The public health value of vaccines beyond efficacy: methods, measures and outcomes

Disease Burden and Inpatient Management of Children with Acute Respiratory Viral Infections during the Pre-COVID Era in Germany: A Cost-of-Illness Study

Respiratory viral infections (RVIs) are common reasons for healthcare consultations. The inpatient management of RVIs consumes significant resources. From 2009 to 2014, we assessed the costs of RVI management in 4776 hospitalized children aged 0-18 years participating in a quality improvement program, where all ILI patients underwent virologic testing at the National Reference Centre followed by detailed recording of their clinical course. The direct (medical or non-medical) and indirect costs of inpatient management outside the ICU ('non-ICU') versus management requiring ICU care ('ICU') added up to EUR 2767.14 (non-ICU) vs. EUR 29,941.71 (ICU) for influenza, EUR 2713.14 (non-ICU) vs. EUR 16,951.06 (ICU) for RSV infections, and EUR 2767.33 (non-ICU) vs. EUR 14,394.02 (ICU) for human rhinovirus (hRV) infections, respectively. Non-ICU inpatient costs were similar for all eight RVIs studied: influenza, RSV, hRV, adenovirus (hAdV), metapneumovirus (hMPV), parainfluenza virus (hPIV), bocavirus (hBoV), and seasonal coronavirus (hCoV) infections. ICU costs for influenza, however, exceeded all other RVIs. At the time of the study, influenza was the only RVI with antiviral treatment options available for children, but only 9.8% of influenza patients (non-ICU) and 1.5% of ICU patients with influenza received antivirals; only 2.9% were vaccinated. Future studies should investigate the economic impact of treatment and prevention of influenza, COVID-19, and RSV post vaccine introduction.

Comprehensive childhood vaccination and its determinants: Insights from the Indonesia Family Life Survey (IFLS)

BACKGROUND

Immunization is the most effective intervention for reducing morbidity and mortality rates associated with vaccine-preventable diseases. Despite the Indonesian government's inclusion of several childhood vaccinations in the national immunization program (NIP), the number of unvaccinated or partially vaccinated children remains high. This observational study aimed to determine the completeness of childhood immunization and the factors influencing it in Indonesia.

METHODS

Data were extracted from the fifth wave of the Indonesia Family Life Survey (IFLS). The sample (n = 16,236) consists of children residing in 13 provinces, representing over 80% of Indonesia's population. The difference between groups was tested using the chi-square test. Logistic regression was performed to identify the variables associated with the completeness of basic immunization. Immunization is categorized as complete when children have received all the mandatory vaccines recommended by the Ministry of Health. We examined and compared the results using complete case analysis, inverse probability weighting, and multiple imputations.

RESULTS

The highest percentages of complete vaccinations were polio, tuberculosis, and DPT. Children who live in Sumatera and Kalimantan were more likely to be fully immunized, with ORs of 0.6 (95%CI 0.48-0.74) and 0.54 (0.37-0.80), respectively. Children who live in urban areas, have mothers who received the tetanus vaccine during pregnancy, have mothers with a higher level of education and health insurance, have fathers aged 41-50, and live with a large number of family members were more likely to be fully immunized (p < 0.05).

CONCLUSION

Socioeconomic determinants were strongly correlated with the completeness of childhood vaccination in Indonesia.

Modeling Supply and Demand Dynamics of Vaccines against Epidemic-Prone Pathogens: Case Study of Ebola Virus Disease

Health emergencies caused by epidemic-prone pathogens (EPPs) have increased exponentially in recent decades. Although vaccines have proven beneficial, they are unavailable for many pathogens. Furthermore, achieving timely and equitable access to vaccines against EPPs is not trivial. It requires decision-makers to capture numerous interrelated factors across temporal and spatial scales, with significant uncertainties, variability, delays, and feedback loops that give rise to dynamic and unexpected behavior. Therefore, despite progress in filling R&D gaps, the path to licensure and the long-term viability of vaccines against EPPs continues to be unclear. This paper presents a quantitative system dynamics modeling framework to evaluate the long-term sustainability of vaccine supply under different vaccination strategies. Data from both literature and 50 expert interviews are used to model the supply and demand of a prototypical Ebolavirus Zaire (EBOV) vaccine. Specifically, the case study evaluates dynamics associated with proactive vaccination ahead of an outbreak of similar magnitude as the 2018-2020 epidemic in North Kivu, Democratic Republic of the Congo. The scenarios presented demonstrate how uncertainties (e.g., duration of vaccine-induced protection) and design criteria (e.g., priority geographies and groups, target coverage, frequency of boosters) lead to important tradeoffs across policy aims, public health outcomes, and feasibility (e.g., technical, operational, financial). With sufficient context and data, the framework provides a foundation to apply the model to a broad range of additional geographies and priority pathogens. Furthermore, the ability to identify leverage points for long-term preparedness offers directions for further research.

Acceptance of COVID-19 vaccine and associated factors among healthcare workers in Katsina state: a cross-sectional study in Northwest Nigeria

OBJECTIVES

Healthcare workers were prioritised to receive the COVID-19 vaccine in Nigeria. Administration of COVID-19 vaccination in Nigeria was challenging because of a lack of trust in vaccine safety and vaccine effectiveness among healthcare workers, who are expected to provide reliable information about vaccines and vaccine-preventable diseases in the communities. Hence, their acceptance and attitudes towards COVID-19 preventive practices could influence the acceptance of the vaccine by the local population. This cross-sectional study assessed the acceptance of the COVID-19 vaccine among healthcare workers in Katsina State. We predicted the variables that increased the vaccine acceptance using logistic regression analysis.

SETTING

This hospital-based study was conducted at primary, secondary and tertiary healthcare facilities in Nigeria.

PARTICIPANTS

A total of 793 healthcare workers were included in this study. Of these, 65.4% (n=519) were male.

OUTCOME MEASURES

To assess acceptance of COVID-19 vaccine measures, and factors increasing acceptance among healthcare workers.

RESULTS

Of the healthcare workers, 80% (638) were tested for the SARS-CoV-2, of whom 10.8% (n=65) tested positive. Approximately 97% (n=765) of them believed that the COVID-19 vaccine was safe, and 90% (n=714) received the first dose of the vaccine. Healthcare workers between 30 and 39 years were more likely to accept the vaccine (aOR: 7.06; 95% CI 2.36 to 21.07; p<0.001). Those who had been tested for COVID-19 were more likely (aOR:7.64; 95% CI 3.62 to 16.16; p<0.001) to accept the vaccine.

CONCLUSIONS

Our findings showed that the age and prior COVID-19 testing were the main factors influencing the acceptance of the COVID-19 vaccine. There was high acceptance of the COVID-19 vaccine among healthcare workers in Katsina State, Nigeria. Future studies should focus on the completion of doses and serological testing for immunity.

Measuring indirect transmission-reducing effects in tuberculosis vaccine efficacy trials: why and how?

Tuberculosis is the leading bacterial cause of death globally. In 2021, 10·6 million people developed symptomatic tuberculosis and 1·6 million died. Seven promising vaccine candidates that aim to prevent tuberculosis disease in adolescents and adults are currently in late-stage clinical trials. Conventional phase 3 trials provide information on the direct protection conferred against infection or disease in vaccinated individuals, but they tell us little about possible indirect (ie, transmission-reducing) effects that afford protection to unvaccinated individuals. As a result, proposed phase 3 trial designs will not provide key information about the overall effect of introducing a vaccine programme. Information on the potential for indirect effects can be crucial for policy makers deciding whether and how to introduce tuberculosis vaccines into immunisation programmes. We describe the rationale for measuring indirect effects, in addition to direct effects, of tuberculosis vaccine candidates in pivotal trials and lay out several options for incorporating their measurement into phase 3 trial designs.

Number needed to vaccinate with a COVID-19 booster to prevent a COVID-19-associated hospitalization during SARS-CoV-2 Omicron BA.1 variant predominance, December 2021-February 2022, VISION Network: a retrospective cohort study

Background

Understanding the usefulness of additional COVID-19 vaccine doses-particularly given varying disease incidence-is needed to support public health policy. We characterize the benefits of COVID-19 booster doses using number needed to vaccinate (NNV) to prevent one COVID-19-associated hospitalization or emergency department encounter.

Methods

We conducted a retrospective cohort study of immunocompetent adults at five health systems in four U.S. states during SARS-CoV-2 Omicron BA.1 predominance (December 2021-February 2022). Included patients completed a primary mRNA COVID-19 vaccine series and were either eligible to or received a booster dose. NNV were estimated using hazard ratios for each outcome (hospitalization and emergency department encounters), with results stratified by three 25-day periods and site.

Findings

1,285,032 patients contributed 938 hospitalizations and 2076 emergency department encounters. 555,729 (43.2%) patients were aged 18-49 years, 363,299 (28.3%) 50-64 years, and 366,004 (28.5%) ≥65 years. Most patients were female (n = 765,728, 59.6%), White (n = 990,224, 77.1%), and non-Hispanic (n = 1,063,964, 82.8%). 37.2% of patients received a booster and 62.8% received only two doses. Median estimated NNV to prevent one hospitalization was 205 (range 44-615) and NNV was lower across study periods for adults aged ≥65 years (110, 46, and 88, respectively) and those with underlying medical conditions (163, 69, and 131, respectively). Median estimated NNV to prevent one emergency department encounter was 156 (range 75-592).

Interpretation

The number of patients needed to receive a booster dose was highly dependent on local disease incidence, outcome severity, and patient risk factors for moderate-to-severe disease.

Funding

Funding was provided by the Centers for Disease Control and Prevention though contract 75D30120C07986 to Westat, Inc. and contract 75D30120C07765 to Kaiser Foundation Hospitals.

Multi-Perspective Views and Hesitancy toward COVID-19 Vaccines: A Mixed Method Study

The worldwide uptake of COVID-19 vaccines was suboptimal throughout the pandemic; vaccine hesitancy played a principle role in low vaccine acceptance both globally and in Armenia. In order to understand the factors behind the slow vaccine uptake in Armenia, we aimed to explore the prevailing perceptions and experiences of healthcare providers and the general public related to COVID-19 vaccines. The study applied a convergent parallel mixed-methods study design (QUAL-quant) through in-depth interviews (IDI) and a telephone survey. We completed 34 IDIs with different physician and beneficiary groups and a telephone survey with 355 primary healthcare (PHC) providers. The IDIs found that physicians held variable views on the need for COVID-19 vaccination which, combined with mixed messaging in the media landscape, fueled the public’s vaccine hesitancy. The survey results were mostly consistent with the qualitative findings as 54% of physicians hypothesized that COVID-19 vaccines were rushed without appropriate testing and 42% were concerned about the safety of those vaccines. Strategies to improve vaccination rates must target the main drivers of hesitancy, such as physicians’ poor knowledge of specific vaccines and spiraling misconceptions about them. Meanwhile, timely educational campaigns with targeted messaging for the general public should address misinformation, promote vaccine acceptance, and empower their capacity to make decisions about their health.

The social value of a PASI 90 or PASI 100 response in patients with moderate-to-severe plaque psoriasis in Spain

Introduction

Psoriasis is a chronic disease involving the skin, which significantly impacts the quality of life. Disease severity and treatment efficacy (i.e., response) are assessed through the Psoriasis Area and Severity Index (PASI). A PASI 75 response, i.e., an improvement of at least 75% with respect to the baseline PASI score, has traditionally been used as a therapeutic benchmark in clinical trials. Therapeutic advances have made PASI 90 or PASI 100 responses possible in most patients treated with some biologics. A greater response may generate social value beyond clinical outcomes that would benefit both patients and society.

Methods

A 1-year economic model was applied to estimate the impact of having a PASI 75, PASI 90, or PASI 100 response in four areas of analysis (quality of life, activities of daily living, work productivity, and out-of-pocket expenditures) and the social value of having a PASI 90 or PASI 100 response in comparison with a PASI 75 response. A mixed-methods approach based on the scientific literature, a focus group with patient, and an advisory committee with psoriasis stakeholders was used. The model included three different scenarios: having a PASI 90 vs a PASI 75 response; a PASI 100 vs a PASI 90 response; and a PASI 100 vs a PASI 75 response. A sensitivity analysis was included.

Results

The annual economic impact per patient with moderate-to-severe plaque psoriasis having a PASI 75 response was estimated at Ł 6,139, mainly related to labour productivity losses and quality of life reductions. Having a PASI 90 or a PASI 100 response would reduce this impact to €3,956 or €1,353, respectively. Accordingly, the social value of having a PASI 90 instead of a PASI 75 response was estimated at €2,183, and €4,786 with a PASI 100 response.

Discussion

A PASI 90 or PASI 100 response would have a lower economic impact and a greater social value than a PASI 75 response for patients with moderate-to-severe plaque psoriasis.

Considerations in Understanding Vaccine Effectiveness

Although vaccine effectiveness reports are essential to assessing policies on SARS-CoV-2 vaccination, several factors can affect our interpretation of the results. These include the waning of antibodies, the prevailing viral variants at the time of the study, and COVID-19 disease prevalence in the population. Disease prevalence significantly impacts absolute risk reduction and could skew expected efficacy when increased disease prevalence inflates the absolute risk reduction in the face of a constant relative risk reduction. These factors must be considered in the interpretation of vaccine effectiveness to better understand how vaccines can improve disease prevention among the population. We highlight the impact of various factors on vaccine effectiveness.

Implementing SMS reminders for routine immunization in Northern Nigeria: a qualitative evaluation using the RE-AIM framework

BACKGROUND

Short Message Service (SMS) reminders have improved vaccine uptake in low- and middle-income countries (LMICs). However, the limited use of SMS reminders in LMICs requires evaluating the intervention's internal and external validity to improve adoption and sustainability. Using the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework, we qualitatively assessed the impact of a SMS reminder intervention implemented in Kebbi State, Northwest Nigeria between May 20, 2019 and May 31, 2020. This will guide and inform future SMS reminder interventions to improve childhood immunization uptake in LMICs.

METHODS

In June 2020, we conducted 14 focus group discussions, 13 in-depth interviews, and 20 key informant interviews among 144 purposively selected participants from five local government areas of Kebbi State. For analysis, we used a deductive approach to develop preliminary codes based on the RE-AIM framework and the inductive approach to generate themes that emerged from the interviews.

RESULTS

The perceived importance and impact of the SMS reminder in improving demand and uptake for vaccinations were the consistent contributing factors that encouraged participants' participation. Other facilitators included the involvement of health workers in supporting SMS reminder registration and community gatekeepers using existing structures to convey messages on scheduled immunization services. Policymakers adopted the intervention because it aligns with the state's priority to improve immunization coverage. Similarly, the SMS reminder appealed to health workers and program managers because it reduced their workload and served as a performance monitoring tool to track immunization and intervention defaulters. Despite these, low mobile phone ownership and the inability to read text messages due to the low literacy level were the main barriers during implementation. Finally, data availability on cost-effectiveness and the intervention's impact on improving coverage was critical for scalability.

CONCLUSIONS

Our study demonstrated that SMS reminders in local languages could improve vaccination demand and uptake in resource-constrained settings due to their perceived importance and impact. Addressing the cited implementation barriers and promoting the facilitators is critical to its adoption and sustainability. Costing and impact data are needed to collaborate findings on the effectiveness of the SMS reminder to improve childhood vaccination uptake.

Trust in science, medicine and medical providers and its relations to vaccine beliefs: A latent class analysis

Aim:

People may differ in their vaccine-related beliefs (i.e. efficacy, safety, purpose), with a host of factors influencing these differences. This can produce homogeneous groups of individuals who share certain beliefs, attitudes and opinions not only towards vaccines but science and medicine in general. This study aims to characterise distinct subgroups and identify ideal targets for tailored public health interventions to reinforce favourable vaccine beliefs.

Methods:

Latent class analysis was used to derive unique profiles using the 2019 Gallup survey of 140 countries. We modelled a composite of vaccine beliefs and regressed this on class membership and relevant covariates.

Results:

Patterns of item endorsement indicated a well-fitting five-class model, with classes distinguished based on whether individuals sought personal knowledge about science, medicine and health; trusted science and scientists; and reported confidence in the health care system. The lowest levels of vaccine beliefs were reported by a class lacking trust and confidence and the highest levels were reported by a class endorsing trust, confidence and desiring medical and scientific knowledge. Country-level income was moderately related to class membership, and vaccine beliefs were higher in lower-income countries.

Conclusions:

Findings suggest that public health campaigns can focus on improving trust in science and medical providers. Efforts to improve vaccination rates can only be achieved when individuals trust science, view the work of scientists as beneficial and hold favourable views towards health care providers. Individuals will then accrue the necessary wisdom to make good health care decisions that affect not only themselves but also their fellow citizens.

The Economic and Fiscal Impact of Influenza Vaccination for Health Care Workers in Italy

Influenza has a significant impact on the health care system and also on production and economic systems. Vaccinated health care workers (HCWs) are more likely to have improved productivity compared to unvaccinated workers. The study aim was to estimate the economic and fiscal impact of an influenza vaccination program for HCWs in Italy. We performed a cost analysis aimed to estimate the indirect costs (productivity losses due to working days lost) and the increase in tax revenues derived from the increase in vaccination coverage among HCWs. Assuming an incremental increase in vaccination coverage of 10% per year over a period of 5 years, total savings could be obtained in terms of a reduction in productivity losses equal to −€4,475,497.16 and an increase in tax revenues of €327,158.84. This revenue could be used to finance other health interventions. Our results are fundamental in view of the sustainability of health systems and of a value-based allocation of health resources. Therefore, a complete social perspective, including the fiscal impact of flu vaccination, should be adopted to assess the economic value of influenza vaccines. Currently, health policies based on the whole value of flu vaccination are needed.

Influenza Vaccination Assessment according to a Value-Based Health Care Approach

Background: Seasonal influenza has a considerable public health impact, and vaccination is the key to preventing its consequences. Our aim was to describe how the value of influenza vaccination is addressed in the scientific literature considering a new value framework based on four pillars (personal, allocative, technical, and societal value). Methods: A systematic review was conducted by querying three databases. The analysis was performed on international studies focused on influenza vaccination value, and the four value pillars were taken into consideration for their description. Results: Overall, 40 studies were considered. Most of them focused on influenza vaccination in the general population (27.5%), emphasizing its value for all age groups. Most studies addressed technical value (70.4%), especially in terms of economic models and cost drivers to be considered for the economic evaluations of influenza vaccines, and societal value (63%), whereas few dealt with personal (37%) and allocative values (22.2%). Conclusions: The whole value of influenza vaccination is still not completely recognized. Knowledge and communication of the whole value of influenza vaccination is essential to guide value-based health policies. To achieve this goal, it is necessary to implement initiatives that involve all relevant stakeholders.

The value of vaccines

Optimizing vaccine spending depends on recognizing the full value of vaccination (VoV). Existing taxonomies of such value are not comprehensive because they are not guided by general theories. I rely on two such theories: subjective-value theory claims that what has value is determined by what people actually or ideally want in life. A welfarist theory of government states that a fundamental objective of government is to promote social value (or social welfare). These jointly imply that any aspect of life that individuals actually or ideally value and that could be negatively affected by vaccine-preventable diseases (and therefore positively affected by preventive vaccines) is an element of VoV. I build a more comprehensive-value taxonomy than currently exists based on this implication.

Epidemiological impact and cost-effectiveness analysis of COVID-19 vaccination in Kenya

BACKGROUND

A few studies have assessed the epidemiological impact and the cost-effectiveness of COVID-19 vaccines in settings where most of the population had been exposed to SARS-CoV-2 infection.

METHODS

We conducted a cost-effectiveness analysis of COVID-19 vaccine in Kenya from a societal perspective over a 1.5-year time frame. An age-structured transmission model assumed at least 80% of the population to have prior natural immunity when an immune escape variant was introduced. We examine the effect of slow (18 months) or rapid (6 months) vaccine roll-out with vaccine coverage of 30%, 50% or 70% of the adult (>18 years) population prioritising roll-out in those over 50-years (80% uptake in all scenarios). Cost data were obtained from primary analyses. We assumed vaccine procurement at US$7 per dose and vaccine delivery costs of US$3.90-US$6.11 per dose. The cost-effectiveness threshold was US$919.11.

FINDINGS

Slow roll-out at 30% coverage largely targets those over 50 years and resulted in 54% fewer deaths (8132 (7914-8373)) than no vaccination and was cost saving (incremental cost-effectiveness ratio, ICER=US$-1343 (US$-1345 to US$-1341) per disability-adjusted life-year, DALY averted). Increasing coverage to 50% and 70%, further reduced deaths by 12% (810 (757-872) and 5% (282 (251-317) but was not cost-effective, using Kenya's cost-effectiveness threshold (US$919.11). Rapid roll-out with 30% coverage averted 63% more deaths and was more cost-saving (ICER=US$-1607 (US$-1609 to US$-1604) per DALY averted) compared with slow roll-out at the same coverage level, but 50% and 70% coverage scenarios were not cost-effective.

INTERPRETATION

With prior exposure partially protecting much of the Kenyan population, vaccination of young adults may no longer be cost-effective.

Capturing the value of vaccination within health technology assessment and health economics: Literature review and novel conceptual framework

BACKGROUND

Vaccination provides significant health gains to individuals and society and can potentially improve health equity, healthcare systems and national economies. Policy decisions, however, are rarely informed by comprehensive economic evaluations (EE) including vaccination's wide-ranging value. The objective of this analysis was to focus on health technology assessment systems to identify relevant value concepts in order to improve current EE of non-pandemic vaccines.

METHODS

Following a literature review, a novel Value of Vaccination (VoV) framework was developed with experts in vaccine EE from developed countries with established health technology assessment systems.

RESULTS

Forty-four studies presenting value frameworks or concepts applicable to vaccination were included. Eighteen unique value concepts relevant to EE were identified and defined. These were categorised within the VoV framework using three dimensions, moving from a narrow payer perspective to a more expansive and societal perspective. The dimensions were: (I) conventional payer perspective concepts (e.g., health gains in vaccinees, direct medical costs); (II) conventional societal perspective concepts (e.g., indirect health/economic gains to caregivers/households, productivity in vaccinees); and (III) novel societal concepts (e.g., financial risk protection, peace of mind, societal health gains, healthcare systems security, political stability, social equity and macroeconomic gains). While good quality evidence and methods are available to support concepts in Dimensions I and II, further work is needed to generate the required evidence for vaccination impact on Dimension III concepts.

CONCLUSIONS

The devastating effect on nations of the COVID-19 pandemic has helped to highlight the potential far-reaching benefits that many vaccination programmes can offer. This VoV framework is particularly relevant to policy decisions considering EE, and the potential future expansion of non-pandemic vaccination value considerations. The framework helps to understand and compare current value considerations across countries and payer versus societal perspectives. It provides decision-makers with a transparent and logical path to broaden consideration of VoV in EE.

COVID-19 Vaccination Campaign among the Health Workers of Fondazione Policlinico Universitario Agostino Gemelli IRCCS: A Cost–Benefit Analysis

Vaccinations generate health, economic and social benefits in both vaccinated and unvaccinated populations. The aim of this study was to conduct a cost–benefit analysis to estimate the costs and benefits associated with the COVID-19 vaccination campaign for health workers in Fondazione Policlinico Universitario Agostino Gemelli IRCCS (FPG). The analysis included 5152 healthcare workers who voluntarily received the Pfizer–BioNTech COVID-19 vaccine, divided into physicians, nurses and other health workers. Data about vaccine cost, administration and materials were derived from administrative databases of the FPG from 28 December 2020 to 31 March 2021. The costs associated with the COVID-19 vaccination campaign amounted to EUR 2,221,768, while the benefits equaled EUR 10,345,847. The benefit-to-cost ratio resulted in EUR 4.66, while the societal return on investment showed a ratio of EUR 3.66. The COVID-19 vaccination campaign for health workers in FPG has high social returns and it strengthens the need to inform and update decision-making about the economic and social benefits associated with a vaccination campaign. Health economic evaluations on vaccines should always be considered by decision-makers when considering the inclusion of a new vaccine into the national program.

Capturing the value of vaccination within health technology assessment and health economics: Country analysis and priority value concepts

BACKGROUND

A value of vaccination framework for economic evaluation (EE) identified unique value concepts for the broad benefits vaccination provides to individuals, society, healthcare systems and national economies. The objectives of this paper were to work with experts in developed countries to objectively identify three priority concepts to extend current EE.

METHODS

The previously developed classification of value concepts in vaccination distinguished 18 concepts, categorised as conventional payer and societal perspective concepts and novel broader societal concepts. Their inclusion in current EE guidelines was assessed. Experts identified eight criteria relevant to decision-making and measurement feasibility, which were weighted and used to score each concept. The relative ranking of concepts by importance and the gaps in guidelines were used to identify three priority concepts on which to focus immediate efforts to extend EE.

RESULTS

The EE guidelines review highlighted differences across countries and between guidelines and practice. Conventional payer perspective concepts (e.g., individual and societal health gains and medical costs) were generally included, while gaps were evident for conventional societal perspective concepts (e.g., family/caregiver health and economic gains). Few novel broader societal benefits were considered, and only in ad hoc cases. The top-three concepts for near-term consideration: macroeconomic gains (e.g., benefiting the economy, tourism), social equity and ethics (e.g., equal distribution of health outcomes, reduced health/financial equity gaps) and health systems strengthening, resilience and security (e.g., efficiency gains, reduced disruption, increased capacity).

CONCLUSIONS

Gaps, inconsistencies and limited assessment of vaccination value in EE can lead to differences in policy and vaccination access. The three priority concepts identified provide a feasible approach for capturing VoV more broadly in the near-term. Robust methods for measuring and valuing these concepts in future assessments will help strengthen the evidence used to inform decisions, improving access to vaccines that are demonstrably good value for money from society's point of view.

Missed Opportunities for Vaccination and Associated Factors among Children Attending Primary Health Care Facilities in Cape Town, South Africa: A Pre-Intervention Multilevel Analysis

Despite the substantial efforts at ensuring universal access to routine immunisation services among children in South Africa, major gaps in immunisation coverage remain. This study assessed the magnitude of missed opportunities for vaccination (MOV) and associated factors among children aged 0–23 months attending primary health care (PHC) facilities in Cape Town. We used multilevel binomial logistic regression models to explore individual and contextual factors associated with MOV, with children aged 0–23 months at Level 1, nested within PHC facilities (Level 2). A total of 674 children and their caregivers were enrolled. MOV prevalence was 14.1%, ranging from 9.1% to 18.9% across sub-districts. Dose-specific MOV prevalence was highest for the second dose of measles vaccine (9.5%) and lowest for the first dose of rotavirus vaccine (0.6%). The likelihood of a child experiencing MOV was significantly associated with caregivers’ low level of education (Odds ratio (OR) = 3.53, 95% credible interval (CrI): 1.13–11.03), recent receipt of immunisation messages (OR = 0.46, 95%CrI: 0.25–0.87), shared immunisation decision making by both parents (OR = 0.21, 95%CrI: 0.07–0.62) and health facility staff number (OR = 0.18, 95%CrI: 0.06–0.61). The burden of MOV among children in Cape Town is influenced by individual and contextual factors, which provide important opportunities for quality improvement and broader strategies to improve routine immunisation service delivery.

COVID-19 provides an opportunity to build a resilient and equitable immunization delivery system

The COVID-19 pandemic has weakened the health systems in many countries particularly putting at risk efforts on the Immunization Agenda to make vaccination available to everyone, everywhere, by 2030. Immunization Agenda 2030 reconfirms the importance of reducing the absolute number of zero-dose children and increasing the proportion of children who complete their vaccinations on time. Despite the gains in promoting equity in immunization services, many children missed vaccination because of the COVID-19 pandemic that disrupted well planned strategies. The cancellation of outreach services following the COVID-19-motivated lockdown meant many children missed vaccination. The situation was further worsened by vaccination related rumors and fears. The collapse of the Primary Health Care (PHC) service provision during the epidemic may lead to higher under-five mortality similar to the Ebola Virus Disease epidemic in West Africa. The post COVID-19 recovery strategy should include strengthening the service delivery systems to remain resilient when threatened by emergencies. The recovery must therefore focus on rebuilding trust as the foundation for vaccine acceptance and demand which can only be achieved by appropriate community engagement.

Protecting the herd with vaccination

How much do COVID-19 vaccines reduce transmission? The answer is a moving target.

PCV13 Vaccination of Adults against Pneumococcal Disease: What We Have Learned from the Community-Acquired Pneumonia Immunization Trial in Adults (CAPiTA)

The Community-Acquired Pneumonia immunization Trial in Adults (CAPiTA) evaluated older adult pneumococcal vaccination and was one of the largest vaccine clinical trials ever conducted. Among older adults aged ≥65 years, the trial established 13-valent pneumococcal conjugate vaccine (PCV13) efficacy in preventing first episodes of bacteremic and nonbacteremic pneumococcal vaccine serotype (VT) community acquired pneumonia (CAP), and of vaccine serotype invasive pneumococcal disease (VT-IPD). Since the publication of the original trial results, 15 additional publications have extended the analyses. In this review, we summarize and integrate the full body of evidence generated by these studies, contextualize the results in light of their public health relevance, and discuss their implications for the assessment of current and future adult pneumococcal vaccination. This accumulating evidence has helped to better understand PCV13 efficacy, serotype-specific efficacy, efficacy in subgroups, the interpretation of immunogenicity data, and the public health value of adult PCV vaccination.

An Empirical Analysis of Income Elasticity of Out-of-Pocket Healthcare Expenditure in Mauritius

A free universal healthcare provision exists in Mauritius. Yet the share of out-of-pocket healthcare expenditure out of total household expenditure has been growing over time. This study estimates income elasticity of out-of-pocket healthcare expenditure using Mauritian household data within an Engel curve framework. In the absence of longitudinal data on out-of-pocket healthcare expenditure patterns, the study proposes the application of the pseudo-panel approach using cross-sectional Household Budget Survey waves from 1996/97 to 2017. Income elasticity of out-of-pocket healthcare expenditure is estimated to be 0.938, which is just below unity. This implies that out-of-pocket healthcare demand is not considered to be a luxury, but a necessity in Mauritius. In order to see the differences in income elasticities by income groups, separate regressions are estimated for each income quartile over different years. The results indicate that income elasticities of out-of-pocket healthcare expenditure vary non-monotonically.

Bereitschaft zur Impfung mit einem COVID‑19-Vakzin – Risikoeinschätzung, Impferfahrungen und Einstellung zu Behandlungsverfahren

Hintergrund

Impfungen stellen eine bedeutende Präventionsmaßnahme dar. Grundlegend für die Eindämmung der Coronapandemie mittels Durchimpfung der Gesellschaft ist eine ausgeprägte Impfbereitschaft.

Ziel der Arbeit

Die Impfbereitschaft mit einem COVID‑19-Vakzin (Impfstoff gegen das Coronavirus) und deren Einflussfaktoren werden anhand einer Zufallsstichprobe der Gesamtbevölkerung in Deutschland untersucht.

Material und Methoden

Die Studie basiert auf einer telefonischen Zufallsstichprobe und berücksichtigt ältere und vorerkrankte Personen ihrem Bevölkerungsanteil entsprechend. Die Ein-Themen-Bevölkerungsbefragung zur Impfbereitschaft (n = 2014) wurde im November/Dezember 2020 durchgeführt.

Ergebnisse

Die Impfbereitschaft in der Stichprobe liegt bei rund 67 %. Vorerfahrungen mit Impfungen moderieren die Impfbereitschaft. Sie steigt bei Zugehörigkeit zu einer Risikogruppe. Der Glaube an die Wirksamkeit alternativer Heilmethoden und Befürwortung alternativer Behandlungsverfahren geht mit geringerer Impfbereitschaft einher. Ältere Menschen sind impfbereiter, kovariierend mit ihrer Einschätzung höherer Gefährdung bei Erkrankung. Ebenso ist die Ablehnung einer Impfung mit der Überschätzung von Nebenwirkungen assoziiert.

Schlussfolgerung

Die Impfbereitschaft hängt mit Impferfahrungen und Einstellungen zu Gesundheitsbehandlungsverfahren allgemein zusammen. Die Überschätzung der Häufigkeit ernsthafter Nebenwirkungen bei Impfungen weist auf weit verbreitete Fehlinformationen hin.

Considerations for estimating real-world outcomes and value in vaccination: A case study with adult hepatitis B virus vaccination

BACKGROUND

In the absence of field efficacy studies, estimating the real-world effectiveness of vaccines may consider immunogenicity from randomized controlled clinical trials and real-world adherence. Combining seroprotection rates (SPRs) with regimen completion rates gives an estimate of an effective vaccine protection rate (eVPR), which can be leveraged to evaluate real-world cost-effectiveness by linking it with vaccine costs to estimate the cost-per-protected patient (CPP).

METHODS

This study evaluated eVPR and CPP as estimates of vaccine clinical- and cost-effectiveness of two-dose (HepB-CpG) and three-dose (HepB-Alum) hepatitis B virus (HBV) vaccines in the general adult population and a subpopulation with diabetes mellitus. eVPR was calculated from head-to-head SPR data from phase 3 clinical trials directly comparing HepB-CpG and HepB-Alum vaccine regimens and real-world head-to-head adherence data. CPP was calculated as the average cost of each regimen divided by eVPR.

RESULTS

Higher eVPR in the adult population was achieved with HepB-CpG (68.0%) versus HepB-Alum (41.6%), reflecting the combination of higher SPR and vaccine regimen completion. The CPP for HepB-CpG ($331.31) was $45.67 (95% CI: $36.66, $55.19) less than HepB-Alum ($377.09). Greater savings were observed among persons with diabetes, with CPP $149.60 (95% CI: $80.29, $195.63) lower with HepB-CpG ($367.57) than HepB-Alum ($517.37).

CONCLUSIONS

Metrics estimating vaccine real-world effectiveness and value may guide informed decisions in vaccine selection. For example, using eVPR and CPP, HepB-CpG represents a more effective, value-advantaged approach than HepB-Alum toward reducing HBV infection.

Benefit-Risk Assessment of Vaccines. Part I: A Systematic Review to Identify and Describe Studies About Quantitative Benefit-Risk Models Applied to Vaccines

Introduction

Understanding the balance between the benefits and risks of vaccination is essential to ensure informed and adequate public health decision making. Quantitative benefit–risk models (qBRm) represent useful tools to help decision makers with supporting benefit–risk assessment throughout the lifecycle of a medical product. However, few initiatives have been launched to harmonise qBRm approaches, specifically for vaccines.

Objectives

The aim of this paper was to identify publications about qBRm applied to vaccines through a systematic literature review, and to describe their characteristics.

Methods

Medline, Scopus and Institute for Scientific Information Web of Knowledge databases were searched to identify articles in English, published from database inceptions up to December 2019. The search strategy included the combination of three key concepts: ‘benefit–risk’, ‘modelling’ and ‘vaccines’. Data extracted included the modelling context and the methodological approaches used.

Results

Of 3172 publications screened, 48 original publications were included. Most of the selected studies were published over the past decade and focused on rotavirus (15), dengue (10) and influenza (6) vaccines. The majority (30) of studies reported analyses related to high-income countries. The methodology of the studies differed, particularly in modelling techniques, benefit–risk measures, and sensitivity analyses. The present work also pointed out a high level of variability in the quality of reporting across studies, with particular regard to input parameters and methodological approaches.

Conclusions

This review provides an extensive list of qBRm applied to vaccines. Discrepancies across studies were identified during our review. While the number of published qBRm studies is increasing, no reporting guidance for qBRm applied to vaccines is currently available. This may affect decision makers’ confidence in the results and their benefit–risk assessment(s); therefore, the development of such reporting guidance is highly needed.

Electronic supplementary material

The online version of this article (10.1007/s40264-020-00984-7) contains supplementary material, which is available to authorized users.

Ensuring sustainability of polio immunization in health system transition: lessons from the polio eradication initiative in Indonesia

BACKGROUND

Sustaining an effective evidence-based health intervention will maximize its impact on public health. Political and governmental reforms impacted on immunization program sustainability both positively and negatively. This study aims to explore the sustainability of polio immunization in a decentralized health system taking lessons learned from a polio eradication initiative in Indonesia.

METHODS

We collected qualitative data through in-depth interviews with 27 key informants from various backgrounds at district, provincial, and national levels, consisting of frontline workers, managers, and Non-government Organizations (NGOs). We conducted thematic analysis and triangulated using document reviews. We also conducted member checking and peer debriefing to ensure trustworthiness.

RESULTS

Competing priority was identified as the significant challenge to sustain government commitment for polio immunization and AFP surveillance during the transition toward a decentralized health system. Variation of local government capacities has also affected immunization delivery and commitment at the sub-national level government. The government reform has led to a more democratic society, facilitating vaccine rejection and hesitancy. The multi-sector partnership played a significant role in maintaining polio immunization coverage. Strong and continuous advocacy and campaign were essential to raising awareness of the community and policymakers to keep polio in the agenda and to maintain the high polio immunization coverage.

CONCLUSION

Competing priority was the major factor affecting high polio immunization coverage during the decentralization transition. Strong advocacy is needed at every level, from district to national level, to keep polio immunization prioritized.

Shell-mediated phagocytosis to reshape viral-vectored vaccine-induced immunity

Adenovirus (Ad) has been extensively developed as a gene delivery vector, but the potential side effect caused by systematic immunization remains one major obstacle for its clinical application. Needle-free mucosal immunization with Ad-based vaccine shows advantages but still faces poor mucosal responses. We herein report that the chemical engineering of single live viral-based vaccine effectively modulated the location and pattern of the subsequently elicited immunity. Through precisely assembly of functional materials onto single live Ad particle, the modified virus entered host cell in a phagocytosis-dependent manner, which is completely distinct from the receptor-mediated entry of native Ad. RNA-Seq data further demonstrated that the modified Ad-induced innate immunity was sharply reshaped via phagocytosis-related pathway, therefore promoting the activation and mature of antigen presentation cells (APC). Moreover, the functional shell enabled the modified Ad-based vector with enhanced muco-adhesion to nasal tissues in mice, and then prolonged resident time onto mucosal surface, leading to the robust mucosal IgA production and T cell immunity at local and even remote mucosal-associated lymphoid tissues. This study demonstrated that vaccine-induced immunity can be well modulated by chemistry engineering, and this method provides the rational design for needle-free mucosa-targeting vaccine against a variety of emerging infectious diseases.

The CAPACITI Decision-Support Tool for National Immunization Programs

OBJECTIVES

Immunization programs in low-income and middle-income countries (LMICs) are faced with an ever-growing number of vaccines of public health importance recommended by the World Health Organization, while also financing a greater proportion of the program through domestic resources. More than ever, national immunization programs must be equipped to contextualize global guidance and make choices that are best suited to their setting. The CAPACITI decision-support tool has been developed in collaboration with national immunization program decision makers in LMICs to structure and document an evidence-based, context-specific process for prioritizing or selecting among multiple vaccination products, services, or strategies.

METHODS

The CAPACITI decision-support tool is based on multi-criteria decision analysis, as a structured way to incorporate multiple sources of evidence and stakeholder perspectives. The tool has been developed iteratively in consultation with 12 countries across Africa, Asia, and the Americas.

RESULTS

The tool is flexible to existing country processes and can follow any type of multi-criteria decision analysis or a hybrid approach. It is structured into 5 sections: decision question, criteria for decision making, evidence assessment, appraisal, and recommendation. The Excel-based tool guides the user through the steps and document discussions in a transparent manner, with an emphasis on stakeholder engagement and country ownership.

CONCLUSIONS

Pilot countries valued the CAPACITI decision-support tool as a means to consider multiple criteria and stakeholder perspectives and to evaluate trade-offs and the impact of data quality. With use, it is expected that LMICs will tailor steps to their context and streamline the tool for decision making.

COVID-19 and the Gaping Wounds of South Africa's Suboptimal Immunisation Coverage: An Implementation Research Imperative for Assessing and Addressing Missed Opportunities for Vaccination

Despite South Africa's substantial investments in and efforts at ensuring universal access to immunisation services, progress has stalled and remains suboptimal across provinces and districts. An additional challenge is posed by the ongoing coronavirus disease 2019 (COVID-19) pandemic, which has disrupted immunisation services globally, including in South Africa. While there is growing evidence that missed opportunities for vaccination (MOV) are a major contributor to suboptimal immunisation progress globally, not much is known about the burden and determinants of MOV in the South African context. Herein, we make a case for assessing MOV as a strategy to address current immunisation coverage gaps while mitigating the adverse impacts of the COVID-19 pandemic on immunisation services. We illustrate a practical implementation research approach to assessing the burden of MOV among children in primary care settings; for understanding the factors associated with MOV; and for designing, implementing, and evaluating context-appropriate quality improvement interventions for addressing missed opportunities. Such efforts are vital for building health system resilience and maintaining immunisation programme capacity to optimally deliver essential health services such as routine childhood immunisation, even during pandemics.

The Economic Burden of Influenza-Like Illness among Children, Chronic Disease Patients, and the Elderly in China: A National Cross-Sectional Survey

Background: The disease burden of seasonal influenza is substantial in China, while there is still a lack of nationwide economic burden estimates. This study aims to examine influenza-like illness (ILI) prevalence, healthcare-seeking behaviors, economic impact of ILI, and its influencing factors among three priority groups during the 2018–19 influenza season. Methods: From August to October 2019, 6668 children’s caregivers, 1735 chronic disease patients, and 3849 elderly people were recruited from 10 provinces in China to participate in an on-site survey. The economic burden of ILI consisted of direct (medical or non-medical) and indirect burdens, and a two-part model was adopted to predict the influencing factors of total economic burden. Results: There were 45.73% children, 16.77% chronic disease patients, and 12.70% elderly people reporting ILI, and most participants chose outpatient service or over-the-counter (OTC) medication after ILI. The average economic burden was CNY 1647 (USD 237.2) for children, CNY 951 (USD 136.9) for chronic disease patients, and CNY 1796 (USD 258.6) for the elderly. Two-part regression showed that age, gender, whether the only child in the family, region, and household income were important predictors of ILI economic burden among children, while age, region, place of residence, basic health insurance, and household income were significant predictors of ILI economic burden among chronic disease patients and the elderly. Conclusions: A large economic burden of ILI was highlighted, especially among the elderly with less income and larger medical burdens, as well as children, with higher prevalence and higher self-payment ratio. It is important to adopt targeted interventions for high-risk groups, and this study can help national-level decision-making on the introduction of influenza vaccination as a public health project.

Impact and effectiveness of a conjugate vaccine against invasive pneumococcal disease in Finland - a modelling approach

The evaluation of the public health impact of a vaccination program is essential in monitoring its policy relevance. Vaccine impact (VI) is usually assessed in a before-after design, in which data on disease burden without vaccination program is required from a historical reference period. It takes into account the indirect effects and therefore aims to describe the public health performance of the vaccination program in the population. Vaccine effectiveness (VE), measured in parallel settings, quantifies the benefit for an individual of being vaccinated but does not address the indirect effects of a vaccination program. The motivation of this paper is to gain insight into patterns of how VI and VE have manifested under large-scale use of a ten-valent pneumococcal conjugate vaccine in Finnish children. We construct a simple pseudo-dynamic model that mimics typical post-vaccination trends in the incidences of pneumococcal carriage and invasive disease in children when the proportion of vaccine-type carriage decreases. In the context of the model, we define the parameters of interest for VI and VE and explore how their expected values evolve over time. For comparison, we demonstrate the application of VI and VE estimation by using register data.

The impact of two-dose varicella vaccination on varicella and herpes zoster incidence in South Korea using a mathematical model with changing population demographics

BACKGROUND

In South Korea, one-dose varicella vaccination was introduced to the National Immunization Program in 2005, but varicella outbreaks have continued to occur. Therefore, a two-dose vaccination strategy is considered.

METHODS

We developed an age-structured deterministic compartment model using Korean population projection data. The impact of adding a second dose of varicella vaccine on varicella and herpes zoster (HZ) epidemiology was assessed under four different vaccine effectiveness (VE) scenarios (base, moderate, lowest, highest) and the optimal timing of the second vaccine dose (18 months, 4, 5, or 6 years of age) was examined over the period 2020-2065.

RESULTS

A two-dose vaccination schedule reduced the cumulative varicella incidence by > 90% compared to no vaccination, regardless of the VE. The additional reduction attributable to a second dose compared to a single dose was greatest (82%) with the lowest VE scenario. A second dose at 6 years of age reduced the varicella incidence at a population level, whereas a second dose at 18 months of age reduced the varicella incidence primarily in the target birth cohorts. Routine vaccination at the age of 18 months with a catch-up vaccination of 6-year-olds was the optimal strategy for birth cohort and population-level control. HZ incidence continued to increase under no vaccination scenario, which represents the effect of aging population. Under a two-dose scenario, the additional increase in HZ incidence attributable to the reduced exogenous boosting was small relative to a one-dose scenario and a further reduction in HZ cases was observed.

CONCLUSION

A two-dose varicella vaccination schedule would significantly reduce varicella and HZ incidence in the long term. A second dose at the age of 18 months with a catch-up vaccination of 6-year-olds would be optimal for controlling varicella in South Korea.

Operation Warp Speed: implications for global vaccine security

Several global efforts are underway to develop COVID-19 vaccines, and interim analyses from phase 3 clinical testing have been announced by nine organisations: Pfizer, the Gamaleya Research Institute of Epidemiology and Microbiology, Moderna, AstraZeneca, Sinopharm Group, Sinovac Biotech, Johnson & Johnson, Novavax, and CanSino Biologics. The US programme known as Operation Warp Speed provided US$18 billion in funding for development of vaccines that were intended for US populations. Depending on safety and efficacy, vaccines can become available through mechanisms for emergency use, expanded access with informed consent, or full licensure. An important question is: how will these Operation Warp Speed vaccines be used for COVID-19 prevention in global health settings? We address some key questions that arise in the transition from US to global vaccine prevention efforts and from ethical and logistical issues to those that are relevant to global vaccine security, justice, equity, and diplomacy.

Looking beyond COVID-19 vaccine phase 3 trials

After the recent announcement of COVID-19 vaccine efficacy in clinical trials by several manufacturers for protection against severe disease, a comprehensive post-efficacy strategy for the next steps to ensure vaccination of the global population is now required. These considerations should include how to manufacture billions of doses of high-quality vaccines, support for vaccine purchase, coordination of supply, the equitable distribution of vaccines and the logistics of global vaccine delivery, all of which are a prelude to a massive vaccination campaign targeting people of all ages. Furthermore, additional scientific questions about the vaccines remain that should be answered to improve vaccine efficacy, including questions regarding the optimization of vaccination regimens, booster doses, the correlates of protection, vaccine effectiveness, safety and enhanced surveillance. The timely and coordinated execution of these post-efficacy tasks will bring the pandemic to an effective, and efficient, close.

Willingness to Pay for Seasonal Influenza Vaccination among Children, Chronic Disease Patients, and the Elderly in China: A National Cross-Sectional Survey

Background: The disease burden of seasonal influenza is substantial in China, while the vaccination rate is extremely low, and most people have to pay 100% for vaccination. This study aims to examine willingness to pay (WTP) and recommended financing sources for influenza vaccination among children, chronic disease patients, and the elderly in China and determine feasible measures to expand vaccination coverage. Methods: From August to October 2019, 6668 children's caregivers, 1735 chronic disease patients, and 3849 elderly people were recruited from 10 provinces in China. An on-site survey was conducted via a especially designed PAD system. Tobit regression was adopted to predict the influencing factors of WTP. Results: The average WTP was 127.5 yuan (USD18.0) for children, 96.5 yuan (USD13.7) for chronic disease patients, and 88.1 yuan (USD12.5) for the elderly. Most participants in the three groups thought government subsidies (94.8%, 95.8%, and 95.5%) or health insurance (94.3%, 95.3%, and 94.5%) should cover part of the cost, and nearly four-fifths (80.1%, 79.5%, and 76.8%) believed that individuals should also pay for part. Tobit regression showed that a higher perceived importance of vaccination, knowing about priority groups, and considering that individuals should co-pay were promoters of WTP, while considering price as a hindrance lowered WTP. Conclusions: The WTP for influenza vaccination among children, chronic disease patients, and the elderly in China is fairly high, suggesting that price is not the primary hindrance and there is room to expand immunization. Most participants expected the government and/or health insurance to pay part of the cost, and such supportive funding could act as a promotive policy "signal" to improve vaccine uptake. Influenza-related health education is also needed to expand vaccine coverage.

Impact of Vaccines; Health, Economic and Social Perspectives

In the 20th century, the development, licensing and implementation of vaccines as part of large, systematic immunization programs started to address health inequities that existed globally. However, at the time of writing, access to vaccines that prevent life-threatening infectious diseases remains unequal to all infants, children and adults in the world. This is a problem that many individuals and agencies are working hard to address globally. As clinicians and biomedical scientists we often focus on the health benefits that vaccines provide, in the prevention of ill-health and death from infectious pathogens. Here we discuss the health, economic and social benefits of vaccines that have been identified and studied in recent years, impacting all regions and all age groups. After learning of the emergence of SARS-CoV-2 virus in December 2019, and its potential for global dissemination to cause COVID-19 disease was realized, there was an urgent need to develop vaccines at an unprecedented rate and scale. As we appreciate and quantify the health, economic and social benefits of vaccines and immunization programs to individuals and society, we should endeavor to communicate this to the public and policy makers, for the benefit of endemic, epidemic, and pandemic diseases.

Where and when to vaccinate? Interdisciplinary design and evaluation of the 2018 Tanzanian anti-rabies campaign

OBJECTIVES

Hoping to improve health-related effectiveness, a two-phase vaccination against rabies was designed and executed in northern Tanzania in 2018, which included geo-epidemiological and economic perspectives.

METHODS

Considering the local bio-geography and attempting to rapidly establish a protective ring around a city at risk, the first phase intervened on sites surrounding that city, where the population density was lower than in the city at risk. The second phase vaccinated a rural area.

RESULTS

No rabies-related case has been reported in the vaccinated areas for over a year post-immunisation; hence, the campaign is viewed as highly cost-effective. Other metrics included: rapid implementation (concluded in half the time spent on other campaigns) and the estimated cost per protected life, which was 3.28 times lower than in similar vaccinations.

CONCLUSIONS

The adopted design emphasised local bio-geographical dynamics: it prevented the occurrence of an epidemic in a city with a higher demographic density than its surrounding area and it also achieved greater effectiveness than average interventions. These interdisciplinary, policy-oriented experiences have broad and immediate applications in settings of limited and/or time-sensitive (expertise, personnel, and time available to intervene) resources and conditions.

A Vaccine Against Group B Streptococcus: Recent Advances

Group B streptococcus (GBS) causes a high burden of neonatal and infant disease globally. Implementing a vaccine for pregnant women is a promising strategy to prevent neonatal and infant GBS disease and has been identified as a priority by the World Health Organisation (WHO). GBS serotype-specific polysaccharide – protein conjugate vaccines are at advanced stages of development, but a large number of participants would be required to undertake Phase III clinical efficacy trials. Efforts are therefore currently focused on establishing serocorrelates of protection in natural immunity studies as an alternative pathway for licensure of a GBS vaccine, followed by Phase IV studies to evaluate safety and effectiveness. Protein vaccines are in earlier stages of development but are highly promising as they might confer protection irrespective of serotype. Further epidemiological, immunological and health economic studies are required to enable the vaccine to reach its target population as soon as possible.

Commentary: Why Has Uptake of Pneumococcal Vaccines for Children Been So Slow? The Perils of Undervaluation

Pediatric pneumococcal disease exacts a substantial burden on global health, much of which is vaccine-preventable. Despite this considerable burden and the demonstrably high efficacy of pneumococcal conjugate vaccines (PCVs), the overall level of PCV uptake remains concerningly low, especially compared with that of other childhood-recommended vaccines, such as tuberculosis and polio. A broad set of plausible explanations exists for this low uptake, including logistical challenges, psychosocial factors and affordability. One additional and systematic cause of low uptake, which is the focus of our discussion, is economists' and policymakers' tendency to undervalue vaccination in general by adopting a narrow health sector perspective when performing economic evaluations of vaccines. We present an alternative, societal framework for economic evaluations that encompasses a broader set of socioeconomic benefits in addition to health benefits. Quantifying a more comprehensive taxonomy of PCV's benefits will help to address potential undervaluation and may be sufficient not only to justify recommendation and reimbursement but also to stimulate efforts and investment toward closing coverage gaps.

How to assess for the full economic value of vaccines? From past to present, drawing lessons for the future

Background:Cost-effectiveness analysis (CEA) is the economic analysis method most commonly applied today in the context of replacing one treatment with a new one in a developed healthcare system to improve efficiency. CEA is often requested by local healthcare decision-makers to grant reimbursement. New preventative interventions, such as new vaccines, may however have much wider benefits inside and outside healthcare, when compared with treatment. These additional benefits include externalities on indirect clinical impact, reallocation of specific healthcare resources, improved quality of care, better productivity, better disease control, better fiscal revenues, and others. But these effects are sometimes difficult to integrate into a meaningful CEA result. They may appear as specific benefits for specific stakeholders, other than the stakeholders in healthcare. Objective: Based on a historical view about the application of economic assessments for vaccines our objective has been to make the inventory of who was/is interested in knowing the economic value of vaccines, in what those different stakeholders are likely to see the benefit from their perspective and how  were/are we able to measure those benefits and to report them well. Results: The historical view disclosed a limited interest in the economic assessment of vaccines at start, more than 50 years ago, that was comparable to the assessment of looking for more efficiency in new industries through optimization exercises. Today, we are exposed to a very rich panoply of different stakeholders (n= 16). They have their specific interest in many different facets of the vaccine benefit of which some are well known in the conventional economic analysis (n=9), but most outcomes are hidden and not enough evaluated and reported (n=26). Meanwhile we discovered that many different methods of evaluation have been explored to facilitate the measurement and reporting of the benefits (n=18). Conclusion: Our recommendation for future economic evaluations of new vaccines is therefore to find the right combination among the three entities of stakeholder type selection, outcome measure of interest for each stakeholder, and the right method to apply. We present at the end examples that illustrate how successful this approach can be.

Immunization: vital progress, unfinished agenda

Vaccination against infectious diseases has changed the future of the human species, saving millions of lives every year, both children and adults, and providing major benefits to society as a whole. Here we show, however, that national and sub-national coverage of vaccination varies greatly and major unmet needs persist. Although scientific progress opens exciting perspectives in terms of new vaccines, the pathway from discovery to sustainable implementation can be long and difficult, from the financing, development and licensing to programme implementation and public acceptance. Immunization is one of the best investments in health and should remain a priority for research, industry, public health and society.

Can Complementary Prime-Boost Immunization Strategies Be an Alternative and Promising Vaccine Approach Against Dengue Virus?

Dengue is one of the most important diseases transmitted by mosquitoes. Dengvaxia®, a vaccine registered in several countries, cannot be administered to non-immune individuals and children younger than 9 years old, due to safety reasons. There are two vaccine candidates in phase 3 efficacy trials, but their registration date is completely unknown at this moment. So, the development of new vaccines or vaccine strategies continues to be a priority for the WHO. This work reviews some complementary prime-boost immunization studies against important human pathogens. Additionally, it reviews the results obtained using this regimen of immunization against dengue virus as a potential alternative approach for finding a safe and efficient vaccine. Finally, the main elements associated with this strategy are also discussed. The generation of new strategies of vaccination against dengue virus, must be directed to reduce the risk of increasing viral load through sub-neutralizing antibodies and it must be also directed to induce a polyfunctional T cell response. Complementary prime-boost immunization strategies could emerge as an interesting approach to induce solid immunity or at least to reduce viral load after natural infection, avoiding severe dengue. Subunit vaccine could be safe and attractive antigens for this strategy, especially proteins including B, and T-cells epitopes for inducing humoral and cellular immune responses, which can play an important role controlling the disease.

Drug Resistance and the Prevention Strategies in Food Borne Bacteria: An Update Review

Antibiotic therapy is among the most important treatments against infectious diseases and has tremendously improved effects on public health. Nowadays, development in using this treatment has led us to the emergence and enhancement of drug-resistant pathogens which can result in some problems including treatment failure, increased mortality as well as treatment costs, reduced infection control efficiency, and spread of resistant pathogens from hospital to community. Therefore, many researches have tried to find new alternative approaches to control and prevent this problem. This study, has been revealed some possible and effective approaches such as using farming practice, natural antibiotics, nano-antibiotics, lactic acid bacteria, bacteriocin, cyclopeptid, bacteriophage, synthetic biology and predatory bacteria as alternatives for traditional antibiotics to prevent or reduce the emergence of drug resistant bacteria.

Reply letter: trends in varicella and herpes zoster epidemiology before and after the implementation of universal one-dose varicella vaccination over one decade in South Korea, 2003-2015

In the letter, Lai SW suggested that the cost-benefit of two-dose varicella vaccines should be considered since universal one-dose vaccination effectively reduced varicella incidence in Taiwan. However, the vaccination impact was different between South Korea and Taiwan. In South Korea, only a moderate reduction in varicella incidence was observed after implementing universal one-dose vaccination. Such difference possibly reflects the relatively high background varicella incidence in South Korea. As substantial variability in varicella epidemiology exists across countries, an optimal vaccination strategy may differ in each country. Despite the effectiveness of one-dose vaccine being moderate, primary vaccine failure and rapidly waning immunity are major concerns. Therefore, two-dose vaccination would be a reasonable choice for effectively preventing virus transmission in South Korea.

The Connection between the Averted Infections Ratio and the Rate Ratio in Active-control Trials of Pre-exposure Prophylaxis Agents

The design and analysis of active-control trials to evaluate experimental HIV pre-exposure prophylaxis (PrEP) agents pose serious statistical challenges. We recently proposed a new outcome measure, the averted infections ratio (AIR) – the proportion of infections that would be averted by using the experimental agent rather than the control agent (compared to no intervention). The main aim of the current paper is to examine the mathematical connection between AIR and the HIV incidence rate ratio, the standard outcome measure. We also consider the sample size implications of the choice of primary outcome measure and explore the connection between effectiveness and efficacy under a simplified model of adherence.

Anthropometric, cognitive, and schooling benefits of measles vaccination: Longitudinal cohort analysis in Ethiopia, India, and Vietnam

Objective

To estimate the associations between measles vaccination and child anthropometry, cognition, and schooling outcomes in Ethiopia, India, and Vietnam.

Methods

Longitudinal survey data from Young Lives were used to compare outcomes at ages 7–8 and 11–12 years between children who reported receipt or non-receipt of measles vaccine at 6–18 months-of-life (n = ∼2000/country). Z-scores of height-for-age (HAZ), BMI-for-age (BMIZ), weight-for-age (WAZ), Peabody Picture Vocabulary Test (PPVT), early grade reading assessment (EGRA), language and mathematics tests, and attained schooling grade were examined. Propensity score matching was used to control for systematic differences between measles-vaccinated and measles-unvaccinated children.

Findings

Using age- and country-matched measles-unvaccinated children as comparisons, measles-vaccinated children had better anthropometrics, cognition, and schooling. Measles-vaccinated children had 0.1 higher HAZ in India and 0.2 higher BMIZ and WAZ in Vietnam at age 7–8 years, and 0.2 higher BMIZ at age 11–12 years in Vietnam. At ages 7–8 years, they scored 4.5 and 2.9 percentage points (pp) more on PPVT and mathematics, and 2.3 points more on EGRA in Ethiopia, 2.5 points more on EGRA in India, and 2.6 pp, 4 pp, and 2.7 points more respectively on PPVT, mathematics, and EGRA in Vietnam. At ages 11–12 years, they scored 3 pp more on English and PPVT in India, and 1.7 pp more on PPVT in Vietnam. They also attained 0.2–0.3 additional schooling grades across all ages and countries.

Conclusion

Our findings suggest that measles vaccination may have benefits on cognitive gains and school-grade attainment that can have broad educational and economic consequences which extend beyond early childhood.