Cost-effectiveness analysis of changing from live oral poliovirus vaccine to inactivated poliovirus vaccine in Australia

Cost-effectiveness of various immunization schedules with inactivated Sabin strain polio vaccine in Hangzhou, China

Background

It is necessary to select suitable inactivated poliovirus vaccine(IPV) and live, attenuated oral poliovirus vaccine (OPV) sequential immunization programs and configure the corresponding health resources. An economic evaluation was conducted on the sequential procedures of Sabin strain-based IPV (sIPV) and bivalent OPV (bOPV) with different doses to verify whether a cost-effectiveness target can be achieved. This study aimed to evaluate the cost-effectiveness of different sIPV immunization schedules, which would provide convincing evidence to further change the poliovirus vaccine (PV) immunization strategies in China.

Methods

Five strategies were included in this analysis. Based on Strategy 0(S₀), the incremental cost (IC), incremental effect (IE), and incremental cost-effectiveness ratio (ICER) of the four different strategies (S₁/S₂/S₃/S₄) were calculated based on the perspective of the society. Seven cost items were included in this study. Results of field investigations and expert consultations were used to calculate these costs.

Results

The ICs of S₁/S₂/S₃/S₄ was Chinese Yuan (CNY) 30.77, 68.58, 103.82, and 219.82 million, respectively. The IE of vaccine-associated paralytic poliomyelitis (IE_VAPP) cases of S₁/S₂/S₃/S₄ were 0.22, 0.22, 0.22, and 0.11, respectively, while the IE of disability-adjusted life-years (IE_DALY) of S₁/S₂/S₃/S₄ were 8.98, 8.98, 8.98, and 4.49, respectively. The ICER_VAPP of S₁/S₂/S₃/S₄ gradually increased to CNY 13.99, 31.17, 47.19, and 199.83 million/VAPP, respectively. The ICER_DALY of S₁/S₂/S₃/S₄ also gradually increased to CNY 0.34, 0.76, 1.16, and 4.90 million/DALY, respectively.

Conclusion

ICER_VAPP and ICER_DALY were substantially higher for S₃ (four-sIPV) and S₄ (replacement of self-funded sIPV based on one-sIPV-three-bOPV). Two-sIPV-two-bOPV had a cost-effectiveness advantage, whereas S2/S3/S4 had no cost-effectiveness advantage.

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.

Cost-Effectiveness of Three Poliovirus Immunization Schedules in Shanghai, China

In Shanghai, China, a polio immunization schedule of four inactivated polio vaccines (IPV) has been implemented since 2020, replacing the schedules of a combination of two IPVs and two bivalent live attenuated oral polio vaccines (bOPV), and four trivalent live attenuated oral polio vaccines (tOPV). This study aimed to assess the cost-effectiveness of these three schedules in infants born in 2016, in preventing vaccine-associated paralytic poliomyelitis (VAPP). We performed a decision tree model and estimated incremental cost-effectiveness ratio (ICER). Compared to the four-tOPV schedule, the two-IPV-two-bOPV schedule averted 1.2 VAPP cases and 16.83 disability-adjusted life years (DALY) annually; while the four-IPV schedule averted 1.35 VAPP cases and 18.96 DALY annually. Consequently, ICER_VAPP and ICER_DALY were substantially high for two-IPV-two-bOPV (CNY 12.96 million and 0.93 million), and four-IPV (CNY 21.24 million and 1.52 million). Moreover, net monetary benefit of the two-IPV-two-bOPV and four-IPV schedules was highest when the cost of IPV was hypothesized to be less than CNY 23.75 or CNY 9.11, respectively, and willingness-to-pay was hypothesized as CNY 0.6 million in averting one VAPP-induced DALY. IPV-containing schedules are currently cost-ineffective in Shanghai. They may be cost-effective by reducing the prices of IPV, which may accelerate polio eradication in Chinese settings.

Thrombosis with Thrombocytopenia Syndrome (TTS) following AstraZeneca ChAdOx1 nCoV-19 (AZD1222) COVID-19 vaccination - A risk-benefit analysis for people < 60 years in Australia

The AstraZeneca ChAdOx1 nCoV-19 (AZD1222) vaccine is associated with Thrombosis with Thrombocytopenia Syndrome (TTS) in 3/100,000 vaccinations with high fatality rates reported in many countries. We conducted a risk-benefit analysis for Australians aged 18-59 years, comparing the risk of vaccination versus infection, and rate of TTS to other vaccines which prompted policy change following rare adverse events - rotavirus, smallpox and oral polio vaccines. COVID-19 deaths over 12 months range from 0 to 417 in current and future worst case scenarios. In the past 15 months 20 COVID-19 deaths occurred in people < 60 years compared to 890 deaths over 60 years. The estimated possible number of TTS cases is 347, with vaccine-related deaths ranging from 17 to 153if 80% of adults 18-59 years are vaccinated. The reported rate of TTS is in the same range as rare but serious adverse events associated with other vaccines that have been subject to policy change. In Australia, the potential risks of the AZD1222 vaccine in younger adults, who are at low risk of dying from COVID-19, may outweigh the benefits.

Review of poliovirus modeling performed from 2000 to 2019 to support global polio eradication

INTRODUCTION

Over the last 20 years (2000-2019) the partners of the Global Polio Eradication Initiative (GPEI) invested in the development and application of mathematical models of poliovirus transmission as well as economics, policy, and risk analyses of polio endgame risk management options, including policies related to poliovirus vaccine use during the polio endgame.

AREAS COVERED

This review provides a historical record of the polio studies published by the three modeling groups that primarily performed the bulk of this work. This review also systematically evaluates the polio transmission and health economic modeling papers published in English in peer-reviewed journals from 2000 to 2019, highlights differences in approaches and methods, shows the geographic coverage of the transmission modeling performed, identified common themes, and discusses instances of similar or conflicting insights or recommendations.

EXPERT OPINION

Polio modeling performed during the last 20 years substantially impacted polio vaccine choices, immunization policies, and the polio eradication pathway. As the polio endgame continues, national preferences for polio vaccine formulations and immunization strategies will likely continue to change. Future modeling will likely provide important insights about their cost-effectiveness and their relative benefits with respect to controlling polio and potentially achieving and maintaining eradication.

An economic analysis of poliovirus risk management policy options for 2013-2052

Background

The Global Polio Eradication Initiative plans for coordinated cessation of oral poliovirus vaccine (OPV) after interrupting all wild poliovirus (WPV) transmission, but many questions remain related to long-term poliovirus risk management policies.

Methods

We used an integrated dynamic poliovirus transmission and stochastic risk model to simulate possible futures and estimate the health and economic outcomes of maintaining the 2013 status quo of continued OPV use in most developing countries compared with OPV cessation policies with various assumptions about global inactivated poliovirus vaccine (IPV) adoption.

Results

Continued OPV use after global WPV eradication leads to continued high costs and/or high cases. Global OPV cessation comes with a high probability of at least one outbreak, which aggressive outbreak response can successfully control in most instances. A low but non-zero probability exists of uncontrolled outbreaks following a poliovirus reintroduction long after OPV cessation in a population in which IPV-alone cannot prevent poliovirus transmission. We estimate global incremental net benefits during 2013–2052 of approximately $16 billion (US$2013) for OPV cessation with at least one IPV routine immunization dose in all countries until 2024 compared to continued OPV use, although significant uncertainty remains associated with the frequency of exportations between populations and the implementation of long term risk management policies.

Conclusions

Global OPV cessation offers the possibility of large future health and economic benefits compared to continued OPV use. Long-term poliovirus risk management interventions matter (e.g., IPV use duration, outbreak response, containment, continued surveillance, stockpile size and contents, vaccine production site requirements, potential antiviral drugs, and potential safer vaccines) and require careful consideration. Risk management activities can help to ensure a low risk of uncontrolled outbreaks and preserve or further increase the positive net benefits of OPV cessation. Important uncertainties will require more research, including characterizing immunodeficient long-term poliovirus excretor risks, containment risks, and the kinetics of outbreaks and response in an unprecedented world without widespread live poliovirus exposure.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1112-8) contains supplementary material, which is available to authorized users.

An economic analysis of poliovirus risk management policy options for 2013-2052

BACKGROUND

The Global Polio Eradication Initiative plans for coordinated cessation of oral poliovirus vaccine (OPV) after interrupting all wild poliovirus (WPV) transmission, but many questions remain related to long-term poliovirus risk management policies.

METHODS

We used an integrated dynamic poliovirus transmission and stochastic risk model to simulate possible futures and estimate the health and economic outcomes of maintaining the 2013 status quo of continued OPV use in most developing countries compared with OPV cessation policies with various assumptions about global inactivated poliovirus vaccine (IPV) adoption.

RESULTS

Continued OPV use after global WPV eradication leads to continued high costs and/or high cases. Global OPV cessation comes with a high probability of at least one outbreak, which aggressive outbreak response can successfully control in most instances. A low but non-zero probability exists of uncontrolled outbreaks following a poliovirus reintroduction long after OPV cessation in a population in which IPV-alone cannot prevent poliovirus transmission. We estimate global incremental net benefits during 2013-2052 of approximately $16 billion (US$2013) for OPV cessation with at least one IPV routine immunization dose in all countries until 2024 compared to continued OPV use, although significant uncertainty remains associated with the frequency of exportations between populations and the implementation of long term risk management policies.

CONCLUSIONS

Global OPV cessation offers the possibility of large future health and economic benefits compared to continued OPV use. Long-term poliovirus risk management interventions matter (e.g., IPV use duration, outbreak response, containment, continued surveillance, stockpile size and contents, vaccine production site requirements, potential antiviral drugs, and potential safer vaccines) and require careful consideration. Risk management activities can help to ensure a low risk of uncontrolled outbreaks and preserve or further increase the positive net benefits of OPV cessation. Important uncertainties will require more research, including characterizing immunodeficient long-term poliovirus excretor risks, containment risks, and the kinetics of outbreaks and response in an unprecedented world without widespread live poliovirus exposure.

Indias last battle in the war against polio

Knowledge and training in evidence-based medicine is essential for informed clinical decision-making and treatment choices. Systematic reviews identify, appraise and synthesize research-based evidence and present it in accessible format. The Indian Council of Medical Research has promoted evidence-based medicine in India by establishing an Advanced Center for evidence based medicine that hosted the South Asian Cochrane Network and Center at the Christian Medical College, Vellore; procuring a national subscription to The Cochrane Library making it accessible to all Indian scientists; and establishing a Center for Advanced research on evidence-based child health at Post Graduate Institute of Medical Education and Research, Chandigarh. This article informs about a national level initiative by ICMR that aims to harness the translational potential of secondary research, by funding systematic reviews aligned to national health priorities selected through a national competitive process; and to provide training, mentoring, and quality assurance. A continuing scheme of funding high-quality systematic reviews on priority areas of Child Health may follow.

Polio inactivated vaccine costs into routine childhood immunization in Brazil

OBJECTIVE

To analyze the costs of vaccination regimens for introducing inactivated polio vaccine in routine immunization in Brazil.

METHODS

A cost analysis was conducted for vaccines in five vaccination regimens, including inactivated polio vaccine, compared with the oral polio vaccine-only regimen. The costs of the vaccines were estimated for routine use and for the “National Immunization Days”, during when the oral polio vaccine is administered to children aged less than five years, independent of their vaccine status, and the strategic stock of inactivated polio vaccine. The presented estimated costs are of 2011.

RESULTS

The annual costs of the oral vaccine-only program (routine and two National Immunization Days) were estimated at US$19,873,170. The incremental costs of inclusion of the inactivated vaccine depended on the number of vaccine doses, presentation of the vaccine (bottles with single dose or ten doses), and number of “National Immunization Days” carried out. The cost of the regimen adopted with two doses of inactivated vaccine followed by three doses of oral vaccine and one “National Immunization Day” was estimated at US$29,653,539. The concomitant replacement of the DTPw/Hib and HepB vaccines with the pentavalent vaccine enabled the introduction of the inactivated polio without increasing the number of injections or number of visits needed to complete the vaccination.

CONCLUSIONS

The introduction of the inactivated vaccine increased the annual costs of the polio vaccines by 49.2% compared with the oral vaccine-only regimen. This increase represented 1.13% of the expenditure of the National Immunization Program on the purchase of vaccines in 2011.

An ethical framework for public health immunisation programs

This paper presents seven ethical principles associated with the implementation of immunisation programs. For a public health immunisation program to be ethically justifiable, its principles and operation should be based on sound ethical values: the program should benefit the individual and the community; targeted diseases should be sufficiently severe and frequent to justify the risks and expense of the program, and vulnerable groups within the population should be targeted. The principles also deal with the obligation to monitor for adverse events and for disease incidence to ensure safety and effectiveness. When immunisations are voluntary, vaccine recipients or their parents or carers should be given sufficient information to make autonomous, informed decisions and incentives to participate in public health immunisation programs should not be coercive. Public health immunisation programs depend on mutual trust, which may be threatened by circumstances such as excessive media publicity about adverse events associated with vaccines.

Funding of drugs: do vaccines warrant a different approach?

Vaccines have features that require special consideration when assessing their cost-effectiveness. These features are related to herd immunity, quality-of-life losses in young children, parental care and work loss, time preference, uncertainty, eradication, macroeconomics, and tiered pricing. Advisory committees on public funding for vaccines, or for pharmaceuticals in general, should be knowledgable about these special features. We discuss key issues and difficulties in decision making for vaccines against rotavirus, human papillomavirus, varicella-zoster virus, influenza virus, and Streptococcus pneumoniae. We argue that guidelines for economic evaluation should be reconsidered generally to recommend (1) modelling options for the assessment of interventions against infectious diseases; (2) a wider perspective to account for impacts on third parties, if relevant; (3) a wider scope of costs than health-care system costs alone, if appropriate; and (4) alternative discounting techniques to explore social time preference over long periods.

The risks, costs, and benefits of possible future global policies for managing polioviruses

OBJECTIVES

We assessed the costs, risks, and benefits of possible future major policy decisions on vaccination, surveillance, response plans, and containment following global eradication of wild polioviruses.

METHODS

We developed a decision analytic model to estimate the incremental cost-effectiveness ratios and net benefits of risk management options for polio for the 20-year period and stratified the world according to income level to capture important variability between nations.

RESULTS

For low-, lower-middle-, and upper-middle-income groups currently using oral poliovirus vaccine (OPV), we found that after successful eradication of wild polioviruses, OPV cessation would save both costs and lives when compared with continued use of OPV without supplemental immunization activities. We found cost-effectiveness ratios for switching from OPV to inactivated poliovirus vaccine to be higher (i.e., less desirable) than other health investment opportunities, depending on the actual inactivated poliovirus vaccine costs and assumptions about whether supplemental immunization activities with OPV would continue.

CONCLUSIONS

Eradication promises billions of dollars of net benefits, although global health policy leaders face difficult choices about future policies. Until successful eradication and coordination of posteradication policies, health authorities should continue routine polio vaccination and supplemental immunization activities.

The cost-effectiveness of alternative polio immunization policies in South Africa

AIMS

To assess the cost-effectiveness of switching from oral polio vaccine (OPV) to inactivated poliovirus vaccine (IPV), or to cease polio vaccination in routine immunization services in South Africa at the time of OPV cessation globally following polio eradication.

METHODS

The cost-effectiveness of nine different polio immunization alternatives were evaluated. The costs of introducing IPV in a separate vial as well as in different combination vaccines were estimated, and IPV schedules with 2, 3 and 4 doses were compared with the current 6-dose OPV schedule. Assumptions about IPV prices were based on indications from vaccine manufacturers. The health impact of OPV cessation was measured in terms of vaccine associated paralytic paralysis (VAPP) cases and disability adjusted life years (DALYs) averted.

CONCLUSIONS

The use of OPV in routine immunization services is predicted to result in 2.96 VAPP cases in the 2005 cohort. The cost-effectiveness of the different IPV alternatives varies between US$ 740,000 and US$ 7.2 million per VAPP case averted. The costs per discounted DALY averted amount to between US$ 61,000 and US$ 594,000. Among the IPV strategies evaluated, the 2-dose schedule in a 10-dose vial is the most cost-effective option. At the assumed vaccine prices, all IPV options do not appear to be cost-effective in the South African situation. OPV cessation without IPV replacement would result in cost savings of US$ 1.6 million per year compared to the current situation. This is approximately a 9% decrease in the budget for vaccine delivery in South Africa. However, with this option there is a risk (albeit small) of vaccine-derived poliovirus circulating in a progressively susceptible population. For IPV in a single dose vial, the break-even price, at which the costs of IPV delivery equal the current OPV delivery costs, is US$ 0.39.

Current costing models: are they suitable for allocating health resources? The example of fall injury prevention in Australia

The example of fall injury among older people is used to define and illustrate how current Australian systems for allocation of health resources perform for funding emerging public health issues. While the examples are Australian, the allocation and priority setting methods are common in the health sector in all developed western nations. With an ageing population the number of falls injuries in Australia and the cost of treatment will rise dramatically over the next 20-50 years. Current methods of allocating funds within the health system are not well suited to meeting this coming epidemic. The information requirements for cost-benefit and cost-effectiveness measures cannot be met. Marginal approaches to health funding are likely to continue to fund already well-funded treatment or politically driven prevention processes and to miss the opportunity for new prevention initiatives in areas that do not have a high political profile. Fall injury is one of many emerging areas that struggle to make claims for funding because the critical mass of intervention and evidence of its impact is not available. The beneficiaries of allocation failure may be those who treat the disease burden that could have been easily prevented. Changes to allocation mechanisms, data systems and new initiative funding practices are required to ensure that preventative strategies are able to compete on an equal footing with treatment approaches for mainstream health funding.

The cost-effectiveness of pneumococcal conjugate vaccination in Australia

BACKGROUND

Pneumococcal conjugate vaccine, 7 valent (PCV7) is the most costly vaccine yet considered for publicly funded programs. In mid 2001, Australia funded PCV7 for high-risk groups only (indigenous children and children with certain underlying medical conditions). World wide, non-industry-funded studies and studies using cost-utility measures are sparse. We undertook an independent economic analysis of PCV7 compared with no vaccination in the non high-risk Australian childhood population using cost-utility and cost-effectiveness measures.

METHODS

The incidence of invasive pneumococcal disease (IPD), non-bacteraemic pneumonia and otitis media was estimated using representative urban Australian data, or by extrapolation from comparable industrialised countries. A decision-analytic model was developed for a hypothetical birth cohort using the age-specific vaccine coverage from the Californian randomised controlled trial of PCV7. Health outcomes were measured by life-years saved and deaths and disability-adjusted life-years (DALYs) averted. In line with government guidelines, only direct costs were considered in 1997-1998 Australian dollars.

RESULTS

For a birth cohort of 250,000, the gross cost of vaccination is $ 78.6 million. Subtracting treatment cost savings, the net cost (discounted) is $ 61.7 million. In undiscounted terms, vaccination prevents 13.7 deaths, 11.2 (82%) from IPD and the remainder from non-bacteraemic pneumonia. The discounted cost per death avoided is $ 5.0 million, per life-year saved $ 230,130 and per DALY averted $ 121,100, giving a break-even vaccine price of $ 15.40 per dose. These estimates are most sensitive to the unit cost per dose of vaccine, estimates of incidence and vaccine efficacy against non-bacteraemic pneumonia and the discount rate. The cost per DALY reduced to $ 81,000 with a discount rate of 3% rather than 5% and to $ 90,000 with the most favourable assumptions concerning pneumonia reduction.

DISCUSSION

With a vaccine price of $ 90 per dose, mid-range estimates of impact against non-bacteraemic pneumonia, and discount rate of 5%, a PCV7 program for infants not at high risk of IPD is at the upper limit of cost per DALY previously approved under Australian pharmaceutical funding guidelines. The impact of PCV7 against non-bacteraemic pneumonia is poorly defined, but its importance to cost-effectiveness in resource rich and resource poor settings warrants further studies or analysis to give greater precision to this outcome.

Towards global poliomyelitis eradication: the successes and challenges for a developed country

The Sabin oral polio vaccine (OPV) has been remarkably successful, with three major regions of the world declared polio free. Mutations of the live attenuated poliovirus during genomic replication have resulted in polioviruses with increased neurovirulence. Recently, mutated vaccine-derived polioviruses have circulated in countries with low OPV vaccination coverage causing outbreaks of poliomyelitis in the islands of Haiti, the Dominican Republic, the Philippines and Madagascar. Ultimately the total eradication of poliomyelitis requires the cessation of OPV use. The current questions of how best to continue polio immunisation and when OPV should be withdrawn are addressed. Prolonged excretion of poliovirus in stools following cessation of vaccination has the potential to infect unimmunized susceptible children. In Australia the change to the use of inactivated polio vaccine (IPV), while more costly, will avoid the very low risk of vaccine associated paralytic poliomyelitis (one case per 2.5 million doses) and maintain immunity against polio. In the future, new vaccines may provide the solution to the problem of OPV cessation.