Cost-effectiveness of providing measles vaccination to all children in Guinea-Bissau

Cost-Effectiveness Analysis of Routine Outreach and Catch-Up Campaign Strategies for Measles, Mumps, and Rubella Vaccination in Chuuk, Federated States of Micronesia

OBJECTIVE

The Federated States of Micronesia (FSM) experience periodic outbreaks of vaccine-preventable diseases. Our objective was to assess the cost-effectiveness of routine outreach and catch-up campaign strategies for increasing vaccination coverage for the measles, mumps, and rubella (MMR) vaccine among children aged 12 months through 6 years in Chuuk, FSM.

METHODS

We used a cost-effectiveness model to assess 4 MMR vaccination strategies from a public health perspective: routine outreach conducted 4 times per year (quarterly routine outreach), routine outreach conducted 2 times per year (biannual routine outreach), catch-up campaigns conducted once per year (annual catch-up campaign), and catch-up campaigns conducted every 2 years with quarterly routine outreach in non-catch-up campaign years (status quo). We calculated costs and outcomes during a 5-year model horizon and summarized results as incremental cost-effectiveness ratios. We analyzed the following public health outcomes: additional protected person-month (PPM), doses administered and protected people (ie, a child who completed a 2-dose MMR series). We conducted 1-way sensitivity analyses to evaluate the stability of incremental cost-effectiveness ratios and to identify influential model inputs.

RESULTS

Among the 4 MMR vaccination strategies, quarterly routine outreach was the most effective and most expensive strategy, and biannual routine outreach was the least expensive and least effective strategy. Quarterly routine outreach (vs status quo) yielded approximately an additional 7001 PPMs and 132 vaccine doses administered, with incremental costs of about $4 per PPM, $193 per dose administered, and $123 per protected person.

CONCLUSION

Routine outreach and catch-up campaign vaccination strategies can be important interventions to improve health in Chuuk, FSM. More frequent routine outreach events could improve MMR coverage and reduce the likelihood of outbreaks of vaccine-preventable diseases such as measles and mumps.

Health system barriers to the first dose of measles immunization in Ethiopia: a qualitative study

BACKGROUND

Ethiopia has made considerable progress toward measles elimination. Despite ongoing efforts, the country remains among those with the highest number of children missing their initial dose of measles vaccine, and the disease continues to be a public health emergency. The barriers within the health system that hinder the first dose of measles immunization have not been thoroughly investigated. This study aims to identify these barriers within the Ethiopian context.

METHODS

Qualitative research, using purposive expert sampling to select key informants from health organizations in Addis Ababa, Ethiopia was employed. We conducted in-depth face-to-face interviews using a semi-structured interview guide. A thematic analysis based on the World Health Organization's health systems building blocks framework was conducted.

RESULTS

The study uncovered substantial health system barriers to the uptake of the first dose of the measles vaccine in Ethiopia. These barriers include; restricted availability of immunization services, vaccine stockouts, shortage of cold chain technologies, data inaccuracy resulting from deliberate data falsification or accidental manipulation of data, as well as data incompleteness.

CONCLUSION

Our research highlighted significant health system barriers to MCV1 immunization, contributing to unmet EPI targets in Ethiopia. Our results suggest that to accelerate the country towards measles elimination, there is an urgent need to improve the health systems components such as service delivery, information systems, as well as access to vaccine and cold chain technologies.

Inequalities in child immunization coverage: potential lessons from the Guinea-Bissau case

Immunization is one of the main interventions responsible for the decline in under-5 mortality. This study aimed to assess full immunization coverage trends and related inequalities, according to wealth, area of residence, subnational regions, and maternal schooling level in Guinea-Bissau. Data from the 2006, 2014, and 2018 Guinea-Bissau Multiple Indicator Cluster Surveys (MICS) were analyzed. The slope index of inequality (SII) was estimated by logistic regression for wealth quintiles and maternal schooling level as a measure of absolute inequality. A linear regression model with variance-weighted least squares was used to estimate the annual change of immunization indicators at the national level and for the extremes of wealth, maternal schooling level, and urban-rural areas. Full immunization coverage increased by 1.8p.p./year (95%CI: 1.3; 2.3) over the studied period. Poorer children and children born to uneducated mothers were the most disadvantaged groups. Over the years, wealth inequality decreased and urban-rural inequalities were practically extinguished. In contrast, inequality of maternal schooling level remained unchanged, thus, the highest immunization coverage was among children born to the most educated women. This study shows persistent low immunization coverage and related inequalities in Guinea-Bissau, especially according to maternal schooling level. These findings reinforce the need to adopt equity as a main principle in the development of public health policies to appropriately reduce gaps in immunization and truly leave no one behind in Guinea-Bissau and beyond.

One vaccine to counter many diseases? Modeling the economics of oral polio vaccine against child mortality and COVID-19

Introduction

Recent reviews summarize evidence that some vaccines have heterologous or non-specific effects (NSE), potentially offering protection against multiple pathogens. Numerous economic evaluations examine vaccines' pathogen-specific effects, but less than a handful focus on NSE. This paper addresses that gap by reporting economic evaluations of the NSE of oral polio vaccine (OPV) against under-five mortality and COVID-19.

Materials and methods

We studied two settings: (1) reducing child mortality in a high-mortality setting (Guinea-Bissau) and (2) preventing COVID-19 in India. In the former, the intervention involves three annual campaigns in which children receive OPV incremental to routine immunization. In the latter, a susceptible-exposed-infectious-recovered model was developed to estimate the population benefits of two scenarios, in which OPV would be co-administered alongside COVID-19 vaccines. Incremental cost-effectiveness and benefit-cost ratios were modeled for ranges of intervention effectiveness estimates to supplement the headline numbers and account for heterogeneity and uncertainty.

Results

For child mortality, headline cost-effectiveness was $650 per child death averted. For COVID-19, assuming OPV had 20% effectiveness, incremental cost per death averted was $23,000-65,000 if it were administered simultaneously with a COVID-19 vaccine <200 days into a wave of the epidemic. If the COVID-19 vaccine availability were delayed, the cost per averted death would decrease to $2600-6100. Estimated benefit-to-cost ratios vary but are consistently high.

Discussion

Economic evaluation suggests the potential of OPV to efficiently reduce child mortality in high mortality environments. Likewise, within a broad range of assumed effect sizes, OPV (or another vaccine with NSE) could play an economically attractive role against COVID-19 in countries facing COVID-19 vaccine delays.

Funding

The contribution by DTJ was supported through grants from Trond Mohn Foundation (BFS2019MT02) and Norad (RAF-18/0009) through the Bergen Center for Ethics and Priority Setting.

Health effects of utilising hospital contacts to provide measles vaccination to children 9-59 months-a randomised controlled trial in Guinea-Bissau

BACKGROUND

Measles vaccination coverage in Guinea-Bissau is low; fewer than 80% of children are currently measles vaccinated before 12 months of age. The low coverage hampers control of measles. Furthermore, accumulating evidence indicates that measles vaccine has beneficial non-specific effects, strengthening the resistance towards other infections. Thus, even if children are not exposed to measles virus, measles-unvaccinated children may be worse off. To increase vaccination coverage, WHO recommends that contacts with the health system for mild illness are utilised to vaccinate. Currently, in Guinea-Bissau, curative health system contacts are not utilised.

METHODS

Bandim Health Project registers out-patient consultations and admissions at the paediatric ward of the National Hospital in Guinea-Bissau. Measles-unvaccinated children aged 9-59 months consulting for milder illness or being discharged from the paediatric ward will be invited to participate in a randomised trial. Among 5400 children, randomised 1:1 to receive standard measles vaccine or a saline placebo, we will test the hypothesis that providing a measles vaccine at discharge lowers the risk of admission/mortality (composite outcome) during the subsequent 6 months by 25%. All enrolled children are followed through the Bandim Health Project registration system and through telephone follow-up. The first 1000 enrolled children are furthermore followed through interviews on days 2, 4, 7 and 14 after enrolment.

DISCUSSION

Utilising missed vaccination opportunities can increase vaccination coverage and may improve child health. However, without further evidence for the safety and potential benefits of measles vaccination, these curative contacts are unlikely to be used for vaccination in Guinea-Bissau.

TRIAL REGISTRATION

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Health economic analyses of secondary vaccine effects: a systematic review and policy insights

INTRODUCTION

: Numerous analyses demonstrate substantial health economic impacts of primary vaccine effects (preventing or mitigating clinical manifestations of the diseases they target), but vaccines may also be associated with secondary effects, previously known as non-specific, heterologous, or off-target effects.

AREAS COVERED

: We define key concepts to distinguish primary and secondary vaccine effects for health economic analyses, summarized terminology used in different fields, and perform a systematic review of health economic analyses focused on secondary vaccine effects (SVEs).

EXPERT OPINION

: Health economists integrate evidence from multiple fields, which often use incomplete or inconsistent definitions. Like regulators and policy makers, health economists require high-quality evidence of specific effects. Consistent with the limited evidence on mechanisms of action for SVEs, the associated health economic literature remains highly limited, with 4 studies identified by our systematic review. The lack of specific and well-controlled evidence that supports quantification of specific SVEs limits the consideration of these effects in vaccine research, development, regulatory, and recommendation decisions and health economic analyses.

Should countries switch to using five- or ten-dose rotavirus vaccines now that they are available?

Introduction:

Single-dose rotavirus vaccines, which are used by a majority of countries, are some of the largest-sized vaccines in immunization programs, and have been shown to constrain supply chains and cause bottlenecks. Efforts have been made to reduce the size of the single-dose vaccines; however, with two-dose, five-dose and ten-dose options available, the question then is whether using multi-dose instead of single-dose rotavirus vaccines will improve vaccine availability.

Methods:

We used HERMES-generated simulation models of the vaccine supply chains of the Republic of Benin, Mozambique, and Bihar, a state in India, to evaluate the operational and economic impact of implementing each of the nine different rotavirus vaccine presentations.

Results:

Among single-dose rotavirus vaccines, using Rotarix RV1 MMP (multi-monodose presentation) led to the highest rotavirus vaccine availability (49–80%) and total vaccine availability (56–79%), and decreased total costs per dose administered ($0.02-$0.10) compared to using any other single-dose rotavirus vaccine. Using two-dose ROTASIIL decreased rotavirus vaccine availability by 3–6% across each supply chain compared to Rotarix RV1 MMP, the smallest single-dose vaccine. Using a five-dose rotavirus vaccine improved rotavirus vaccine availability (52–92%) and total vaccine availability (60–85%) compared to single-dose and two-dose vaccines. Further, using the ten-dose vaccine led to the highest rotavirus vaccine availability compared to all other rotavirus vaccines in both Benin and Bihar.

Conclusion:

Our results show that countries that implement five-dose or ten-dose rotavirus vaccines consistently reduce cold chain constraints and achieve higher rotavirus and total vaccine availability compared to using either single-dose or two-dose rotavirus vaccines.

Old vaccines for new infections: Exploiting innate immunity to control COVID-19 and prevent future pandemics

The COVID-19 pandemic triggered an unparalleled pursuit of vaccines to induce specific adaptive immunity, based on virus-neutralizing antibodies and T cell responses. Although several vaccines have been developed just a year after SARS-CoV-2 emerged in late 2019, global deployment will take months or even years. Meanwhile, the virus continues to take a severe toll on human life and exact substantial economic costs. Innate immunity is fundamental to mammalian host defense capacity to combat infections. Innate immune responses, triggered by a family of pattern recognition receptors, induce interferons and other cytokines and activate both myeloid and lymphoid immune cells to provide protection against a wide range of pathogens. Epidemiological and biological evidence suggests that the live-attenuated vaccines (LAV) targeting tuberculosis, measles, and polio induce protective innate immunity by a newly described form of immunological memory termed "trained immunity." An LAV designed to induce adaptive immunity targeting a particular pathogen may also induce innate immunity that mitigates other infectious diseases, including COVID-19, as well as future pandemic threats. Deployment of existing LAVs early in pandemics could complement the development of specific vaccines, bridging the protection gap until specific vaccines arrive. The broad protection induced by LAVs would not be compromised by potential antigenic drift (immune escape) that can render viruses resistant to specific vaccines. LAVs might offer an essential tool to "bend the pandemic curve," averting the exhaustion of public health resources and preventing needless deaths and may also have therapeutic benefits if used for postexposure prophylaxis of disease.

Projected impact and cost-effectiveness of community-based versus targeted azithromycin administration strategies for reducing child mortality in sub-Saharan Africa

BACKGROUND

Trials of mass drug administration (MDA) of azithromycin (AZM) report reductions in child mortality in sub-Saharan Africa (SSA). AZM targeted to high-risk children may preserve benefit while minimizing antibiotic exposure. We modeled the cost-effectiveness of MDA to children 1-59 months of age, MDA to children 1-5 months of age, AZM administered at hospital discharge, and the combination of MDA and post-discharge AZM.

METHODS AND FINDINGS

Models employed a payer perspective with a 1-year time horizon. Cost-effectiveness was presented as cost per DALY averted and death averted, with probabilistic sensitivity analyses. The model included parameters for macrolide resistance, adverse events, hospitalization, and mortality sourced from published data. Assuming a base-case 1.64% mortality risk among children 1-59 months old, 3.1% among children 1-5 months old, 4.4% mortality risk post-discharge, and 13.5% mortality reduction per trial data, post-discharge AZM would avert ~45,000 deaths, at a cost of $2.84/DALY (95% uncertainty interval [UI]: 1.71-5.57) averted. MDA to only children 1-5 months old would avert ~186,000 deaths at a cost of $4.89/DALY averted (95% UI: 2.88-11.42), MDA to all under-5 children would avert ~267,000 deaths a cost of $14.26/DALY averted (95% UI: 8.72-27.08). Cost-effectiveness decreased with presumed diminished efficacy due to macrolide resistance.

CONCLUSIONS

Targeting AZM to children at highest risk of death may be an antibiotic-sparing and cost-effective, or even cost-saving, strategy to reduce child mortality. However, targeted AZM averts fewer absolute deaths and may not reach all children who would benefit. Any AZM administration decision must consider implications for antibiotic resistance.

Systematic review of the costs and effectiveness of interventions to increase infant vaccination coverage in low- and middle-income countries

Background

In recent years, several large studies have assessed the costs of national infant immunization programs, and the results of these studies are used to support planning and budgeting in low- and middle-income countries. However, few studies have addressed the costs and cost-effectiveness of interventions to improve immunization coverage, despite this being a major focus of policy attention. Without this information, countries and international stakeholders have little objective evidence on the efficiency of competing interventions for improving coverage.

Methods

We conducted a systematic literature review on the costs and cost-effectiveness of interventions to improve immunization coverage in low- and middle-income countries, including both published and unpublished reports. We evaluated the quality of included studies and extracted data on costs and incremental coverage. Where possible, we calculated incremental cost-effectiveness ratios (ICERs) to describe the efficiency of each intervention in increasing coverage.

Results

A total of 14 out of 41 full text articles reviewed met criteria for inclusion in the final review. Interventions for increasing immunization coverage included demand generation, modified delivery approaches, cash transfer programs, health systems strengthening, and novel technology usage. We observed substantial heterogeneity in costing methods and incompleteness of cost and coverage reporting. Most studies reported increases in coverage following the interventions, with coverage increasing by an average of 23 percentage points post-intervention across studies. ICERs ranged from $0.66 to $161.95 per child vaccinated in 2017 USD. We did not conduct a meta-analysis given the small number of estimates and variety of interventions included.

Conclusions

There is little quantitative evidence on the costs and cost-effectiveness of interventions for improving immunization coverage, despite this being a major objective for national immunization programs. Efforts to improve the level of costing evidence—such as by integrating cost analysis within implementation studies and trials of immunization scale up—could allow programs to better allocate resources for coverage improvement. Greater adoption of standardized cost reporting methods would also enable the synthesis and use of cost data.

Electronic supplementary material

The online version of this article (10.1186/s12913-019-4468-4) contains supplementary material, which is available to authorized users.

A Systematic Review of the Incremental Costs of Implementing a New Vaccine in the Expanded Program of Immunization in Sub-Saharan Africa

Background. The World Health Organization is planning a pilot introduction of a new malaria vaccine in three sub-Saharan African countries. To inform considerations about including a new vaccine in the vaccination program of those and other countries, estimates from the scientific literature of the incremental costs of doing so are important. Methods. A systematic review of scientific studies reporting the costs of recent vaccine programs in sub-Saharan countries was performed. The focus was to obtain from each study an estimate of the cost per dose of vaccine administered excluding the acquisition cost of the vaccine and wastage. Studies published between 2000 and 2018 and indexed on PubMed could be included and results were standardized to 2015 US dollars (US$). Results. After successive screening of 2119 titles, and 941 abstracts, 58 studies with 80 data points (combinations of country, vaccine type, and vaccination approach-routine v. campaign) were retained. Most studies used the so-called ingredients approach as costing method combining field data collection with documented unit prices per cost item. The categorization of cost items and the extent of detailed reporting varied widely. Across the studies, the mean and median cost per dose administered was US$1.68 and US$0.88 with an interquartile range of US$0.54 to US$2.31. Routine vaccination was more costly than campaigns, with mean cost per dose of US$1.99 and US$0.88, respectively. Conclusion. Across the studies, there was huge variation in the cost per dose delivered, between and within countries, even in studies using consistent data collection tools and analysis methods, and including many health facilities. For planning purposes, the interquartile range of US$0.54 to US$2.31 may be a sufficiently precise estimate.

Cohort profile : Bandim Health Project's (BHP) rural Health and Demographic Surveillance System (HDSS)-a nationally representative HDSS in Guinea-Bissau

PURPOSE

Bandim Health Project (BHP) monitors health and survival of women and children in a nationally representative rural Health and Demographic Surveillance System (HDSS) in Guinea-Bissau. The HDSS was set up in 1989-1990 to collect data on health interventions and child mortality.

PARTICIPANTS

The HDSS covers 182 randomly selected clusters across the whole country. The cohort is open, and women and children enter the cohort, when they move into the selected clusters, and leave the cohort, when they move out or die, or when children reach 5 years of age. Data are collected through biannual or more frequent household visits. At all village visits, information on pregnancies, vital status, vaccination status, arm circumference, use of bed nets and other basic information is collected for women and children. Today, more than 25 000 women and 23 000 children below the age of 5 years are under surveillance.

FINDINGS TO DATE

Research from the BHP has given rise to the hypothesis that vaccines, in addition to their targeted effects, have important non-specific effects altering the susceptibility to other infections. Initially, it was observed that mortality among children vaccinated with the live BCG or measles vaccines was much lower than the mortality among unvaccinated children, a difference, which could not be explained by prevention of tuberculosis and measles infections. In contrast, mortality tended to be higher for children who had received the non-live Diphtheria-Tetanus-Pertussis vaccine compared with children who had not received this vaccine. Since the effect differed for the different vaccines, no bias explained the contrasting findings.

FUTURE PLANS

New health interventions are introduced with little assessment of real-life effects. Through the HDSS, we can describe both the implementation of interventions (eg, the vaccination programme) and their effects. Furthermore, the intensive follow-up allows the implementation of randomised trials testing potential better vaccination programmes.

Modeling the economic impact of different vial-opening thresholds for measles-containing vaccines

INTRODUCTION

The lack of specific policies on how many children must be present at a vaccinating location before a healthcare worker can open a measles-containing vaccine (MCV) - i.e. the vial-opening threshold - has led to inconsistent practices, which can have wide-ranging systems effects.

METHODS

Using HERMES-generated simulation models of the routine immunization supply chains of Benin, Mozambique and Niger, we evaluated the impact of different vial-opening thresholds (none, 30% of doses must be used, 60%) and MCV presentations (10-dose, 5-dose) on each supply chain. We linked these outputs to a clinical- and economic-outcomes model which translated the change in vaccine availability to associated infections, medical costs, and DALYs. We calculated the economic impact of each policy from the health system perspective.

RESULTS

The vial-opening threshold that maximizes vaccine availability while minimizing costs varies between individual countries. In Benin (median session size = 5), implementing a 30% vial-opening threshold and tailoring distribution of 10-dose and 5-dose MCVs to clinics based on session size is the most cost-effective policy, preventing 671 DALYs ($471/DALY averted) compared to baseline (no threshold, 10-dose MCVs). In Niger (median MCV session size = 9), setting a 60% vial-opening threshold and tailoring MCV presentations is the most cost-effective policy, preventing 2897 DALYs ($16.05/ DALY averted). In Mozambique (median session size = 3), setting a 30% vial-opening threshold using 10-dose MCVs is the only beneficial policy compared to baseline, preventing 3081 DALYs ($85.98/DALY averted). Across all three countries, however, a 30% vial-opening threshold using 10-dose MCVs everywhere is the only MCV threshold that consistently benefits each system compared to baseline.

CONCLUSION

While the ideal vial-opening threshold policy for MCV varies by supply chain, implementing a 30% vial-opening threshold for 10-dose MCVs benefits each system by improving overall vaccine availability and reducing associated medical costs and DALYs compared to no threshold.

Non-live pentavalent vaccines after live measles vaccine may increase mortality

Live measles vaccine (MV) may have beneficial off-target/non-specific effects (NSEs) reducing child mortality beyond prevention of measles infection. In contrast, the non-live pentavalent (Diphtheria-Tetanus-Pertussis-H. influenzae Type B-Hepatitis B) vaccine has no beneficial NSEs. The NSEs are strongest for the most recent vaccine. Hence, sequence of vaccination may affect survival. In Guinea-Bissau, we followed 7094 measles-vaccinated children prospectively from first home visit after 9 months (when MV is scheduled) to 5 years of age. We compared survival by sequence of MV and third Pentavalent vaccine (Penta3; scheduled at 3½ months) in Cox proportional-hazards models. Compared with being vaccinated in-sequence (Penta3-then-MV), having received out-of-sequence Penta3-after-MV before the visit was associated with an adjusted Hazard Ratio (aHR) of 1.19 (95%CI: 0.84-1.69); Receiving missing Penta doses on the visit date tended to be associated with higher mortality (aHR = 1.87 (0.96-3.65)) while not receiving missing doses of Penta was not (aHR = 0.93 (0.57-1.54)), test for interaction p = 0.09.