Socioeconomic inequalities in healthcare system efficiency in Japan during COVID-19 pandemic: an analysis of the moderating role of vaccination.

Background: In the context of the COVID-19 pandemic, limited research has focused on socioeconomic disparities in Local Healthcare System Efficiency (LHSE) among Japanese prefectures. This study seeks to investigate the moderating impact of vaccination on the relationship between LHSE and socioeconomic characteristics and endowments. Methods: To explore these relationships, we first utilized the Data Envelopment Analysis with Slack-Based Measure to measure the LHSE, based on data from Japanese prefectures during waves 2 to 5 of the pandemic. Then estimating the impact of socioeconomic variables on LHSE. Finally, we assessed the changes in the way socioeconomic variables affect LHSE before and after vaccine deployment using the Seemingly Unrelated Estimation t-test methodology. Results: The research findings suggest an overall reduction in LHSE disparities across various regions due to the utilization of vaccines. Particularly in areas with relatively nsufficient bed resources, a significant improvement in LHSE was observed in most regions. However, there was no evidence supporting the role of vaccine deployment in mitigating socioeconomic inequalities in LHSE. Conversely, the utilization of vaccines showed a positive correlation between the improvement in LHSE and the proportion of older adult population in regions with sufficient bed resources. In regions facing bed shortages, the enhancement of LHSE became more reliant on reducing the occupancy rate of secured beds for severe cases after the introduction of vaccination. Discussion: In regions facing bed shortages, the enhancement of LHSE became more reliant on reducing the occupancy rate of secured beds for severe cases. This underscores the importance for policymakers and implementers to prioritize the treatment of severe cases and ensure an effective supply of medical resources, particularly secured beds for severe cases, in their efforts to improve LHSE, in the post-COVID-19 era with rising vaccine coverage.

RISE-Vac-Co-production of Vaccine Education Materials with Persons Living in Prison.

Increasing vaccination knowledge is effective in addressing hesitancy and is particularly important in populations deprived of liberty who may not routinely have access to health information, ensuring health equity. RISE-Vac is a European Union-funded project aiming to promote vaccine literacy, offer, and uptake in prisons in Europe. We consulted persons living in prisons in the United Kingdom (through the Prisoner Policy Network), France, and Moldova to determine their vaccination knowledge gaps, the information they would like to receive, and how they would like to receive it. We received 344 responses: 224 from the United Kingdom, 70 from France, and 50 from Moldova. Participants were particularly interested in learning about the effectiveness, side effects, and manufacturing of vaccines. Their responses guided the development of educational materials, including a brochure that will be piloted in prisons in Europe. Persons with experience of imprisonment were involved at every stage of this project.

COVID-19 Vaccine Injury Compensation Program: Lessons Learned From a Review of 10 Implementing Countries.

National vaccine injury compensation serves as a crucial and significant safety net for individuals affected by government-recommended vaccines during a pandemic, contributing to the community's overall safety. In the Republic of Korea, compensation for adverse events resulting from coronavirus disease 2019 (COVID-19) vaccinations has been provided through the National Vaccine Injury Compensation Program introduced in 1995. However, there have been limitations with these measures during the COVID-19 pandemic owing to strict criteria for substantiating causality between the vaccine and injury, its nontransparent process of determining whether to compensate, and the compensation amount that is not practically calculated. This article reviewed the Vaccine Injury Compensation Programs in 10 major countries to present implications for improving the Korean system. Expanding the scope of national accountability is essential to compensate for the consequences of adhering to national policies during public health crises. Therefore, valuable insight can be obtained from examining the systems in Germany, Japan, and Taiwan, which have implemented more relaxed criteria for determining causality in compensation cases; Thailand's system, which provides the mandatory payment of preliminary compensation for damage caused by vaccination; systems in Germany, France, and Japan, which offer compensation for vaccine injuries from a practical perspective; and systems in France and the United Kingdom, which have a process allowing the assessment records to be shared with the claimants. Furthermore, a dedicated agency for vaccine injury compensation, as seen in France, the United Kingdom, and Australia, is necessary to enhance the efficiency of the Korean system.

Assessment of prevalence and risk factors associated with Hepatitis B virus infection among blood donors in Mogadishu Somalia.

BACKGROUND: The Hepatitis B virus (HBV) is transmitted through contaminated blood or bodily fluids. Globally, over 81 million blood units are donated annually, a crucial therapeutic procedure without alternatives. However, blood-borne infections, including HBV, pose a significant hurdle to safe transfusions, especially in HBV-endemic regions like Somalia with limited screening. Therefore, this study aims to estimate the prevalence of Hepatitis B virus infection and identify risk factors associated with it among blood donors in Mogadishu, Somalia. METHOD: A hospital-based cross-sectional study was conducted between February and April 2023. Research tools included a 5-ml blood sample and a structured questionnaire. The presence or absence of HB markers was determined using a multi-HB rapid test and CDC's HB marker interpretation guideline. Logistic regression was used in univariate and multivariate models to identify risk factors associated with HBV infection, with significance set at a p-value < 0.05 in the final model. RESULT: A total of 494 blood donors were recruited for this study; 93.9% were male, with a mean age of 31.5 (SD = 8.11). The prevalence of Hepatitis B virus (HBV) infection among blood donors was 9.7%, with a 95% CI of 7.1-12.3. In multivariable logistic regression, those with a monthly income of less than 200 USD (AOR = 5.20, 95% CI = 1.61-16.79), those with an income between 200 and 400 (AOR = 3.59, 95% CI = 1.38-9.34), Jobless blood donors (AOR = 3.78, 95% CI = 1.17-12.20), those in business occupations (AOR = 3.35, 95% CI = 1.24-9.08), those with a history of STDs (AOR = 4.83, 95% CI = 2.03-11.50), those without a history of HB vaccine (AOR = 13.81, 95% CI = 2.46-77.41), those with a history of tooth extraction (AOR = 6.90, 95% CI = 2.66-17.88), and those who shared sharp equipment (AOR = 2.90, 95% CI = 1.07-7.82) were more likely to become infected with the Hepatitis B virus (HBV) compared to their counterparts. CONCLUSION: This study highlights a high prevalence of Hepatitis B virus (HBV) infection. Implementation efforts against HBV infection should specifically focus on low-income individuals, the jobless, and donors with a history of STD to mitigate the burden of HBV infection and promote safer blood donation. In addition, discouraging the sharing of sharp equipment, improving infection control practices during tooth extraction procedures, and enhancing HB vaccination uptake, particularly among individuals lacking a history of HB vaccine, is highly recommended.

Population-based cross-sectional study of factors influencing full vaccination status of children aged 12- 23 months in a rural district of the Upper East Region, Ghana.

BACKGROUND: Achieving universal health coverage includes ensuring that children have access to vaccines that are of high quality, safe, efficacious, and affordable. The Immunisation Agenda 2030 aims to expand services to zero-dose and incompletely vaccinated children and reduce immunisation rate disparities as a contribution to vaccination equity. This study explored the factors influencing full vaccination status among children aged 12 - 23 months in a rural district of the Upper East Region of Ghana. METHODS: A population-based cross-sectional study was conducted among carers of children aged 12 -23 months in the Kassena Nankana West district. A multistage sampling technique was used to select 360 carers. Information regarding the vaccination status of children was gathered through a combination of children's health record books and carers' recollections. Information on potential determinants was also systematically collected for analysis in Stata version 15.0. RESULTS: The results showed that 76.9% (95% CI: 72.3 - 81.0) of children had full vaccinations per the national schedule. All children received at least one vaccination. A higher percentage of carers with incompletely vaccinated children reported that they had travelled with their children as the primary reason for missing certain vaccine doses. Full vaccination status was significantly associated with secondary (aOR = 2.60; 95% CI: 1.20-5.63) and tertiary (aOR = 3.98, 95% CI: 1.34-11.84) maternal educational level, being in a partnership relationship (aOR = 2.09, 95% CI: 1.03-4.25), and residing in close proximity to healthcare facilities (aOR = 0.41, 95% CI: 0.21-0.80). CONCLUSIONS: Our study found that nearly one-quarter of children aged 12-23 months in the study setting are underserved with vaccination services for a variety of reasons. Effectively reaching these children will require strengthening health systems, including eliminating vaccine shortages, addressing the unique challenges faced by unmarried women with children aged 12-23 months, and improving accessibility to vaccination services.

[Cost-effectiveness analysis of a vaccine for Helicobacter pylori in southern Europe]. / Análisis coste-efectividad de una vacuna para Helicobacter pylori en el sur de Europa.

OBJECTIVE: There is sufficient evidence on the feasibility of a vaccine to prevent Helicobacter pylori infection. Modeling studies in low prevalence environments report a very probable long-term cost-effectiveness. The objective of this study was to quantify its efficiency in a local context. METHODS: The evolution of a cohort of newborns was simulated through a compartmental model representing a series of clinical situations regarding H. pylori infection and related diseases. The model was run under the assumption of both vaccination in the first year of life and no intervention. The time horizon was set as equivalent to the life expectancy and the perspective of the health system was taken into account. RESULTS: Vaccination against H. pylori would cost an average of €2,168/person more than no intervention. This would yield an average additional 0.32 quality-adjusted life years gained (QALY), which would entail an incremental cost-effectiveness ratio (ICER) of €7,196/QALY. For a willingness to pay of €24,506/QALY, 99.96% of the simulations were cost-effective at eighty-four years old. This threshold was crossed thirty years after vaccination. The variables that carried the most weight in explaining the variability of the ICER were, in this order, vaccine effectiveness, the incidence of infection in young children, and the price of the vaccine. Vaccination would cease to be cost-effective with a price greater than €3,634/dose or with effective population coverage less than 11%. CONCLUSIONS: When implemented in an environment with the epidemiological and economic characteristics of Southern Europe, a prophylactic vaccination against H. pylori would be cost-effective in the long run.

OBJECTIVE: Existen pruebas de la factibilidad de una vacuna para prevenir la infección por Helicobacter pylori. Modelizaciones en entornos de baja prevalencia informan de una muy probable coste-efectividad a largo plazo. El objetivo de este estudio fue cuantificar su eficiencia en un contexto local. METHODS: Se simuló la evolución de una cohorte de nacidos a través de un modelo compartimental representativo de varios estados clínicos en relación a la infección por H. pylori. Se ejecutó dicho modelo bajo las premisas de vacunación en el periodo de lactante y de no intervención. El horizonte temporal fue equivalente a la esperanza de vida y se tuvo en cuenta la perspectiva del sistema de salud. RESULTS: La vacunación frente a H. pylori costaría de media 2.168 €/persona más que la no intervención. Con ello se obtendrían 0,32 años de vida ganados ajustados por calidad (AVAC), lo que implicaría una razón de coste-efectividad incremental (RCEI) media de 7.196 €/AVAC. Para una disposición a pagar de 24.506 €/AVAC, el 99,96% de las simulaciones resultaron coste-efectivas al alcanzar el horizonte temporal y se cruzó dicho umbral a partir de los treinta años de la vacunación. Las variables que más peso tuvieron para explicar la variabilidad de la RCEI fueron, en este orden, la efectividad vacunal, la incidencia de la infección en la primera infancia y el precio de la vacuna. La vacunación dejaría de ser coste-efectiva con un precio mayor de 3.634€/vial o con una cobertura poblacional efectiva menor del 11%. CONCLUSIONS: Una vacunación frente a la infección por H. pylori administrada en la infancia sería coste-efectiva a largo plazo en un entorno con las características epidemiológicas y económicas del sur de Europa.

The Impact of the Medicaid Reimbursement Bump on Influenza Vaccination Rates Among US Teens: Evidence from the National Immunization Survey-Teen 2011-2020.

BACKGROUND: Many adolescents do not receive basic preventive care such as influenza vaccinations. The Affordable Care Act (ACA) temporarily increased Medicaid reimbursements for primary care services, including vaccine administration, in 2013 to 2014. The objective of this study is to assess the impact of reimbursement increases on influenza vaccination rates among adolescents with Medicaid. METHODS: This repeated cross-sectional study used a difference-in-difference approach to compare changes in annual influenza vaccination rates for 20,884 adolescents 13 to 17 years old covered by Medicaid with adequate provider-reported data in 18 states with larger extended (>$5, 2013 to 2019) versus larger temporary (2013 to 2014 only) versus smaller reimbursement changes. We used linear probability models with individual-level random effects, adjusting for state and individual characteristics and annual time trends to assess the impact of a Medicaid vaccine administration reimbursement increase on annual influenza vaccination. RESULTS: Mean Medicaid reimbursements for vaccine administration doubled from 2011 to 2013 to 2014 (eg, from $11 to $22 for CPT 90460). States with smaller reimbursement changes had higher mean reimbursements and higher adjusted vaccination rates at baseline (2011) compared with states with larger temporary and extended reimbursement changes. The reimbursement change was not associated with increases in influenza vaccination rates. DISCUSSION: Influenza vaccination rates were low among adolescents with Medicaid throughout the study period, particularly in states with lower Medicaid reimbursement levels before the ACA. CONCLUSION: That reimbursement increases were not associated with higher vaccination rates suggests additional efforts are needed to improve influenza vaccination rates in this population.

Advancing the National Immunization Program in an era of achieving universal vaccine coverage in China and beyond.

BACKGROUND: Immunization is a cornerstone of public health. Despite great success, China's National Immunization Program (NIP) faces challenges, such as the integration of several World Health Organization-recommended vaccines and other systemic issues. The Innovation Laboratory for Vaccine Delivery Research (VaxLab), supported by the Bill & Melinda Gates Foundation and established in 2021 at Duke Kunshan University, focuses on enhancing China's NIP through research and policy advocacy. This editorial aims to summarize the key findings of the manuscripts published in the collection contributed by VaxLab team and set the future research agenda. KEY FINDINGS: The collection contains eleven manuscripts discussing China's immunization landscape and strategies to improve coverage, particularly for non-NIP vaccines like human papillomavirus vaccine (HPV), pneumococcal conjugate vaccine (PCV), Haemophilus influenzae type b vaccine (Hib), and rotavirus vaccines. Key findings include: (i) The COVID-19 vaccination campaign demonstrated China's capacity for rapid, large-scale immunization efforts, suggesting potential for broader vaccine coverage improvements; (ii) Efforts in combating cervical cancer through the HPV vaccine indicate progress but also highlight challenges like vaccine supply and equitable access; (iii) The lag in adopting higher-valent paediatric combination vaccines in China needs attention to address regulatory and health system hurdles; (iv) Disparities in access to non-NIP vaccines underscore the need for government initiatives to improve vaccine coverage, especially for remote areas and marginalized populations; (v) Original studies emphasize the influence of caregivers' knowledge, health workers' financial incentives, and concerns about vaccine efficacy on immunization rates; (vi) Case studies from the Weifang City of China and Indonesia to introduce PCV offer insights on successful vaccine introduction strategies and the impact of innovative financing and government support. CONCLUSION: The articles emphasize the need for government leadership, strategic policymaking, and public awareness to enhance vaccine coverage and equity. The VaxLab will continue strengthening China's NIP by focusing on vaccine financing, emphasizing diversity, equity, and inclusion, and improving maternal vaccination coverage. Research will extend to Southeast Asian and Western Pacific regions, especially in middle-income countries facing challenges in vaccine financing and delivery. The collective efforts outlined in this collection show a commitment to evolving and adapting immunization strategies to meet global health goals and to provide equitable access to vaccines for all.

A community-engaged approach to translate a Vaccine Hesitancy Scale into Haitian Creole.

OBJECTIVE: Accurately translated health materials are needed to achieve equity in vaccine uptake among U.S. individuals with non-English language preferences. Verbatim translations may not capture the cultural and linguistic vernacular required to understand vaccine hesitancy. We leveraged a community-engaged approach to translate the Vaccine Hesitancy Scale (VHS) into Haitian Creole. METHODS: Following the "WHO Guidelines on Translation and Adaptation of Instruments" and a community-engaged framework, a validated 10-question Vaccine Hesitancy Scale (VHS) underwent forward translation, expert panel review, back translation, and focus group pilot testing. RESULTS: Haitian Creole-speaking translators included two community leaders, one community partner, one study team member, and 13 Haitian, greater Boston-based community members who participated in a focus group to pretest the survey. After four iterations, a linguistic and cultural translation of the VHS was created. CONCLUSION: A community-engaged framework strengthened community partnerships and resulted in a culturally relevant Haitian Creole vaccine hesitancy scale.

Positioning implementation science in national immunization programmes to improve coverage equity and advance progress toward Immunization Agenda 2030: An urgent global health imperative.

Despite the availability of effective vaccines for preventing common childhood infectious diseases, there is still significant disparities in access and utilization across many low- and middle-income countries (LMIC). The factors that drive these disparities are often multilevel, originating from individuals, health facilities, health systems and communities, and also multifaceted. Implementation science has emerged as a field to help address "know-do" gaps in health systems, and can play a significant role in strengthening immunization systems to understand and solve implementation barriers that limit access and uptake within their contexts. This article presents a reflexive perspective on how to position implementation research in immunization programmes to improve coverage equity. Furthermore, key points of synergy between implementation research and vaccination are highlighted, and some potential practice changes that can be applied within specific contexts were proposed. Using a human rights lens, it was concluded that the cost that is associated with implementation failure in immunization programmes is significant and unjust, and future directions for implementation research to optimize its application in practice settings have been recommended.

Cross-Reactivity Assessment of Vaccine-Derived SARS-CoV-2 T Cell Responses against BA.2.86 and JN.1.

The SARS-CoV-2 Omicron sub-variants BA.2.86 and JN.1 contain multiple mutations in the spike protein that were not present in previous variants of concern and Omicron sub-variants. Preliminary research suggests that these variants reduce the neutralizing capability of antibodies induced by vaccines, which is particularly significant for JN.1. This raises concern as many widely deployed COVID-19 vaccines are based on the spike protein of the ancestral Wuhan strain of SARS-CoV-2. While T cell responses have been shown to be robust against previous SARS-CoV-2 variants, less is known about the impact of mutations in BA.2.86 and JN.1 on T cell responses. We evaluate the effect of mutations specific to BA.2.86 and JN.1 on experimentally determined T cell epitopes derived from the spike protein of the ancestral Wuhan strain and the spike protein of the XBB.1.5 strain that has been recommended as a booster vaccine. Our data suggest that BA.2.86 and JN.1 affect numerous T cell epitopes in spike compared to previous variants; however, the widespread loss of T cell recognition against these variants is unlikely.

Safety Assessment: a Comparative Analysis of Quantitative Content of Bacterial Endotoxins and Evaluation of Pyrogenicity of the Kazakhstan Vaccine QazCovid-in® against COVID-19.

We measured the levels of bacterial endotoxins in the bulk vaccine product (BVP) and finished vaccine QazCovid-in® and evaluated the effect of aluminum hydroxide (adjuvant) on the results of LAL test and pyrogenicity of samples in vivo (in rabbits receiving intravenous injection into the marginal ear vein). Administration of BVP with LPS resulted in a dose-dependent increase in body temperature in rabbits similar to that caused by LPS alone, which suggests that aluminum hydroxide in the vaccine did not affect the pyrogenic response in rabbits. Moreover, the LAL test showed that the aluminum hydroxide did not hinder LPS activity after serial dilution of samples.

Assessment of the comprehensiveness of paediatric national immunisation programmes in Europe: expert validation and future perspectives.

BACKGROUND: The breadth of protection of National Immunisation Programmes (NIPs) across Europe varies, however, this has not been assessed within published literature. Therefore, a framework was developed to assess the comprehensiveness of pediatric NIPs in Europe. This study aimed to validate and further develop criteria used to cluster countries into three tiers. RESEARCH DESIGN AND METHODS: Independent Europe-based experts (n = 23) in the field of pediatric vaccination were invited to participate in a double-blinded modified Delphi panel, with two online survey rounds and a virtual consensus meeting. Consensus was defined as ≥ 80% of experts rating their agreement/disagreement on a 9-point Likert scale. RESULTS: The number of preventable diseases covered by an NIP, simplification of the vaccination calendar, strengthened protection by increasing serotype, degree of funding and epidemiological factors were considered key concepts for consideration of the comprehensiveness of pediatric NIPs in Europe. Experts highlighted that the framework should be extended to include adolescent vaccines and populations up to 18 years of age. Consensus regarding further amendments to the framework was also reached. CONCLUSIONS: This Delphi panel validated a framework to assess the comprehensiveness of European NIPs. The framework can be used to facilitate discussions to help countries improve and expand the breadth of protection provided by their NIP.

Impact and cost-effectiveness analyses of vaccination for prevention of respiratory syncytial virus disease among older adults in Ontario: A Canadian Immunization Research Network (CIRN) study.

BACKGROUND: Two prefusion F protein-based vaccines, Arexvy and Abrysvo, have been approved by Health Canada for protecting older adults against respiratory syncytial virus (RSV)-associated lower respiratory tract disease. We estimated the health benefits and cost-effectiveness of these vaccines under a publicly funded single-dose vaccination program in Ontario that targets residents of long-term care homes (LTCHs). Additionally, we evaluated an extended program that broadens vaccination to include community-dwelling older adults. METHODS: A discrete-event simulation model was parameterised with the burden of RSV disease including outpatient care, hospitalisation, and death among adults aged 60 years or older in Ontario, Canada. Accounting for direct and indirect costs (in 2023 Canadian dollars) associated with RSV-related outcomes, we calculated the net monetary benefit using quality-adjusted life-year (QALY) gained, and determined the range of price-per-dose (PPD) for vaccination programs to be cost-effective from both healthcare and societal perspectives over two RSV seasons. The incremental cost-effectiveness ratio (ICER) was calculated to estimate the additional costs required to gain one QALY. RESULTS: Using a willingness-to-pay of $50,000 per QALY gained, we found that vaccinating 90% of residents in LTCHs with Arexvy would be cost-effective from a societal perspective for a PPD up to $163, producing a mean ICER value of $49,984 (95% CI: $47,539 to $52,704) per QALY gained with a two-year budget impact of $463,468 per 100,000 older adults. The reduction of hospitalizations was estimated at 7.0% compared to the no-vaccination scenario. Extending the program to include community-dwelling older adults with a 74% coverage akin to influenza vaccination, Arexvy remains cost-effective for a PPD up to $139, with a mean ICER value of $49,698 (95% CI: 48,022 to 51,388) per QALY gained and a two-year budget impact of $8.63 million. Compared to the no-vaccination scenario, the extended program resulted in a 57.3% reduction in RSV-related hospitalisations. CONCLUSIONS: Vaccinating residents of LTCHs against RSV disease would be cost-effective depending on PPD; extending the program to community-dwelling older adults would provide substantial health benefits, averting significant direct healthcare costs and productivity losses.

Vaccination strategies for high-risk and fragile populations in Lombardy (Italy): a region-wide assessment of hospital-based models and best practices.

Background: Subjects with selected underlying medical conditions are at higher risk of infection and severe outcomes from vaccines preventable diseases. While most countries adopt life-course approaches to vaccination, high-risk group immunization programmes could maximize individual protection, while contributing to population health. The COVID-19 pandemic stimulated the planning and implementation of successful hospital-based high-risk groups' immunization models. However, in Italy, high-risk subjects' vaccine coverage is not actively monitored at the national or regional level, nor shared guidelines exist yet on hospital-based immunization programmes. Study Design: The study reports findings from a region-wide assessment of the availability, characteristics, and setting-specific features of hospital-based immunization programmes for high-risk subjects in the Lombardy region. Methods: Fondazione The Bridge a not-for-profit organization based in Milan, in collaboration with the Prevention Unit of the Lombardy Region Directorate for Welfare, and the University of Pavia coordinated a project aimed at bringing together regional health institutions, key stakeholders, academic experts, scientific societies and patients' associations to assess high-risk subjects' barriers to vaccine uptake and inform preventive programmes and policies. In this context, we designed and implemented a survey to systematically map the existence and characteristics of hospital-based immunization programmes targeting high-risk subjects. The survey was proposed to all 115 hospital medical directions of the Lombardy region. Results: We collected data from 97 hospital medical directions, with a response rate of 85%. Among respondents, 24% were publi-cly managed hospitals, 17% were Scientific Institute for Research, Hospitalization and Healthcare (IRCCS) and 59% accredited private hospitals. Overall, 51.5% facilities in the Lombardy Region reported to actively administer vaccines to high-risk subjects in hospital settings, the prevalence being 89.6% in public hospitals. Among hospitals where vaccines are actively administered, 46% reported to have centralized vaccines ambulatory clinics, while 54% reported to administer vaccines in the context of inpa-tient care, within clinical wards. In 14% of hospitals vaccination counselling is carried out at the hospital level, while patients are referred to community services for the vaccine administration, 58% have established clinical pathways and formalized internal procedures to integrate vaccine prevention within the clinical care. Conclusions: Half of hospital facilities in the Lombardy Region administer vaccines to high-risk patients. Hospital-based im-munization models vary widely by vaccines programmes, organizational aspects, vaccines procurement and workforce involved. Identifying best practices and effective models can help tackle current challenges and improve immunization coverage for at-risk groups.

Value of information dynamics in Disease X vaccine clinical trials.

BACKGROUND: Solutions have been proposed to accelerate the development and rollout of vaccines against a hypothetical disease with epidemic or pandemic potential called Disease X. This may involve resolving uncertainties regarding the disease and the new vaccine. However the value for public health of collecting this information will depend on the time needed to perform research, but also on the time needed to produce vaccine doses. We explore this interplay, and its effect on the decision on whether or not to perform research. METHOD: We simulate numerically the emergence and transmission of a disease in a population using a susceptible-infected-recovered (SIR) compartmental model with vaccination. Uncertainties regarding the disease and the vaccine are represented by parameter prior distributions. We vary the date at which vaccine doses are available, and the date at which information about parameters becomes available. We use the expected value of perfect information (EVPI) and the expected value of partially perfect information (EVPPI) to measure the value of information. RESULTS: As expected, information has less or no value if it comes too late, or (equivalently) if it can only be used too late. However we also find non trivial dynamics for shorter durations of vaccine development. In this parameter area, it can be optimal to implement vaccination without waiting for information depending on the respective durations of dose production and of clinical research. CONCLUSION: We illustrate the value of information dynamics in a Disease X outbreak scenario, and present a general approach to properly take into account uncertainties and transmission dynamics when planning clinical research in this scenario. Our method is based on numerical simulation and allows us to highlight non trivial effects that cannot otherwise be investigated.

Ethical Challenges of Advances in Vaccine Delivery Technologies.

Strategies to address misinformation and hesitancy about vaccines, including the fear of needles, and to overcome obstacles to access, such as the refrigeration that some vaccines demand, strongly suggest the need to develop new vaccine delivery technologies. But, given widespread distrust surrounding vaccination, these new technologies must be introduced to the public with the utmost transparency, care, and community involvement. Two emerging technologies, one a skin-patch vaccine and the other a companion dye and detector, provide excellent examples of greatly improved delivery technologies for which such a careful approach should be developed in order to increase vaccine uptake. Defusing fears and conspiracy mongering must be a key part of their rollout.

Serological assessment of the durability of vaccine-mediated protection against SARS-CoV-2 infection.

Virus-neutralizing antibodies are often accepted as a correlate of protection against infection, though questions remain about which components of the immune response protect against SARS-CoV-2 infection. In this small observational study, we longitudinally measured spike receptor binding domain (RBD)-specific and nucleocapsid (NP)-specific serum IgG in a human cohort immunized with the Pfizer BNT162b2 vaccine. NP is not encoded in the vaccine, so an NP-specific response is serological evidence of natural infection. A greater than fourfold increase in NP-specific antibodies was used as the serological marker of infection. Using the RBD-specific IgG titers prior to seroconversion for NP, we calculated a protective threshold for RBD-specific IgG. On average, the RBD-specific IgG response wanes below the protective threshold 169 days following vaccination. Many participants without a history of a positive test result for SARS-CoV-2 infection seroconverted for NP-specific IgG. As a group, participants who seroconverted for NP-specific IgG had significantly higher levels of RBD-specific IgG following NP-seroconversion. RBD-specific IgG titers may serve as one correlate of protection against SARS-CoV-2 infection. These titers wane below the proposed protective threshold approximately six months following immunization. Based on serological evidence of infection, the frequency of breakthrough infections and consequently the level of SARS-CoV-2-specific immunity in the population may be higher than what is predicted based on the frequency of documented infections.

Flexible and cost-effective genomic surveillance of P. falciparum malaria with targeted nanopore sequencing.

Genomic surveillance of Plasmodium falciparum malaria can provide policy-relevant information about antimalarial drug resistance, diagnostic test failure, and the evolution of vaccine targets. Yet the large and low complexity genome of P. falciparum complicates the development of genomic methods, while resource constraints in malaria endemic regions can limit their deployment. Here, we demonstrate an approach for targeted nanopore sequencing of P. falciparum from dried blood spots (DBS) that enables cost-effective genomic surveillance of malaria in low-resource settings. We release software that facilitates flexible design of amplicon sequencing panels and use this software to design two target panels for P. falciparum. The panels generate 3-4 kbp reads for eight and sixteen targets respectively, covering key drug-resistance associated genes, diagnostic test antigens, polymorphic markers and the vaccine target csp. We validate our approach on mock and field samples, demonstrating robust sequencing coverage, accurate variant calls within coding sequences, the ability to explore P. falciparum within-sample diversity and to detect deletions underlying rapid diagnostic test failure.