Microarray patches: scratching the surface of vaccine delivery

Amplifying youth voices: young people's recommendations for policy and practice to enhance vaccine acceptability

BACKGROUND

The COVID-19 pandemic has underscored the need for increased vaccine availability and uptake, with vaccine hesitancy posing a significant barrier, particularly among young adults. Evidence from various countries highlight high levels of hesitancy among young people, necessitating targeted interventions. Engaging young adults as key stakeholders in shaping public health strategies is crucial, as their perspectives can enhance vaccine acceptance. This study aimed to assess the overall acceptability of the COVID-19 vaccine among young people and to explore the factors influencing their willingness or reluctance to be vaccinated now and in the future.

METHODS

This study used qualitative data from 165 young adults in Nigeria, South Africa, and Zambia, to explore their suggestions for policies and strategies aimed at enhancing the acceptance of the Covid-19 vaccination among their age group. Data collection involved focus groups and interviews that explored participants' perceptions and recommendations regarding COVID-19 vaccination acceptability. Thematic analysis was used to analyse the data.

RESULTS

Thematic analysis identified several factors influencing vaccine acceptability among young people and suggested recommendations to improve it. The themes included developing targeted communication strategies for accurate vaccine information, offering alternative vaccination methods, promoting vaccine education in schools, and using trusted public figures to share accurate information.

CONCLUSIONS

Persistent dissatisfaction with vaccine information dissemination underscores the need for more targeted communication strategies among young adults. Recommendations include developing non-injection vaccine options, incorporating vaccine education into school curricula and community programs, and leveraging influential public figures to build credibility. These insights are valuable for designing future programs to enhance vaccine acceptance among adolescents.

An Application of an Initial Full Value of Vaccine Assessment Methodology to Measles-Rubella MAPs for Use in Low- and Middle-Income Countries

Measles and rubella micro-array patches (MR-MAPs) are a promising innovation to address limitations of the current needle and syringe (N&S) presentation due to their single-dose presentation, ease of use, and improved thermostability. To direct and accelerate further research and interventions, an initial full value vaccine assessment (iFVVA) was initiated prior to MR-MAPs entering phase I trials to quantify their value and identify key data gaps and challenges. The iFVVA utilized a mixed-methods approach with rapid assessment of literature, stakeholder interviews and surveys, and quantitative data analyses to (i) assess global need for improved MR vaccines and how MR-MAPs could address MR problem statements; (ii) estimate costs and benefits of MR-MAPs; (iii) identify the best pathway from development to delivery; and (iv) identify outstanding areas of need where stakeholder intervention can be helpful. These analyses found that if MR-MAPs are broadly deployed, they can potentially reach an additional 80 million children compared to the N&S presentation between 2030-2040. MR-MAPs can avert up to 37 million measles cases, 400,000 measles deaths, and 26 million disability-adjusted life years (DALYs). MR-MAPs with the most optimal product characteristics of low price, controlled temperature chain (CTC) properties, and small cold chain volumes were shown to be cost saving for routine immunization (RI) in low- and middle-income countries (LMICs) compared to N&S. Uncertainties about price and future vaccine coverage impact the potential cost-effectiveness of introducing MR-MAPs in LMICs, indicating that it could be cost-effective in 16-81% of LMICs. Furthermore, this iFVVA highlighted the importance of upfront donor investment in manufacturing set-up and clinical studies and the critical influence of an appropriate price to ensure country and manufacturer financial sustainability. To ensure that MR-MAPs achieve the greatest public health benefit, MAP developers, vaccine manufacturers, donors, financiers, and policy- and decision-makers will need close collaboration and open communications.

Developing and validating a scale to measure the perceptions of safety, usability and acceptability of microarray patches for vaccination: a study protocol

Background

Vaccination is a fundamental tenet of public and population health. Several barriers to vaccine uptake exist, exacerbated post-COVID-19, including misconceptions about vaccine efficacy and safety, vaccine hesitancy, vaccine inequity, costs, religious beliefs, and insufficient education and guidance for healthcare professionals. Vaccine uptake may be aided using microarray patches (MAPs) due to reduced pain, no hypodermic needle, enhanced thermostability, and potential for self and lay administration.

Objectives

This protocol outlines the development of a scale that aims to accurately measure the perceived safety, usability, and acceptability of MAPs for vaccination among laypeople, MAP recipients, clinicians, and parents or guardians of children.

Methods and analysis

This study will follow three phases of scale development and validation, including (1) item development, (2) scale development, and (3) scale evaluation. Inductive (interviews) and deductive methods (literature searches) will be used to develop scale items, which experts from target populations will assess through an online survey. Cognitive interviews will be conducted to observe their processes of answering the draft survey. Thematic analysis will be conducted to analyse qualitative data. Lastly, four surveys will be administered online to our target populations over two time points to determine their repeatability. Exploratory and confirmatory factor analyses, Cronbach's alpha, and construct validity will be performed.

Ethics

This study was approved by Metro South Health (HREC/2021/QMS/81653) and Western Sydney Local Health District (2023/ETH00705) Human Research Ethics Committees.

Discussion

The scale will support a standardised approach to assessing the social and behavioural aspects of MAP vaccines, enabling comparison of outcomes across studies. Once validated, this scale will assist vaccination programmes in developing effective strategies for integrating MAPs and overcoming barriers to vaccination. This includes improving vaccine equity and accessibility, especially in lower- and middle-income countries and rural or remote locations.

Enhancement of cellular immunity following needle-free vaccination of mice with SARS-CoV-2 spike protein

The COVID-19 pandemic has highlighted the need for vaccines capable of providing rapid and robust protection. One way to improve vaccine efficacy is delivery via microarray patches, such as the Vaxxas high-density microarray patch (HD-MAP). We have previously demonstrated that delivery of a SARS-CoV-2 protein vaccine candidate, HexaPro, via the HD-MAP induces potent humoral immune responses. Here, we investigate the cellular responses induced by HexaPro HD-MAP vaccination. We found that delivery via the HD-MAP induces a type one biassed cellular response of much greater magnitude as compared to standard intramuscular immunization.