lessons learned in designing and implementing this first clinical trial among Ugandan adolescents using a non-licensed vaccine. Results: The school based immunization study was feasible and adhered to Good Clinical Practice principles.  Engagement with the community and all stakeholders was critical for successful implementation of the trial. Creative and adaptable strategies were used to address protocol-specific, operational and logistical challenges. This study provided lessons and solutions that can be applied to other trials among adolescents in similar settings elsewhere, and to school-based immunization programs. Conclusion: Sufficient time and resources should be planned for community preparation and sensitization to ensure buy in and acceptance of a project of this kind. This trial shows that challenges to implementing early field trials in Africa are not insurmountable and that necessary well-planned high-quality ethical trials are feasible and should be encouraged. Trial Registration: ClinicalTrials.gov NCT02178748 03/06/2014.

Knowledge, attitudes and practices on adolescent vaccination among adolescents, parents and teachers in Africa: A systematic review

INTRODUCTION

Vaccines are the most successful and cost-effective public health interventions available to avert vaccine-preventable diseases and deaths. Despite global progress in adolescent health, many adolescents in Africa still get sick and die from vaccine-preventable diseases due to lack of vaccination. Adolescents, parents and teachers are key players in the development and implementation of adolescent vaccination policies. Optimal knowledge, attitudes and practices towards adolescent vaccination among these key players may improve vaccine uptake among adolescents. We conducted a qualitative and quantitative systematic review on knowledge, attitudes and practices of adolescent vaccination among adolescents, parents and teachers in Africa.

METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, WHOLIS, Africa Wide and CINAHL for eligible quantitative and qualitative primary studies with no time limits. We also checked reference lists of included studies for eligible studies and searched grey literature. Two authors independently screened the search outputs, selected studies and extracted data; resolving discrepancies by consensus and discussion. Qualitative data were analysed using thematic analyses where applicable, while analyses from quantitative studies used different methods based on the type of outcomes.

RESULTS

We included 18 cross-sectional studies in this review. The included studies were conducted in 10 out of the 54 countries in Africa. The 18 studies focused on a wide range of adolescent vaccines. Thirteen studies evaluated vaccines against Human Papilloma Virus, while each of the remaining 5 studies, evaluated vaccines against rabies, HIV, tetanus toxoid, tuberculosis and adolescent vaccines in general. Among the key players, we found low to moderate levels of knowledge about adolescent vaccination. Positive attitudes and practices towards adolescent vaccination, especially against Human Papilloma Virus were reported. Despite the low knowledge, our results showed high levels of acceptability to adolescent vaccination among adolescents, parents and teachers.

CONCLUSIONS

It was evident in our review that all key demographics (parents, adolescents and teachers) were receptive towards adolescent vaccines. We propose relevant policy makers in Africa to consider continuous education programs such as those aimed to inform the parents, adolescents and teachers on adolescent vaccination.

Motivations and concerns about adolescent tuberculosis vaccine trial participation in rural Uganda: a qualitative study

Introduction

Research is being carried out to develop and test new potentially more effective tuberculosis vaccines. Among the vaccines being developed are those that target adolescents. This study explored the stakeholders’ perceptions about adolescent participation in a hypothetical tuberculosis vaccine trial in Ugandan adolescents.

Methods

Focus group discussions with adolescents, parents of infants and adolescents, and key informant interviews with community leaders and traditional healers were conducted.

Results

The majority of the respondents expressed potential willingness to allow their children participate in a tuberculosis vaccine trial. Main motivations for potential participation would be being able to learn about health-related issues. Hesitations included the notion that trial participation would distract the youths from their studies, fear of possible side effects of an investigational product, and potential for being sexually exploited by researchers. In addition, bad experiences from participation in previous research and doubts about the importance of research were mentioned. Suggested ways to motivate participation included: improved clarity on study purpose, risks, benefits and better scheduling of study procedures to minimize disruption to participants’ academic schedules.

Conclusion

Findings from this study suggest that the community is open to potential participation of adolescents in a tuberculosis vaccine trial. However, there is a need to communicate more effectively with the community about the purpose of the trial and its effects, including safety data, in a low-literacy, readily understood format. This raises a challenge to researchers, who cannot know all the potential effects of a trial product before it is tested.

Stakeholder Views of Clinical Trials in Low- and Middle-Income Countries: A Systematic Review

CONTEXT

Clinical trials are necessary to improve the health care of children, but only one-quarter are conducted in the low- to middle-income countries (LMICs) in which 98% of the global burden of disease resides.

OBJECTIVE

To describe stakeholder beliefs and experiences of conducting trials in children in LMICs.

DATA SOURCES

Electronic databases were searched to August 2014.

STUDY SELECTION

Qualitative studies of stakeholder perspectives on conducting clinical trials among children in LMICs.

DATA EXTRACTION

Findingswere analyzed by using thematic synthesis.

RESULTS

Thirty-nine studies involving 3110 participants (children [n = 290], parents or caregivers [n = 1609], community representatives [n = 621], clinical or research team members [n = 376], regulators [n = 18], or sponsors [n = 15]) across 22 countries were included. Five themes were identified: centrality of community engagement (mobilizing community, representatives' pivotal role, managing expectations, and retaining involvement); cognizance of vulnerability and poverty (therapeutic opportunity and medical mistrust); contending with power differentials (exploitation, stigmatization, and disempowerment); translating research to local context (cultural beliefs, impoverishment constraints, and ethical pluralism); and advocating fair distribution of benefits (health care, sponsor obligation, and collateral community benefits).

LIMITATIONS

Studies not published in English were excluded.

CONCLUSIONS

Conducting trials in children in LMICs is complex due to social disadvantage, economic scarcity, idiosyncratic cultural beliefs, and historical disempowerment, all of which contribute to inequity, mistrust, and fears of exploitation. Effective community engagement in recruiting, building research capacities, and designing trials that are pragmatic, ethical, and relevant to the health care needs of children in LMICs may help to improve the equity and health outcomes of this vulnerable population.

Willingness to participate in trials and to be vaccinated with new tuberculosis vaccines in HIV-infected adults

BACKGROUND

New tuberculosis (TB) vaccines are required to meet global targets for TB control.

OBJECTIVES

To determine willingness to participate (WTP) in new TB vaccine trials, willingness to be vaccinated with a newly licensed TB vaccine and associated factors among human immunodeficiency virus (HIV) infected persons.

SETTING

Two primary care clinics in South Africa.

DESIGN

Cross-sectional study design. Participants were asked about WTP and willingness to be vaccinated. Demographic, clinical, knowledge of TB and perception of risk information were collected. Log binomial regression was used to determine associated factors.

RESULTS

A total of 827 participants were included in the analysis: 80.4% female, 72.2% on antiretroviral therapy, median age 35 years (interquartile range [IQR] 29-42 years), CD4 count 523 cells/µl (IQR 427-659 cells/µl). WTP and willingness to be vaccinated were high, at 84.5% and 92.6%, respectively. WTP was associated with knowledge about TB (prevalence ratio [PR] 1.10, 95% confidence interval [CI] 1.03-1.17) and perception of risk (PR 1.07, 95%CI 1.01-1.13). Willingness to be vaccinated was associated with employment (PR 1.04, 95%CI 1.01-1.08) and perception of risk (PR 1.05, 95%CI 1.01-1.09).

CONCLUSIONS

There was high WTP in TB vaccine trials and willingness to be vaccinated among HIV-infected patients with good TB knowledge and high perceived risk of contracting TB.

Knowledge, attitudes and practices on adolescent vaccination among parents, teachers and adolescents in Africa: a systematic review protocol

BACKGROUND

Vaccines are the most successful and cost-effective public health interventions available to avert vaccine-preventable diseases and deaths. Despite progress in the field of adolescent health, many young people in Africa still get sick and die from vaccine-preventable diseases due to lack of vaccination. Parents, adolescents and teachers are key players with regard to implementation of adolescent vaccination policies. Therefore, understanding their knowledge, attitudes and practices towards adolescent vaccination may provide clues on what can be done to improve vaccine uptake among adolescents. The aim of this study is to conduct a qualitative and quantitative systematic review on knowledge, attitudes and practices on adolescent vaccination among parents, teachers and adolescents in Africa.

METHODS

We will include both quantitative and qualitative primary studies. Eligible quantitative studies include both intervention and observational studies. Qualitative studies to be included are focus group discussions, direct observations, in-depth interviews and case ethnographic studies. We will search PubMed, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, WHOLIS, Africa Wide and CINAHL for eligible studies with no time and language limits. We will also check reference lists of included studies for other eligible reports. Two authors will independently screen the search output, select studies and extract data, resolving discrepancies by consensus and discussion. We will analyse qualitative data using thematic analysis where applicable, and quantitative studies findings will be presented in a narrative synthesis form based on the outcomes.

DISCUSSION

The findings from this systematic review will guide the identification of gaps on knowledge, attitudes and practices among the key role players on adolescent vaccination. We anticipate that our findings will guide the development of adolescent-focused vaccination policy in Africa, which is virtually non-existent at present.

SYSTEMATIC REVIEW REGISTRATION

This review is registered with PROSPERO, registration number CRD42014010395.