Cost-effectiveness and economic benefits of vaccines in low- and middle-income countries: a systematic review

The public health impact and cost-effectiveness of the R21/Matrix-M malaria vaccine: a mathematical modelling study

BACKGROUND

The R21/Matrix-M vaccine has demonstrated high efficacy against Plasmodium falciparum clinical malaria in children in sub-Saharan Africa. Using trial data, we aimed to estimate the public health impact and cost-effectiveness of vaccine introduction across sub-Saharan Africa.

METHODS

We fitted a semi-mechanistic model of the relationship between anti-circumsporozoite protein antibody titres and vaccine efficacy to data from 3 years of follow-up in the phase 2b trial of R21/Matrix-M in Nanoro, Burkina Faso. We validated the model by comparing predicted vaccine efficacy to that observed over 12-18 months in the phase 3 trial. Integrating this framework within a mathematical transmission model, we estimated the cases, malaria deaths, and disability-adjusted life-years (DALYs) averted and cost-effectiveness over a 15-year time horizon across a range of transmission settings in sub-Saharan Africa. Cost-effectiveness was estimated incorporating the cost of vaccine introduction (dose, consumables, and delivery) relative to existing interventions at baseline. We report estimates at a median of 20% parasite prevalence in children aged 2-10 years (PfPR2-10) and ranges from 3% to 65% PfPR2-10.

FINDINGS

Anti-circumsporozoite protein antibody titres were found to satisfy the criteria for a surrogate of protection for vaccine efficacy against clinical malaria. Age-based implementation of a four-dose regimen of R21/Matrix-M vaccine was estimated to avert 181 825 (range 38 815-333 491) clinical cases per 100 000 fully vaccinated children in perennial settings and 202 017 (29 868-405 702) clinical cases per 100 000 fully vaccinated children in seasonal settings. Similar estimates were obtained for seasonal or hybrid implementation. Under an assumed vaccine dose price of US$3, the incremental cost per clinical case averted was $7 (range 4-48) in perennial settings and $6 (3-63) in seasonal settings and the incremental cost per DALY averted was $34 (29-139) in perennial settings and $30 (22-172) in seasonal settings, with lower cost-effectiveness ratios in settings with higher PfPR2-10.

INTERPRETATION

Introduction of the R21/Matrix-M malaria vaccine could have a substantial public health benefit across sub-Saharan Africa.

FUNDING

The Wellcome Trust, the Bill & Melinda Gates Foundation, the UK Medical Research Council, the European and Developing Countries Clinical Trials Partnership 2 and 3, the NIHR Oxford Biomedical Research Centre, and the Serum Institute of India, Open Philanthropy.

Internet of Things (IoT)-enabled framework for a sustainable Vaccine cold chain management system

Vaccines are a unique category of drugs sensitive to temperature and humidity and whose effectiveness directly impacts public health. There has been an increase in vaccine-related adverse events worldwide, particularly in developing countries, attributed to suboptimal temperatures during transport and storage. At the same time, the Internet of Things (IoT) has ushered in a paradigm shift in vaccine information and storage monitoring, enabling continuous 24/7 tracking. This further reduces the dependence on limited human resources and significantly reduces the associated errors and losses. This paper presents an IoT-driven framework that aims to improve the sustainability of medical cold chain management. The framework promotes trust and transparency in vaccine surveillance data by accessing and authenticating IoT devices. The proposed system aims to improve the safety and sustainability of vaccine management. Moreover, we provide detailed insights into the design and hardware components of the proposed framework. In addition, the specific use of the framework in a particular province is highlighted, covering the design of the software platform and the analysis of the hardware equipment.

Twenty Years of Progress and the Way Forward: Immunization Registry Information System in Korea

The National Immunization Program in The Republic of Korea offers mandatory and free vaccinations to children under 12, regulated by the Infectious Disease Prevention and Control Act. Tracking vaccination coverage is crucial for population protection and public health strategies. Since 2002, the Immunization Registry Information System (IRIS) has been used nationwide to capture vaccination data. This study reviewed documents related to IRIS's establishment and development. The Republic of Korea legally supports IRIS's construction and data collection, integrating vaccination data with the Ministry of the Interior and Safety's resident registration to minimize errors. This collaboration also facilitates cost reimbursement and digital registration, promoting wider vaccination coverage. IRIS manages expense claims once vaccination details are logged, and authorized medical institutions can access these records in real-time. Since 2015, the Korea Disease Control and Prevention Agency has been compiling annual data on national vaccination coverage. IRIS also sends automated reminders in 12 languages, reports adverse effects, and issues vaccination certificates. However, IRIS lacks integration between vaccine and disease registries, unlike countries such as England, Denmark, and the Netherlands. Improving integration capabilities could enhance IRIS's support for public health through an integrated information system.

MA, Tovar-Rosero YY, Oñate AA, O'Ryan M. Two centuries of vaccination: historical and conceptual approach and future perspectives

Over the past two centuries, vaccines have been critical for the prevention of infectious diseases and are considered milestones in the medical and public health history. The World Health Organization estimates that vaccination currently prevents approximately 3.5-5 million deaths annually, attributed to diseases such as diphtheria, tetanus, pertussis, influenza, and measles. Vaccination has been instrumental in eradicating important pathogens, including the smallpox virus and wild poliovirus types 2 and 3. This narrative review offers a detailed journey through the history and advancements in vaccinology, tailored for healthcare workers. It traces pivotal milestones, beginning with the variolation practices in the early 17th century, the development of the first smallpox vaccine, and the continuous evolution and innovation in vaccine development up to the present day. We also briefly review immunological principles underlying vaccination, as well as the main vaccine types, with a special mention of the recently introduced mRNA vaccine technology. Additionally, we discuss the broad benefits of vaccines, including their role in reducing morbidity and mortality, and in fostering socioeconomic development in communities. Finally, we address the issue of vaccine hesitancy and discuss effective strategies to promote vaccine acceptance. Research, collaboration, and the widespread acceptance and use of vaccines are imperative for the continued success of vaccination programs in controlling and ultimately eradicating infectious diseases.

Understanding household-level risk factors for zero dose immunization in 82 low- and middle-income countries

INTRODUCTION

In 2021, an estimated 18 million children did not receive a single dose of routine vaccinations and constitute the population known as zero dose children. There is growing momentum and investment in reaching zero dose children and addressing the gross inequity in the reach of immunization services. To effectively do so, there is an urgent need to characterize more deeply the population of zero dose children and the barriers they face in accessing routine immunization services.

METHODS

We utilized the most recent DHS and MICS data spanning 2011 to 2020 from low, lower-middle, and upper-middle income countries. Zero dose status was defined as children aged 12-23 months who had not received any doses of BCG, DTP-containing, polio, and measles-containing vaccines. We estimated the prevalence of zero-dose children in the entire study sample, by country income level, and by region, and characterized the zero dose population by household-level factors. Multivariate logistic regressions were used to determine the household-level sociodemographic and health care access factors associated with zero dose immunization status. To pool multicountry data, we adjusted the original survey weights according to the country's population of children 12-23 months of age. To contextualize our findings, we utilized United Nations Population Division birth cohort data to estimate the study population as a proportion of the global and country income group populations.

RESULTS

We included a total of 82 countries in our univariate analyses and 68 countries in our multivariate model. Overall, 7.5% of the study population were zero dose children. More than half (51.9%) of this population was concentrated in African countries. Zero dose children were predominantly situated in rural areas (75.8%) and in households in the lowest two wealth quintiles (62.7%) and were born to mothers who completed fewer than four antenatal care (ANC) visits (66.5%) and had home births (58.5%). Yet, surprisingly, a considerable proportion of zero dose children's mothers did receive appropriate care during pregnancy (33.5% of zero dose children have mothers who received at least 4 ANC visits). When controlled for other factors, children had three times the odds (OR = 3.00, 95% CI: 2.72, 3.30) of being zero dose if their mother had not received any tetanus injections, 2.46 times the odds (95% CI: 2.21, 2.74) of being zero dose if their mother had not received any ANC visits, and had nearly twice the odds (OR = 1.87, 95% CI: 1.70, 2.05) of being zero dose if their mother had a home delivery, compared to children of mothers who received at least 2 tetanus injections, received at least 4 ANC visits, and had a facility delivery, respectively.

DISCUSSION

A lack of access to maternal health care was a strong risk factor of zero dose status and highlights important opportunities to improve the quality and integration of maternal and child health programs. Additionally, because a substantial proportion of zero dose children and their mothers do receive appropriate care, approaches to reach zero dose children should incorporate mitigating missed opportunities for vaccination.

Economic evaluations of immunization programs as an indispensable tool for policymakers

Introducing new vaccines within national immunization programs requires careful consideration of disease- and vaccine-related issues as well as of the strength of the program and the affected health system. Economic evaluations play an essential role in this process. In this editorial, we set the context and invite contributions for a BMC Health Services Research Collection of articles titled 'Economic Evaluations of Vaccine Programs'.

New Vaccine Introductions in WHO African Region between 2000 and 2022

Significant progress has been made in vaccine development worldwide. This study examined the WHO African Region's vaccine introduction trends from 2000 to 2022, excluding COVID-19 vaccines. We extracted data on vaccine introductions from the WHO/UNICEF joint reporting form for 17 vaccines. We examined the frequency and percentages of vaccine introductions from 2000 to 2022, as well as between two specific time periods (2000-2010 and 2011-2022). We analysed Gavi eligible and ineligible countries separately and used a Chi-squared test to determine if vaccine introductions differed significantly. Three vaccines have been introduced in all 47 countries within the region: hepatitis B (HepB), Haemophilus influenzae type b (Hib), and inactivated polio vaccine (IPV). Between 2011 and 2022, HepB, Hib, IPV, the second dose of measles-containing vaccine (MCV2), and pneumococcal conjugate vaccine (PCV) were the five most frequently introduced vaccines. Hepatitis A vaccine has only been introduced in Mauritius, while Japanese encephalitis vaccine has not been introduced in any African country. Between 2000-2010 and 2011-2022, a statistically significant rise in the number of vaccine introductions was noted (p < 0.001) with a significant positive association between Gavi eligibility and vaccine introductions (p < 0.001). Significant progress has been made in the introduction of new vaccines between 2000 and 2022 in the WHO African Region, with notable introductions between 2011 and 2022. Commitments from countries, and establishing the infrastructure required for effective implementation, remain crucial.

How to increase and maintain high immunization coverage: Vaccination Demand Resilience (VDR) framework

BACKGROUND

Resilience in vaccination demand is ever more critical as the COVID-19 pandemic has increased our understanding of the importance of vaccines on health and well-being. Yet timid demand for COVID-19 vaccines where available and reduced uptake of routine immunizations globally further raise the urgent need to build vaccination resilience. We demonstrate the complexity of vaccination demand and resilience in a framework where relevant dimensions are intertwined, fluid, and contextual.

METHODS

We developed the Vaccination Demand Resilience (VDR) framework based on a literature review on vaccination demand and expert consultation. The matrix framework builds on three main axes: 1) vaccination attitudes and beliefs; 2) vaccination seeking behavior; and 3) vaccination status. The matrix generated eight quadrants, which can help explain people's levels of vaccination demand and resilience. We selected four scenarios as examples to demonstrate different interventions that could move people across quadrants and build vaccination resilience.

RESULTS

Incongruence between individuals' attitudes and beliefs, vaccination behavior, and vaccination status can arise. For example, an individual can be vaccinated due to mandates but reject vaccination benefits and otherwise avoid seeking vaccination. Such incongruence could be altered by interventions to build resilience in vaccination demand. These interventions include information, education and communication to change individuals' vaccination attitudes and beliefs, incentive programs and reminder-recalls to facilitate vaccination seeking, or by strengthening healthcare provider communications to reduce missed opportunities.

CONCLUSIONS

Vaccination decision-making is complex. Individuals can be vaccinated without necessarily accepting the benefits of vaccination or seeking vaccination, threatening resilience in vaccination demand. The VDR framework can provide a useful lens for program managers and policy makers considering interventions and policies to improve vaccination resilience. This would help build and sustain confidence and demand for vaccinations, and help to continue to prevent disease, disability, and death from vaccine-preventable diseases.

Effect of COVID-19 on Routine Childhood Vaccination in Bahir Dar City, Northwestern, Ethiopia

Despite free vaccinations for all children, Ethiopia is one of the ten countries where most children do not receive all of their basic vaccines. The COVID-19 pandemic has disrupted service delivery and utilization worldwide. In this study, we assessed the effect of the pandemic on routine childhood vaccinations in Bahir Dar, Ethiopia. The data were collected from immunization records, health system monthly reports, and interviews with vaccination professionals. The data were analyzed using interrupted time series and thematic analyses. In 6940 records covering 2018-2022, the number of vaccine doses that were delivered steadily increased except for 2021/22. Vaccine delivery consistently increased prior to the pandemic. Immediately after the first case was reported, there were some disruptions, but they were not statistically significant compared to the pre-pandemic period. In-depth interviews also confirmed this finding, showing early pandemic fear and protective measures had an impact but were not sustained. These results show that COVID-19 has had a transient but non-significant effect on childhood vaccination. Although the interruption was statistically insignificant, it could reverse decades of progress toward safeguarding children from vaccine-preventable diseases. Therefore, we must intensify our initiatives to boost childhood vaccination rates and restore pre-pandemic services to regain momentum and avoid future setbacks.

Pay-it-forward influenza vaccination among older adults and children: A cost-effectiveness analysis in China

A quasi-experimental study was conducted to evaluate the effectiveness of a pay-it-forward strategy for increasing influenza vaccination among children and older adults compared to a self-paid vaccination strategy in China. Pay-it-forward is an innovative community-engaged intervention in which participants receive a free influenza vaccination and are then asked if they would like to donate or create a message to support subsequent vaccinations. This economic evaluation used a decision-tree model to compare pay-it-forward to a standard of care arm in which patients had to pay for their own influenza vaccine. The analysis was performed from the healthcare provider perspective and costs were calculated with 2020 United States dollars. The time horizon was one year. In the base case analysis, pay-it-forward was more effective (111 vs 55 people vaccinated) but more costly than standard-of-care ($4477 vs $2725). Pay-it-forward spurred 96.4% (107/111) of individuals to voluntarily donate to support influenza vaccination for high-risk groups in China. Further costing and implementation research is needed to inform scale up.

Willingness to pay for hepatitis B virus vaccine and associated factors among households in Bahir Dar City, northwest Ethiopia: using contingent valuation method

Background

The prevention of disease burden and death through vaccination is one of the most cost-effective methods. Even though the Hepatitis B Virus (HBV) has significant public health problems in Ethiopia, there is no compulsory HBV vaccination program for adults and the vaccine's market value was not yet estimated in the Ethiopia context. Therefore, this study aimed to assess the willingness to pay (WTP) for the HBV vaccine and its associated factors among households in Bahir Dar City, northwest Ethiopia.

Methods

A cross-sectional study was conducted among 620 households from March 1 to 30, 2020. A systematic random sampling technique was employed to select the required number of households. An interviewer-administered questionnaire was used to collect the necessary information. The contingent valuation method was conducted to measure WTP for the HBV vaccine. A Tobit regression model was employed to investigate significantly associated factors, and variables with a p-value of <0.05 were considered statistically significant.

Results

In this study, 62.17% of households were willing to pay for the HBV vaccine with an average cost of ETB174.24 (US$5.25). Male household heads (P = 0.014), favorable attitude (P = 0.017), and good knowledge (P < 0.001) toward the vaccine were positively associated with WTP, whereas age (P < 0.001), single marital status (P = 0.012) and divorced/widowed (P = 0.018) marital status were negatively associated with WTP.

Conclusions

Overall, most households were willing to pay for the HBV vaccine with an average demand of ETB174.24 (US$5.25). Therefore, a national-level HBV vaccine strategy should be designed considering the households' willingness to pay. In addition, working on attitudes and knowledge toward the vaccine could potentially increase the household's willingness to pay for the HBV vaccine.

The Full Value of Vaccine Assessments (FVVA): a framework for assessing and communicating the value of vaccines for investment and introduction decision-making

BACKGROUND

Several economic obstacles can deter the development and use of vaccines. This can lead to limited product options for some diseases, delays in new product development, and inequitable access to vaccines. Although seemingly distinct, these obstacles are actually interrelated and therefore need to be addressed through a single over-arching strategy encompassing all stakeholders.

METHODS

To help overcome these obstacles, we propose a new approach, the Full Value of Vaccines Assessments (FVVA) framework, to guide the assessment and communication of the value of a vaccine. The FVVA framework is designed to facilitate alignment across key stakeholders and to enhance decision-making around investment in vaccine development, policy-making, procurement, and introduction, particularly for vaccines intended for use in low- and middle-income countries.

RESULTS

The FVVA framework has three key elements. First, to enhance assessment, existing value-assessment methods and tools are adapted to include broader benefits of vaccines as well as opportunity costs borne by stakeholders. Second, to improve decision-making, a deliberative process is required to recognize the agency of stakeholders and to ensure country ownership of decision-making and priority setting. Third, the FVVA framework provides a consistent and evidence-based approach that facilitates communication about the full value of vaccines, helping to enhance alignment and coordination across diverse stakeholders.

CONCLUSIONS

The FVVA framework provides guidance for stakeholders organizing global-level efforts to promote investment in vaccines that are priorities for LMICs. By providing a more holistic view of the benefits of vaccines, its application also has the potential to encourage greater take-up by countries, thereby leading to more sustainable and equitable impacts of vaccines and immunization programmes.

Projecting the long-term economic benefits of reducing Shigella-attributable linear growth faltering with a potential vaccine: a modelling study

BACKGROUND

Linear growth is an important outcome of child development with implications for economic productivity. Enteric infections, particularly Shigella, have been linked to linear growth faltering (LGF). However, benefits from potential reductions in LGF are rarely included in economic analyses of enteric infections. We aimed to quantify the economic benefits of vaccination related to reduced Shigella-attributable disease and associated LGF compared with the net costs of a vaccine programme.

METHODS

In this benefit-cost analysis, we modelled productivity benefits in 102 low-income and middle-income countries that had recent stunting estimates available, at least one Shigella-attributable death annually, and available economic data, particularly on gross national income and growth rate projections. We modelled benefits strictly related to linear growth improvements and no other benefits associated with reducing diarrhoeal burden. The effect size in each country was calculated as shifts in height-for-age Z score (HAZ), representing population average changes for preventing Shigella-attributable less-severe diarrhoea and moderate-to-severe diarrhoea separately for children younger than 5 years. Benefits data were calculated per country and combined with estimated net costs of the vaccine programme in the form of benefit-cost ratios (BCRs); BCRs above parity, or $1 in benefits per $1 in costs (with a 10% margin representing borderline results: 1·10:1), were considered cost-beneficial. Countries were aggregated for analysis by WHO region, World Bank income category, and eligibility for support from Gavi, the Vaccine Alliance.

FINDINGS

In the base-case scenario, all regions exhibited cost-beneficial results, with the South-East Asia region and Gavi-eligible countries exhibiting the highest BCRs (21·67 for the South-East Asia region and 14·45 for Gavi-eligible countries), and the Eastern Mediterranean region yielding the lowest BCRs (2·90). All regions exhibited cost-beneficial results from vaccination, except in more conservative scenarios (eg, those assuming early retirement ages and higher discount rates). Our findings were sensitive to assumed returns for increased height, assumptions about vaccine efficacy against linear growth detriments, the anticipated shift in HAZ, and discount rate. Incorporating the productivity benefits of LGF reduction into existing cost-effectiveness estimates resulted in longer-term cost-savings in nearly all regions.

INTERPRETATION

LGF is a secondary outcome of Shigella infection and reduction in LGF is not often quantified as a health or economic benefit of vaccination. However, even under conservative assumptions, a Shigella vaccine only moderately effective against LGF could pay for itself from productivity gains alone in some regions. We recommend that LGF be considered in future models assessing the economic and health impacts of interventions preventing enteric infections. Further research is needed on vaccine efficacy against LGF to inform such models.

FUNDING

Bill & Melinda Gates Foundation, Wellcome Trust.

A cultural evolutionary model of the interaction between parental beliefs and behaviors, with applications to vaccine hesitancy

Health perceptions and health-related behaviors can change at the population level as cultures evolve. In the last decade, despite the proven efficacy of vaccines, the developed world has seen a resurgence of vaccine-preventable diseases (VPDs) such as measles, pertussis, and polio. Vaccine hesitancy, an individual attitude influenced by historical, political, and socio-cultural forces, is believed to be a primary factor responsible for decreasing vaccine coverage, thereby increasing the risk and occurrence of VPD outbreaks. Behavior change models have been increasingly employed to understand disease dynamics and intervention effectiveness. However, since health behaviors are culturally influenced, it is valuable to examine them within a cultural evolution context. Here, using a mathematical modeling framework, we explore the effects of cultural evolution on vaccine hesitancy and vaccination behavior. With this model, we shed light on facets of cultural evolution (vertical transmission, community influences, homophily, etc.) that promote the spread of vaccine hesitancy, ultimately affecting levels of vaccination coverage and VPD outbreak risk in a population. In addition, we present our model as a generalizable framework for exploring cultural evolution when humans' beliefs influence, but do not strictly dictate, their behaviors. This model offers a means of exploring how parents' potentially conflicting beliefs and cultural traits could affect their children's health and fitness. We show that vaccine confidence and vaccine-conferred benefits can both be driving forces of vaccine coverage. We also demonstrate that an assortative preference among vaccine-hesitant individuals can lead to increased vaccine hesitancy and lower vaccine coverage.

Out-of-pocket expenditures and financial risks associated with treatment of vaccine-preventable diseases in Ethiopia: A cross-sectional costing analysis

BACKGROUND

Vaccine-preventable diseases (VPDs) remain major causes of morbidity and mortality in low- and middle-income countries (LMICs). Universal access to vaccination, besides improved health outcomes, would substantially reduce VPD-related out-of-pocket (OOP) expenditures and associated financial risks. This paper aims to estimate the extent of OOP expenditures and the magnitude of the associated catastrophic health expenditures (CHEs) for selected VPDs in Ethiopia.

METHODS AND FINDINGS

We conducted a cross-sectional costing analysis, from the household (patient) perspective, of care-seeking for VPDs in children aged under 5 years for pneumonia, diarrhea, measles, and pertussis, and in children aged under 15 years for meningitis. Data on OOP direct medical and nonmedical expenditures (2021 USD) and household consumption expenditures were collected from 995 households (1 child per household) in 54 health facilities nationwide between May 1 and July 31, 2021. We used descriptive statistics to measure the main outcomes: magnitude of OOP expenditures, along with the associated CHE within households. Drivers of CHE were assessed using a logistic regression model. The mean OOP expenditures per disease episode for outpatient care for diarrhea, pneumonia, pertussis, and measles were $5·6 (95% confidence interval (CI): $4·3, 6·8), $7·8 ($5·3, 10·3), $9·0 ($6·4, 11·6), and $7·4 ($3·0, 11·9), respectively. The mean OOP expenditures were higher for inpatient care, ranging from $40·6 (95% CI: $12·9, 68·3) for severe measles to $101·7 ($88·5, 114·8) for meningitis. Direct medical expenditures, particularly drug and supply expenses, were the major cost drivers. Among those who sought inpatient care (345 households), about 13·3% suffered CHE, at a 10% threshold of annual consumption expenditures. The type of facility visited, receiving inpatient care, and wealth were significant predictors of CHE (p-value < 0·001) while adjusting for area of residence (urban/rural), diagnosis, age of respondent, and household family size. Limitations include inadequate number of measles and pertussis cases.

CONCLUSIONS

The OOP expenditures induced by VPDs are substantial in Ethiopia and disproportionately impact those with low income and those requiring inpatient care. Expanding equitable access to vaccines cannot be overemphasized, for both health and economic reasons. Such realization requires the government's commitment toward increasing and sustaining vaccine financing in Ethiopia.

Homologous booster immunization with an inactivated vaccine induced robust antibody response in healthcare workers: A retrospective study

Coronavirus Disease 2019 (Covid-19) severely impacted the health, society, and economy around the world. With declining protective efficacy of primary vaccination and the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, a Covid-19 booster vaccination is being fully implemented globally. Many people received three doses of BBIBP-CorV inactivated vaccine in China and other developing countries. However, the antibody response and immune persistence of the homologous BBIBP-CorV booster vaccination is yet to be thoroughly evaluated, as previous studies focused within one month after the third dose. In this study, 97 participants were enrolled to analyze the antibody response and immune persistence within 6 months as well as the safety within 7 days after the third-dose of homologous BBIBP-CorV inactivated vaccine. The seroconversion rate for total antibody against the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein were both 100% at month 1 and month 6 after the third dose. The IgG against the RBD of the SARS-CoV-2 S protein seroconversion rate increased from 42.27% before the third dose to 100% 1 month after the third dose and then slightly decreased to 98.97% 5 months later. Positive IgM against the RBD of the SARS-CoV-2 S protein was rare and was observed in only one participant at month 1 after the third dose. The neutralizing antibody levels at month 1 and month 6 after the third dose increased 63.32-fold and 13.16-fold compared with those before the third dose, and the positive rate for neutralizing antibody was still 100% at month 6 after the third dose. Importantly, the antibody responses induced by the vaccine and immune persistence were not affected by sex or age. No serious adverse reactions were reported. Total antibody and IgG against the RBD of the SARS-CoV-2 S protein were highly correlated with neutralizing antibody, suggesting that total antibody and IgG against the RBD of the SARS-CoV-2 S protein could be used as predictors for neutralizing antibody. In conclusion, the third dose of homologous BBIBP-CorV inactivated vaccine induced a robust antibody response and moderate immune persistence. These finding are of great significance for development future vaccination strategies.

Dynamic mechanism of eliminating COVID-19 vaccine hesitancy through web search

This research focuses on the research problem of eliminating COVID-19 vaccine hesitancy through web search. A dynamic model of eliminating COVID-19 vaccine hesitancy through web search is constructed based on the Logistic model, the elimination degree is quantified, the elimination function is defined to analyze the dynamic elimination effect, and the model parameter estimation method is proposed. The numerical solution, process parameters, initial value parameters and stationary point parameters of the model are simulated, respectively, and the mechanism of elimination is deeply analyzed to determine the key time period. Based on the real data of web search and COVID-19 vaccination, data modeling is carried out from two aspects: full sample and segmented sample, and the rationality of the model is verified. On this basis, the model is used to carry out dynamic prediction and verified to have certain medium-term prediction ability. Through this research, the methods of eliminating vaccine hesitancy are enriched, and a new practical idea is provided for eliminating vaccine hesitancy. It also provides a method to predict the quantity of COVID-19 vaccination, provides theoretical guidance for dynamically adjusting the public health policy of the COVID-19, and can provide reference for the vaccination of other vaccines.

Essential childhood immunization in 43 low- and middle-income countries: Analysis of spatial trends and socioeconomic inequalities in vaccine coverage

BACKGROUND

Globally, access to life-saving vaccines has improved considerably in the past 5 decades. However, progress has started to slow down and even reverse in recent years. Understanding subnational heterogeneities in essential child immunization will be critical for closing the global vaccination gap.

METHODS AND FINDINGS

We use vaccination information for over 220,000 children across 1,366 administrative regions in 43 low- and middle-income countries (LMICs) from the most recent Demographic and Health Surveys. We estimate essential immunization coverage at the national and subnational levels and quantify socioeconomic inequalities in such coverage using adjusted concentration indices. Within- and between-country variations are summarized via the Theil index. We use local indicator of spatial association (LISA) statistics to identify clusters of administrative regions with high or low values. Finally, we estimate the number of missed vaccinations among children aged 15 to 35 months across all 43 countries and the types of vaccines most often missed. We show that national-level vaccination rates can conceal wide subnational heterogeneities. Large gaps in child immunization are found across West and Central Africa and in South Asia, particularly in regions of Angola, Chad, Nigeria, Guinea, and Afghanistan, where less than 10% of children are fully immunized. Furthermore, children living in these countries consistently lack all 4 basic vaccines included in the WHO's recommended schedule for young children. Across most countries, children from poorer households are less likely to be fully immunized. The main limitations include subnational estimates based on large administrative divisions for some countries and different periods of survey data collection.

CONCLUSIONS

The identified heterogeneities in essential childhood immunization, especially given that some regions consistently are underserved for all basic vaccines, can be used to inform the design and implementation of localized intervention programs aimed at eliminating child suffering and deaths from existing and novel vaccine-preventable diseases.

Financing Comprehensive Immunization Services in Lao PDR: A Fiscal Space Analysis From a Public Policy Perspective

INTRODUCTION

A comprehensive package of immunization services is an internal component of the Essential Health Service Package (ESP) implemented by Government of Lao People's Democratic Republic (Lao PDR). Thus, the cost of delivering the immunization program and its feasibility given the fiscal space emerges as an important policy question. The present analysis was undertaken to estimate the total cost of implementing the immunization program under ESP, determinants of total cost and the program's fiscal implications from the government's perspective.

METHODOLOGY

We employed a normative costing approach for costing of immunization services under ESP. Standard treatment guidelines (STGs) from both within and outside Lao PDR were considered to identify the resource use for each vaccine delivery. Subsequently, cost per dose administered and fully immunized beneficiary were computed. We assessed the fiscal space for financing immunization services in Lao PDR by adapting the decomposition method given by Tandon et al. RESULTS: In 2019, the estimated total cost of financing immunization in Lao PDR was US$12 million, which will increase in 2025 by 1.75 times, to US$21 million. The per capita budget for immunization needs to increase from about US$2 to US$7. Introduction of newer vaccines in the immunization schedule accounts for the major share (60%) of the increased cost for financing immunization. In view of current fiscal space, the government immunization expenditure (GIE) allocations will be adequate only in a scenario where no new vaccine is introduced under ESP in future years.

CONCLUSION

The current fiscal space would fall short of meeting the aspirational goals of ESP-Immunization for the introduction of newer vaccines in Lao PDR. The present analysis of the fiscal space provides important evidence to support a greater role for the Global Alliance for Vaccine Initiative (GAVI) to continue to finance immunization in Lao PDR. A publicly financed immunization model in Lao PDR would require significant strategic amendments with low short-term viability.

Business or Hope? The Vaccine of the Day after, a Life Expectancy

This approach reflects the moments when humanity was infected by the new pandemic from a health point of view. The acceleration to find the vaccine that will protect us from the pandemic brings some interesting questions from the point of view of possible side effects and from the point of view of the economy. The growing interest in first producing the so-called ‘morning after’ vaccine calls into question whether this is a purely scientific act open to all countries of the world free of charge. Along the way, there are still the interests of many companies that have been favoured in one way or another to increase their profits. The analysis exposes the paradigm of health versus economy, of life expectancy versus business. Within this framework, humanity is discussed as a balance, perhaps taken advantage of by some of the biotechnology and pharmaceutical companies located in the strongest countries in the market, to the detriment of the weakest.

Use of community engagement interventions to improve child immunisation in low- and middle-income countries: A systematic review and meta-analysis

Immunisation is one of the most cost-effective interventions to prevent and control life-threatening infectious diseases. Nonetheless, rates of routine vaccination of children in low- and middle-income countries (LMICs) are strikingly low or stagnant. In 2019, an estimated 19.7 million infants did not receive routine immunisations. Community engagement interventions are increasingly being emphasised in international and national policy frameworks as a means to improve immunisation coverage and reach marginalised communities. This systematic review examines the effectiveness and cost-effectiveness of community engagement interventions on outcomes related to childhood immunisation in LMICs and identifies contextual, design and implementation features that may be associated with effectiveness. We identified 61 quantitative and mixed methods impact evaluations and 47 associated qualitative studies related to community engagement interventions for inclusion in the reteview. For cost-effectiveness analysis 14 of the 61 studies had the needed combination of cost and effectiveness data. The 61 included impact evaluations were concentrated in South Asia and Sub-Saharan Africa and spread across 19 LMICs. The review found that community engagement interventions had a small but significant, positive effect on all primary immunisation outcomes related to coverage and their timeliness. The findings are robust to exclusion of studies assessed as high risk of bias. Qualitative evidence indicates appropriate intervention design, including building in community engagement features; addressing common contextual barriers of immunisation and leveraging facilitators; and accounting for existing implementation constraints and practicalities on the ground are consistently cited as reasons for intervention success. Among the studies for which we were able to calculate cost-effectiveness, we find that the median non-vaccine cost per dose of intervention to increase immunisation coverage by 1% was US $3.68. Given the broad scope of the review in terms of interventions and outcomes, there is significant variation in findings. Among the various types of community engagement interventions, those that involve creation of community buy-in or development of new cadres of community-based structures were found to have consistent positive effect on more primary vaccination coverage outcomes than if the engagement is limited to the design or delivery of an intervention or is a combination of the various types. The evidence base for sub-group analysis for female children was sparse (only two studies) and the effect on coverage of both full immunisation and third dose of diphtheria pertussis tetanus for this group was insignificant.

Vaccine financing in the Middle East and Africa: An overview from 2010 to 2019

BACKGROUND

Vaccination is a cost-effective disease prevention measure. Sustainable financing is critical to successful implementation of vaccination programs. Countries in the Middle East and Africa (MEA) have vaccination programs that remain highly vulnerable to budget limitations.

OBJECTIVES

The objectives of this study were to understand the current vaccine financing landscape in MEA; to assess the availability and variability of data on vaccination budgets, expenditure and schedules including introductions of new vaccines; and to identify and describe key trends.

METHOD

A targeted literature review was conducted for 69 MEA countries for data between 2010 and 2019. Descriptive analysis of the collected data was conducted.

RESULTS

Data on vaccination expenditure were available for 96% of the countries. However, data on vaccination budget were limited, and the variability was high. The median vaccination expenditure per capita was between US$0.57 and US$1.02. High-income countries spent the most on vaccination per capita (median US$3.41) compared to low-income countries (median US$0.69). The highest vaccination expenditure per capita was in countries that receive 100% government funding of vaccination programs (US$0.87) compared to those where government pays for > 0% to < 50% of vaccination expenditure (US$0.74). Vaccination expenditure as a proportion of gross domestic product was the highest (0.10%) in low-income countries and the lowest in high-income countries (0.01%). Vaccination expenditure as proportion of healthcare expenditure was the highest (1.76%) in low-income countries and the lowest in high-income countries (0.33%). Statistically significant trends in median expenditure per capita were identified for 27% of the countries. During this period, an average of 4.4 vaccines were introduced.

CONCLUSION

Data on vaccination expenditure in MEA was available for detailed analysis, and it was useful to understand the characteristics of vaccination funding in the region. It is important to secure adequate financing to sustain current vaccination programs and to introduce new vaccines.

The minimal COVID-19 vaccination coverage and efficacy to compensate for a potential increase of transmission contacts, and increased transmission probability of the emerging strains

Background

Mass immunization is a potentially effective approach to finally control the local outbreak and global spread of the COVID-19 pandemic. However, it can also lead to undesirable outcomes if mass vaccination results in increased transmission of effective contacts and relaxation of other public health interventions due to the perceived immunity from the vaccine.

Methods

We designed a mathematical model of COVID-19 transmission dynamics that takes into consideration the epidemiological status, public health intervention status (quarantined/isolated), immunity status of the population, and strain variations. Comparing the control reproduction numbers and the final epidemic sizes (attack rate) in the cases with and without vaccination, we quantified some key factors determining when vaccination in the population is beneficial for preventing and controlling future outbreaks.

Results

Our analyses predicted that there is a critical (minimal) vaccine efficacy rate (or a critical quarantine rate) below which the control reproduction number with vaccination is higher than that without vaccination, and the final attack rate in the population is also higher with the vaccination. We also predicted the worst case scenario occurs when a high vaccine coverage rate is achieved for a vaccine with a lower efficacy rate and when the vaccines increase the transmission efficient contacts.

Conclusions

The analyses show that an immunization program with a vaccine efficacy rate below the predicted critical values will not be as effective as simply investing in the contact tracing/quarantine/isolation implementation. We reached similar conclusions by considering the final epidemic size (or attack rates). This research then highlights the importance of monitoring the impact on transmissibility and vaccine efficacy of emerging strains.

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.

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.

Impact of the COVID-19 pandemic on the vaccination of children 12 months of age and under: an ecological study

This study aimed to evaluate the impact of the COVID-19 pandemic on the vaccination numbers for immunization geared toward individuals under 12 months of age in Brazil. This study analyzed the numbers of the nationwide vaccination coverage of ten vaccines present in the calendar from the National Immunization Program (NIP) over the past eight years (2013-2020). This is an ecological study, and all data were taken from the NIP. In comparison to the previous years, 2020 recorded the lowest figures of vaccination coverage (VC) of the average of the group of studied vaccines - 79.07% - while in 2019, this same index was 84.44%, resulting in a drop of 11.10% between these two periods. Moreover, during the year of the pandemic, of the ten analyzed vaccines, nine recorded their lowest historical VC figures, all of which were at least 14 percentage points below the goals set by the Brazilian Ministry of Health (MS, in Portuguese). Although there had already been a tendency toward a decline in VC, for various reasons, the present study illustrates that the numbers recorded in 2020 were significantly lower, a phenomenon also reported in other countries. Therefore, although it is impossible to affirm that the COVID-19 pandemic and its distancing measures are the causes for the drop in the immunization numbers, it can be inferred that there is indeed an association.

National Health Spending, Health-Care Resources, Service Utilization, and Health Outcomes

Cross-national studies of the linkage of health-care spending with population health have found surprisingly limited evidence of benefits. In this study, we investigated associations between national health spending and key health resources (numbers of hospital beds, physicians, and nurses) and utilization of cost-effective health services (antenatal care, attendance of trained staff at childbirth, and measles vaccination), sometimes in ways that curtail the benefits of that expenditure. Using annual panel data from 1990-2014 covering 140 countries, we show that variation in health spending as a share of gross domestic product is not associated with decreased mortality rates. It is also very weakly associated with increased health-care resources and health service utilization (elasticity smaller than 0.08), with the association being close to 0 in low-income countries. In addition, countries with a higher share of out-of-pocket spending have a significantly lower level of health resources and service utilization. These findings, rather than the ineffectiveness of health care, could explain the lack of impact of health spending. In contrast, gross domestic product per capita is significantly associated with increased health resources, a higher rate of service utilization, and lower mortality rates, suggesting that income is an important determinant of public health.

Childhood immunization during the COVID-19 pandemic: experiences in Haiti, Lesotho, Liberia and Malawi

Objective

To examine changes in vaccination of children younger than 1 year during the coronavirus disease 2019 (COVID-19) pandemic (March 2020–August 2021) in Haiti, Lesotho, Liberia and Malawi.

Methods

We used data from health management information systems on vaccination of children aged 12 months or younger in districts supported by Partners In Health. We used data from January 2016 to February 2020 and a linear model with negative binomial distribution to estimate the expected immunization counts for March 2020–August 2021 with 95% prediction intervals, assuming no pandemic. We compared these expected levels with observed values and estimated the immunization deficits or excesses during the pandemic months.

Findings

Baseline vaccination counts varied substantially by country, with Lesotho having the lowest count and Haiti the highest. We observed declines in vaccination administration early in the COVID-19 pandemic in Haiti, Lesotho and Liberia. Continued declines largely corresponded to high rates of COVID-19 infection and discrete stock-outs. By August 2021, vaccination levels had returned to close to or above expected levels in Haiti, Liberia and Lesotho; in Malawi levels remained below expected.

Conclusion

Patterns of childhood immunization coverage varied by country over the course of the pandemic, with significantly lower than expected vaccination levels seen in one country during subsequent COVID-19 waves. Governments and health-care stakeholders should monitor vaccine coverage closely and consider interventions, such as community outreach, to avoid or combat the disruptions in childhood vaccination.

OUP accepted manuscript

Background

The coronavirus disease 2019 (COVID-19) pandemic has led to disruption in delivering routine healthcare services including routine immunization (RI) worldwide. Understanding the enablers and barriers for RI services during a pandemic is critically important to develop context-appropriate strategies to ensure uninterrupted routine services.

Methods

A community-based, cross-sectional descriptive study was conducted in five different states of India, nested within an ongoing multicentric study on RI. Telephone in-depth interviews among 56 health workers were carried out and the data were analyzed using a content analysis method.

Results

During the COVID-19 pandemic, healthcare providers encountered many challenges at the health system, community and individual level when rendering RI services. Challenges like the limited availability of personal protective equipment and vaccines, deployment for COVID-19 duty at system level, the difficulty in mobilizing people in the community, fear among people at community level, mobility restrictions and limited family support, as well as the stress and stigma at individual level, were barriers to providing RI services. By contrast, the issuing of identification cards to health staff, engaging community volunteers, the support given to health workers by their families and training on COVID-19, were factors that enabled health workers to maintain RI services during the pandemic.

Conclusions

When addressing the COVID-19–related public health emergency, we should not lose sight of the importance of services like RI.

Effect of measles prevalence and vaccination coverage on other disease burden: evidence of measles immune amnesia in 46 African countries

BACKGROUND

Measles is highly infectious that leads to a high disease burden among the vulnerable population, especially in developing countries, despite the availability of highly effective measles vaccine. Immune amnesia, the resetting of the immune systems of infected patients, has been observed in developed countries. This paper is the first to use various African countries to evaluate the extent of immune amnesia.

METHODS

We used two panel datasets from 46 African countries between 1990 and 2018 among children, one is the disease prevalence from Global Burden of Disease, and another is on the measles vaccination coverage from WHO/UNICEF Joint Reporting Form. We used panel regression to estimate the effect of measles prevalence or measles vaccination coverage on other disease prevalence (diarrhea, lower respiratory infection, malaria, meningitis, and tuberculosis).

RESULTS

We found the strong evidence that the increase in the measles prevalence led to an increase in other disease prevalence and mortality. We also found that the increase in the measles vaccination coverage decreased the prevalence of and the mortality due to other diseases.

DISCUSSION AND CONCLUSION

Measles vaccination can have a large impact on children's health because not only does it reduce the prevalence of measles cases and deaths but also could it potentially reduce the prevalence of and deaths due to other diseases.

Inclusion of Additional Unintended Consequences in Economic Evaluation: A Systematic Review of Immunization and Tuberculosis Cost-Effectiveness Analyses

OBJECTIVE

Our objective was to review economic evaluations of immunization and tuberculosis to determine the extent to which additional unintended consequences were taken into account in the analysis and to describe the methodological approaches used to estimate these, where possible.

METHODS

We sourced the vaccine economic evaluations from a previous systematic review by Nymark et al. (2009-2015) and searched PubMed/MEDLINE and Embase from 2015 to 2019 using the same search strategy. For tuberculosis economic evaluations, we extracted studies from 2009 to 2019 that were published in a previous review by Siapka et al. We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance. Studies were classified according to the categories and subcategories (e.g., herd immunity, non-specific effects, and labor productivity) defined in a framework identifying additional unintended consequences by Nymark and Vassall. Where possible, methods for estimating the additional unintended consequences categories and subcategories were described. We evaluated the reporting quality of included studies according to the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) extraction guideline.

RESULTS

We identified 177 vaccine cost-effectiveness analyses (CEAs) between 2009 and 2019 that met the inclusion criteria. Of these, 98 included unintended consequences. Of the total 98 CEAs, overall health consequence categories were included 73 times; biological categories: herd immunity 43 times; pathogen response: resistance 15 times; and cross-protection 15 times. For health consequences pertaining to the supply-side (health systems) categories, side effects were included five times. On the nonhealth demand side (intrahousehold), labor productivity was included 60 times. We identified 29 tuberculosis CEAs from 2009 to 2019 that met the inclusion criteria. Of these, six articles included labor productivity, four included indirect transmission effects, and one included resistance. Between 2009 and 2019, only 34% of tuberculosis CEAs included additional unintended consequences, compared with 55% of vaccine CEAs.

CONCLUSIONS

The inclusion of additional unintended consequences in economic evaluations of immunization and tuberculosis continues to be limited. Additional unintended consequences of economic benefits, such as those examined in this review and especially those that occur outside the health system, offer valuable information to analysts. Further work on appropriate ways to value these additional unintended consequences is still warranted.

The economic burden of rotavirus hospitalization among children < 5 years of age in selected hospitals in Bangladesh

BACKGROUND

Rotavirus is a common cause of severe acute gastroenteritis among young children. Estimation of the economic burden would provide informed decision about investment on prevention strategies (e.g., vaccine and/or behavior change), which has been a potential policy discussion in Bangladesh for several years.

METHODS

We estimated the societal costs of children <5 years for hospitalization from rotavirus gastroenteritis (RVGE) and incidences of catastrophic health expenditure. A total of 360 children with stool specimens positive for rotavirus were included in this study from 6 tertiary hospitals (3 public and 3 private). We interviewed the caregiver of the patient and hospital staff to collect cost from patient and health facility perspectives. We estimated the economic cost considering 2015 as the reference year.

RESULTS

The total societal per-patient costs to treat RVGE in the public hospital were 126 USD (95% CI: 116-136) and total household costs were 161 USD (95% CI: 145-177) in private facilities. Direct costs constituted 38.1% of total household costs. The out-of-pocket payments for RVGE hospitalization was 23% of monthly income and 76% of households faced catastrophic healthcare expenditures due to this expense. The estimated total annual household treatment cost for the country was 10 million USD.

CONCLUSIONS

A substantial economic burden of RVGE in Bangladesh was observed in this study. Any prevention of RVGE through cost-effective vaccination or/and behavioural change would contribute to substantial economic benefits to Bangladesh.

Impact of COVID-19 Pandemic on Childhood Immunization in a Tertiary Health-Care Center

Background:

After the emergence of COVID-19 pandemic, health facilities nationwide became the battleground for COVID-19. Many hospitals are designated as COVID-19 hospitals and various measures taken by the government to contain the spread of infection have disrupted the provision of routine health-care services including immunization. The aim of this study is to describe the impact of COVID-19 pandemic on immunization in a tertiary level health-care facility.

Materials and Methodology:

Data of children vaccinated as per the Universal immunization program (UIP) schedule were retrieved from immunizations records for a 7 month (January to July) period for the years 2019 and 2020. The trends of vaccination during COVID-19 pandemic are studied and are compared with the date matched data of the previous year.

Results:

There was a significant drop in the vaccine counts after emergence of COVID-19 pandemic. Maximum drop (−87%) was seen during the month of April (76.52% ± 43.62% vs. 16.95% ± 42.55%; P < 0.001) followed by May and June when it was −67% and −33%, respectively.

Conclusion:

COVID-19 pandemic has created the gaps in immunization which requires immediate attention. Further failure in sustaining the vaccination services and weak catch-up plans can lead to the emergence of vaccine-preventable diseases which may result in increased childhood morbidity and mortality.

Frequency and impact of the inclusion of broader measures of value in economic evaluations of vaccines

BACKGROUND

The health and economic benefits of immunization may extend beyond the elements traditionally included in cost-effectiveness analyses (CEAs). This review investigated how broader impacts are considered in economic evaluations of vaccines and whether their inclusion would substantially change CEA findings.

METHODS

We reviewed CEAs of vaccines associated with the largest global health burden, published from 2014 to 2019 using the Tufts CEA Registry and Tufts Global Health CEA Registry. We supplemented this with a systematic review of published and grey literature. We conducted descriptive analyses to examine the frequency of inclusion of specific social factors and study characteristics associated with their inclusion. We also conducted a case study of the human papilloma virus (HPV) vaccine to illustrate the potential change in CEA findings from selected social impacts.

RESULTS

We identified 475 relevant health economic assessments. Overall, 40% of studies included at least one category of social impact. The most commonly included non-healthcare cost among cost-per-QALY studies was productivity (25%), while cost-per-DALY studies reported transportation costs most frequently (24%). Few studies examined the impact of vaccination on other sectors such as education and housing (<3%). Middle-income and North American settings were positively associated with social impact inclusion, while sub-Saharan African location was negatively associated. In the HPV case study, the addition of nonhealth costs improved cost-effectiveness by up to 90% or made the vaccine cost-saving, depending on geographic setting. The cost-saving scenario saved up to $30,000 in costs per case of cervical cancer averted.

CONCLUSIONS

A minority of vaccine CEAs include social impacts, particularly for nonhealth sectors. The omission of these impacts may result in a systematic undervaluation of vaccines from a societal perspective. Further efforts are required to document the full benefits of vaccination for policymaker consideration.

Overcoming roadblocks in the development of vaccines for leishmaniasis

INTRODUCTION

The leishmaniases represent a group of parasitic diseases caused by infection with one of several species of Leishmania parasites. Disease presentation varies because of differences in parasite and host genetics and may be influenced by additional factors such as host nutritional status or co-infection. Studies in experimental models of Leishmania infection, vaccination of companion animals and human epidemiological data suggest that many forms of leishmaniasis could be prevented by vaccination, but no vaccines are currently available for human use.

AREAS COVERED

We describe some of the existing roadblocks to the development and implementation of an effective leishmaniasis vaccine, based on a review of recent literature found on PubMed, BioRxiv and MedRxiv. In addition to discussing scientific unknowns that hinder vaccine candidate identification and selection, we explore gaps in knowledge regarding the commercial and public health value propositions underpinning vaccine development and provide a route map for future research and advocacy.

EXPERT OPINION

Despite significant progress, leishmaniasis vaccine development remains hindered by significant gaps in understanding that span the vaccine development pipeline. Increased coordination and adoption of a more holistic view to vaccine development will be required to ensure more rapid progress in the years ahead.

Vaccine and vaccination as a part of human life: In view of COVID-19

Background

Vaccination created a great breakthrough toward the improvement to the global health. The development of vaccines and their use made a substantial decrease and control in infectious diseases. The abundance and emergence of new vaccines has facilitated targeting populations to alleviate and eliminate contagious pathogens from their innate reservoir. However, along with the infections like malaria and HIV, effective immunization remains obscure and imparts a great challenge to science.

Purpose and scope

The novel Corona virus SARS‐CoV‐2 is the reason for the 2019 COVID‐19 pandemic in the human global population, in the first half of 2019. The need for establishing a protected and compelling COVID‐19 immunization is a global prerequisite to end this pandemic.

Summary and conclusion

The different vaccine technologies like inactivation, attenuation, nucleic acid, viral vector, subunit, and viral particle based techniques are employed to develop a safe and highly efficient vaccine. The progress in vaccine development for SARS‐CoV2 is much faster in the history of science. Even though there exist of lot of limitations, continuous efforts has put forward so as to develop highly competent and effective vaccine for many human and animal linked diseases due to its unlimited prospective. This review article focuses on the historical outlook and the development of the vaccine as it is a crucial area of research where the life of the human is saved from various potential diseases.

Cost-effectiveness analysis of an intervention project engaging Traditional and Religious Leaders to improve uptake of childhood immunization in southern Nigeria

Vaccination is a cost-effective public health intervention, yet evidence abounds that vaccination uptake is still poor in many low- and middle-income countries. Traditional and Religious Leaders play a substantial role in improving the uptake of health services such as immunization. However, there is paucity of evidence on the cost-effectiveness of using such strategies. This study aimed to assess the cost-effectiveness of using a multi-faceted intervention that included traditional and religious leaders for community engagement to improve uptake of routine immunisation services in communities in Cross River State, Southern Nigeria. The target population for the intervention was traditional and religious leaders in randomly selected communities in Cross River State. The impact of the intervention on the uptake of routine vaccination among children 0 to 23 months was assessed using a cluster randomized trials. Outcome assessments were performed at the end of the project (36 months).The cost of the intervention was obtained from the accounting records for expenditures incurred in the course of implementing the intervention. Costs were assessed from the health provider perspective. The cost-effectiveness analysis showed that the incremental cost of the initial implementation of the intervention was US$19,357and that the incremental effect was 323 measles cases averted, resulting in an incremental cost-effectiveness ratio (ICER) of US$60/measles case averted. However, for subsequent scale-up of the interventions to new areas not requiring a repeat expenditure of some of the initial capital expenditure the ICER was estimated to be US$34 per measles case averted. Involving the traditional and religious leaders in vaccination is a cost-effective strategy for improving the uptake of childhood routine vaccinations.

Discrepancies and Similarities in Attitudes, Beliefs, and Familiarity with Vaccination Between Religious Studies and Science Students in Malaysia: A Comparison Study

Little is known about the impact of religion on vaccine receptivity in Malaysia. Improved vaccine uptake is positively reflected in the reduction of vaccine-preventable diseases. This study aimed to explore and compare the attitudes, religious beliefs, and familiarity regarding vaccination between the religious studies and science students. A survey-based cross-sectional study was conducted between a convenient sample of students (N = 300) of religious studies and applied sciences in Kuantan, Malaysia. A new, face- and content-validated questionnaire was used for data collection. A total of 206 students responded to the questionnaire, giving a response rate of 86.6%. Overall, participants demonstrated positive attitudes towards vaccination (n = 185, 89.9%). Only a minority of respondents expressed an opposition to vaccination (n = 21, 10.2%). Religious factors (permissibility) of vaccines (n = 12, 57.1%) and harm associated with the vaccine (n = 13, 61.9%) were the most common reasons for not supporting vaccination among the non-supporters. Most (n = 135, 65.5%) respondents agreed that vaccination is parallel with the Islamic concept of protecting life and preventing harm. Almost half of the respondents (n = 98, 47.6%) admit to declaring "Fatwa" to oblige parents to vaccinate their children. Religious beliefs and safety issues surrounding immunisation were reported as the major barriers for the support of immunisation. Well-designed programs are recommended to reshape the religious beliefs and convictions among students toward vaccination.

Altruism and vaccination intentions: Evidence from behavioral experiments

Vaccine hesitancy has been on the rise throughout the past two decades, especially in high income countries where existing pro-vaccination public health communication strategies have proven ineffective. We argue that appealing to other-regarding preferences is one way of improving the effectiveness of public health communication strategies. To test this argument, we assess how vaccination intentions are influenced by the presence of people who cannot vaccinate, such as the immunosuppressed, newborns or pregnant women, using a laboratory experiment where there is a passive player whose welfare depends on the decisions of other, active players. Results suggest that pro-vaccine messages targeting altruism can increase vaccination intentions by: (i) invoking past experiences of dependence and vulnerability; (ii) stressing cooperation as a social norm; and (iii) emphasizing the presence of vulnerable individuals in a given society.

Developing Adult Vaccination Ecosystem in India: Current Perspective and the Way Forward

Introduction

A high burden of vaccine-preventable diseases, increasing elderly population, immunosenescence, and emerging drug resistance emphasize the need for robust adult immunization in India. While immunization guidelines from various societies exist, there is inadequate implementation of the same.

Aim

We undertook this narrative review of the adult vaccination ecosystem in India to (i) gain insights into existing adult vaccination practices, (ii) identify barriers to adult vaccination and possible solutions, and (iii) improve collaboration between various stakeholders to help establish adult vaccination centers in the country.

Results

Besides the high cost and lack of insurance coverage, the lack of adult vaccination centers contributes to the low coverage of adult immunization.

Discussion

These challenges can be addressed through multiple approaches including community awareness and immunization programs, setting up mobile vaccination vans, patient/consumer education, and adequate training of healthcare providers. Successful implementation of these strategies requires active collaboration between the government, hospitals, different stakeholders, and policymakers.

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.

Health spending and vaccination coverage in low-income countries

INTRODUCTION

Routine immunisation is a cost-effective way to save lives and protect people from disease. Some low-income countries (LIC) achieved remarkable success in childhood immunisation. Yet, previous studies comparing the relationship between economic growth and health spending with vaccination coverage have been limited. We investigated these relationships among LIC to understand what financial changes lead to childhood immunisation changes.

METHODS

We identified which financial indicators were significant predictors of vaccination coverage in LIC by fitting regression models for several vaccines, controlling for population density, land area and female years of education. We then identified LIC with high vaccination coverage (LIC+) and compared their economic and health spending trends with other LIC (LIC-) and lower-middle income countries. We used cross-country multi-year regressions with mixed-effects to test financial indicators' rate of change. We conducted statistical tests to verify if financial trends of LIC+ were significantly different from LIC-.

RESULTS

During 2014-2018, gross domestic product per capita (p=0.67-0.95, range given by tests with different vaccines), total/private health spending per capita (p=0.57-0.97, p=0.32-0.57) and aggregated development assistance for health (DAH) per capita (p=0.38-0.86) were not significant predictors of vaccination coverage in LIC. Government health spending per capita (p=0.022-0.073) and total/government spending per birth on routine immunisation vaccines (p=0.0007-0.029, p=0.016-0.052) were significant positive predictors of vaccination coverage. From 2000 to 2016, LIC+ increased government health spending per capita by US$0.30 per year, while LIC- decreased by US$0.16 (significant difference, p<0.0001). From 2006 to 2017, LIC+ increased government spending per birth on routine immunisation vaccines by US$0.22 per year, while LIC- increased by US$0.10 (p<0.0093).

CONCLUSION

Vaccination coverage success of some LIC was not explained by economic development, total health spending nor aggregated DAH. Vaccination coverage success of LIC+ was associated with increasing government health spending particularly in routine immunisation vaccines.

Prophylactic Cancer Vaccines Engineered to Elicit Specific Adaptive Immune Response

Vaccines have been used to prevent and eradicate different diseases for over 200 years, and new vaccine technologies have the potential to prevent many common illnesses. Cancer, despite many advances in therapeutics, is still the second leading causes of death in the United States. Prophylactic, or preventative, cancer vaccines have the potential to reduce cancer prevalence by initiating a specific immune response that will target cancer before it can develop. Cancer vaccines can include many different components, such as peptides and carbohydrates, and be fabricated for delivery using a variety of means including through incorporation of stabilizing chemicals like polyethylene glycol (PEG) and pan-DR helper T-lymphocyte epitope (PADRE), fusion with antigen-presenting cells (APCs), microneedle patches, and liposomal encapsulation. There are currently five cancer vaccines used in the clinic, protecting against either human papillomavirus (HPV) or hepatitis B virus (HBV), and preventing several different types of cancer including cervical and oral cancer. Prophylactic cancer vaccines can promote three different types of adaptive responses: humoral (B cell, or antibody-mediated), cellular (T cell) or a combination of the two types. Each vaccine has its advantages and challenges at eliciting an adaptive immune response, but these prophylactic cancer vaccines in development have the potential to prevent or delay tumor development, and reduce the incidence of many common cancers.

Evidence-informed vaccination decision-making in countries: Progress, challenges and opportunities

Countries face an increasingly complex vaccination landscape. As well as ever-changing infectious disease epidemiology, the number and diversity of vaccine-preventable diseases, vaccine products, and vaccine technologies continue to increase. To ensure that vaccination decision-making is transparent, country-owned and informed by sound scientific evidence, many countries have established national immunization technical advisory groups (NITAGs) to provide independent expert advice. The past decade has seen substantial growth in NITAG numbers and functionality, and there is now a need to consolidate this progress, by further capacity building, to ensure that NITAGs are responsive to the changing face of immunization over the next decade.

Productivity loss/gain in cost-effectiveness analyses for vaccines: a systematic review

Introduction: The kinds of costs included in cost-effectiveness analyses (CEAs) for vaccines, such as direct medical costs and indirect costs, may affect their outcomes. While some guidelines recommend inclusion of costs associated with productivity losses/gains, very little guidance is provided about the productivity elements to include and their calculation approach.Areas covered: We conducted a systematic review of CEAs for vaccines and vaccine programs published between 1 January 2010 and 19 November 2019 that included productivity costs using Medline, Embase, and the Cochrane Library. The kind of productivity elements included their calculation approach, and the impact of their inclusion on cost-effectiveness are summarized. Among 88 studies identified, productivity elements included were reported for 71 studies (81%) with absenteeism being the most commonly included element. Only 24 studies (27%) reported the approach used to calculate productivity costs (human capital vs. friction approach). Most studies (81%) reported a more favorable cost-effectiveness with the inclusion of productivity losses/gains.Expert opinion: Inclusion of productivity losses/gains for CEAs for vaccines has resulted in more favorable cost-effectiveness based on the studies reviewed. However, clearer guidance on the productivity elements to include by disease area and more transparency on the calculation method used may be needed.

Estimating the health impact of vaccination against ten pathogens in 98 low-income and middle-income countries from 2000 to 2030: a modelling study

BACKGROUND

The past two decades have seen expansion of childhood vaccination programmes in low-income and middle-income countries (LMICs). We quantify the health impact of these programmes by estimating the deaths and disability-adjusted life-years (DALYs) averted by vaccination against ten pathogens in 98 LMICs between 2000 and 2030.

METHODS

16 independent research groups provided model-based disease burden estimates under a range of vaccination coverage scenarios for ten pathogens: hepatitis B virus, Haemophilus influenzae type B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, Streptococcus pneumoniae, rotavirus, rubella, and yellow fever. Using standardised demographic data and vaccine coverage, the impact of vaccination programmes was determined by comparing model estimates from a no-vaccination counterfactual scenario with those from a reported and projected vaccination scenario. We present deaths and DALYs averted between 2000 and 2030 by calendar year and by annual birth cohort.

FINDINGS

We estimate that vaccination of the ten selected pathogens will have averted 69 million (95% credible interval 52-88) deaths between 2000 and 2030, of which 37 million (30-48) were averted between 2000 and 2019. From 2000 to 2019, this represents a 45% (36-58) reduction in deaths compared with the counterfactual scenario of no vaccination. Most of this impact is concentrated in a reduction in mortality among children younger than 5 years (57% reduction [52-66]), most notably from measles. Over the lifetime of birth cohorts born between 2000 and 2030, we predict that 120 million (93-150) deaths will be averted by vaccination, of which 58 million (39-76) are due to measles vaccination and 38 million (25-52) are due to hepatitis B vaccination. We estimate that increases in vaccine coverage and introductions of additional vaccines will result in a 72% (59-81) reduction in lifetime mortality in the 2019 birth cohort.

INTERPRETATION

Increases in vaccine coverage and the introduction of new vaccines into LMICs have had a major impact in reducing mortality. These public health gains are predicted to increase in coming decades if progress in increasing coverage is sustained.

FUNDING

Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation.

Vaccine storage and distribution between expanded program on immunization and medical store department in Tanzania: a cost-minimization analysis

BACKGROUND

In 2016, the Tanzanian government shifted the vaccine supply chain responsibilities from the Medical Store Department (MSD) to the Expanded Program on Immunization (EPI) to reduce costs. However, cost estimates that informed the decision were based on invoice value of vaccines and related supplies, rather than a proper economic evaluation study. Therefore, this study aims to compare the actual storage and distribution costs of vaccines and related supplies between MSD to EPI.

METHOD

Micro-costing approach was used to estimate resource use at MSD and EPI for the year 2018. Data were collected through a review of documents, warehouse databases, and interviews with key staff at MSD and EPI. We included both capital and recurrent costs. Microsoft Excel® was used for analysis with input data from the UNICEF forecasting tool, WHOs vaccine volume and capacity estimation tool, diesel generator calculator, and supply chain service fee estimator version 1.02.

RESULTS

The total vaccine storage and distribution costs were estimated to be USD 1,996,286 at MSD and USD 543,648 at EPI. Distribution and program management costs represented 41% (USD 819,288) and 38% (USD 762,968) of the total costs at MSD, while storage and distribution costs represented 43% (USD 234,423) and 34% (USD 184,620) of the total costs at EPI, respectively. The cost drivers at MSD were fuel and transport (21%), receiving and dispatch (19%) and, program management personnel cost (14%), while at EPI were storage space (20%), program management personnel cost (18%) and fuel and transport (15%).

CONCLUSION

The storage and distribution of vaccines in Tanzania via the EPI reduced the vaccine supply chain cost to about 27% of the program costs at MSD.

Effects of the Coronavirus disease 2019 pandemic on routine pediatric immunization coverage rates at the main University Hospital in Saudi Arabia

OBJECTIVES

To investigate whether the coronavirus disease-2019 pandemic has had any effects on pediatric vaccination rates at the main university hospital in Saudi Arabia.

METHODS

A retrospective study conducted at King Saud University Medical City, Riyadh, Saudi Arabia using electronic health records. The vaccination statuses of all children who were scheduled for vaccinations at birth and at 2, 4, 6, 9, and 12 months during March, April and May between 2017 and 2020 were included in the study with total sample of 15,870 children, and comparisons between the cohorts were performed.

RESULTS

All vaccination visits during April and May 2020 were below the lower extremes except for the birth vaccinations. In March, April, and May 2020 there were respective drops in vaccination visits of 49.93%, 71.90% and 68.48% compared with the mean numbers of vaccination visits during the same months from 2017 to 2019. In comparisons of mean numbers of visits from March 2017 to May 2019 and March to May in 2020, the respective reductions in visits for birth and 2, 4, 6, 9 and 12-month vaccinations were 16.5%, 80.5%, 74.7%, 72.9%, 80.0% and 74.1%.

CONCLUSIONS

The huge impact of the coronavirus disease-2019 pandemic on childhood vaccinations will require urgent vaccination recovery plans with innovative approaches and future action plans to maintain vaccination coverage during any subsequent pandemics.

Routine childhood immunisation during the COVID-19 pandemic in Africa: a benefit-risk analysis of health benefits versus excess risk of SARS-CoV-2 infection

BACKGROUND

National immunisation programmes globally are at risk of suspension due to the severe health system constraints and physical distancing measures in place to mitigate the ongoing COVID-19 pandemic. We aimed to compare the health benefits of sustaining routine childhood immunisation in Africa with the risk of acquiring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through visiting routine vaccination service delivery points.

METHODS

We considered a high-impact scenario and a low-impact scenario to approximate the child deaths that could be caused by immunisation coverage reductions during COVID-19 outbreaks. In the high-impact scenario, we used previously reported country-specific child mortality impact estimates of childhood immunisation for diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b, Streptococcus pneumoniae, rotavirus, measles, meningitis A, rubella, and yellow fever to approximate the future deaths averted before 5 years of age by routine childhood vaccination during a 6-month COVID-19 risk period without catch-up campaigns. In the low-impact scenario, we approximated the health benefits of sustaining routine childhood immunisation on only the child deaths averted from measles outbreaks during the COVID-19 risk period. We assumed that contact-reducing interventions flattened the outbreak curve during the COVID-19 risk period, that 60% of the population will have been infected by the end of that period, that children can be infected by either vaccinators or during transport, and that upon child infection the whole household will be infected. Country-specific household age structure estimates and age-dependent infection-fatality rates were applied to calculate the number of deaths attributable to the vaccination clinic visits. We present benefit-risk ratios for routine childhood immunisation, with 95% uncertainty intervals (UIs) from a probabilistic sensitivity analysis.

FINDINGS

In the high-impact scenario, for every one excess COVID-19 death attributable to SARS-CoV-2 infections acquired during routine vaccination clinic visits, 84 (95% UI 14-267) deaths in children could be prevented by sustaining routine childhood immunisation in Africa. The benefit-risk ratio for the vaccinated children is 85 000 (4900-546 000), for their siblings (<20 years) is 75 000 (4400-483 000), for their parents or adult carers (aged 20-60 years) is 769 (148-2700), and for older adults (>60 years) is 96 (14-307). In the low-impact scenario that approximates the health benefits to only the child deaths averted from measles outbreaks, the benefit-risk ratio to the households of vaccinated children is 3 (0-10); if the risk to only the vaccinated children is considered, the benefit-risk ratio is 3000 (182-21 000).

INTERPRETATION

The deaths prevented by sustaining routine childhood immunisation in Africa outweigh the excess risk of COVID-19 deaths associated with vaccination clinic visits, especially for the vaccinated children. Routine childhood immunisation should be sustained in Africa as much as possible, while considering other factors such as logistical constraints, staff shortages, and reallocation of resources during the COVID-19 pandemic.

FUNDING

Gavi, the Vaccine Alliance; Bill & Melinda Gates Foundation.