INSTRUCTOR S NOTE. Copyright 2018, The Johns Hopkins University and Teaching Vaccine Economics Everywhere.

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1 INSTRUCTOR S NOTE This case study can be used to motivate several learning objectives and can be tied to specific course objectives in the modules. In case studies the students are not spoon-fed. Instead, they have to wade through relevant and irrelevant data and identify ways to organize the facts that matter. The orthodox economic paradigm for comparing multiple policies is supposed to be straightforward comparison of an ICER to a country s willingness to pay to avert a DALY. However, these parameters are seldom available. Instructors can use this case study to bring out the basics of estimating ICERs, data quality, budget impact, and the need to understand decision thresholds. This case study could be introduced early in the course to motivate topic matter. Returning after topics have been covered could help to solidify learning. Economic Evaluation Understand the basic concepts of economic evaluation Determine relevant decision criterion Utilize analysis and apply the findings to compare policy decisions Costing of the program / strategies / treatment Decide what costs to include Decide what outcomes to measure Identify appropriate sources of data on cost and outcomes Learn how to use the ICER curve Understand that the ICER curve requires a budget line Health Economics Viewing how vaccines fit into health system building blocks Understand the difference between marginal, average, and total cost Understand that there is no right answer in determining how much should be spent to save a life Explain opportunity costs, monetary benefits, and health outcomes Apply economic decision making principles to realistic case studies

2 Uganda Measles Case Study Authors: David Bishai and Sasmira Matta Background: What is measles? How is Uganda affected? Measles is an acute viral disease that is characterized by a fever, cough, and conjunctivitis, followed by a rash [1]. Case fatality rates are higher in children younger than 5 years and in immunocompromised children, specifically children with leukemia, human immunodeficiency virus (HIV) infection, and severe malnutrition (including Vitamin A deficiency) [1]. Though the prevalence of measles is declining worldwide, measles still presents itself to be an issue in Africa as the average incidence of confirmed measles was 1.9 per 100,000 of the population in 2009 [2]. The WHO-UNICEF accelerated strategy for reducing measles focuses on 47 priority countries that have the highest measles disease burden Uganda is one of these countries [3]. Compared to the African continent s incidence, Uganda s incidence rate is significantly lower at 0.2 per 100,000 as of 2009 [2]. Similarly, the number of reported cases declined last decade from 5,736 cases in 2006 to 1121 cases in 2014 [4]. Despite this decline, it is still of upmost importance that coverage rates be maintained well above 90% since measles outbreaks will occur at lower coverage levels. Photograph from the Public Health Image Library courtesy of the Center for Disease Control and Prevention and Dr. Lyle Conrad. ID: 6887

3 The purpose of this case study is to examine the six different scenarios as suggested by the WHO Expert Group for maintaining high coverage and to determine the best scenario for Uganda. Key Terms and Important Information: A. Vaccine-Related Acronyms In order to fully understand the following scenarios, it is important to understand acronyms that pertain to the measles vaccination. MCV1 means that a child gets a single shot of the measles vaccines at nine months whereas MCV2 means that the child gets 2 shots of the measles vaccine. While the Center for Disease Control indicates that a single dose of the vaccine is 93% effective, two doses prove to be approximately 97% effective [5]. Since the two-dose course of the vaccination is expensive, low-income countries take the risk of a lower effectiveness and often vaccinate children with only one dose. Moreover, Uganda has Supplemental Immunization Activity (SIA) approximately every three years, which is a national campaign where all children, regardless of vaccination status, are administered a measles vaccine. B. Geography Core areas are areas where the children are easy to reach; satellite areas are areas where the children are difficult to reach. C. Types of Costs Total cost is the summation of all of the costs. Average cost is the total cost divided by the total number of products or services. Marginal cost is the additional cost added by producing one additional unit of a product or service. The marginal cost curve depicts an increasing incurred cost as the number of additional units increases. Typically the marginal cost of immunizing one more child starts to rise before the average cost starts to rise. This is because it can be efficient to immunize the

4 closer children first and then immunize the children who are remote or surrounded by violence later. D. Disability Adjusted Life Years (DALY) A DALY can be thought of as one lost year of healthy life [6]. The sum of the DALYs across a population are indicative of the burden of disease and can be thought of as the gap between current health status and an ideal health situation where the population lives free of disease and disability [6]. Therefore, it is important to note that in eradicating and reducing disease prevalence, the goal is to minimize DALYs. IV. Scenarios As of 2010 The MCV1 coverage rate is 68% of 9 month year olds The MCV2 coverage rate is negligible for 9 month year olds The SIA activity indicates a 90% coverage rate of 9 month olds to 5 year olds The best antibody response occurs if measles vaccine is given after the child is 12 months. However, in high risk areas infants are in too much danger if they wait that long, and it is better to give the first dose MCV1 at 9 months and then follow up with a 2nd dose MCV2 at 36 months. The following scenarios 2 through 6, were determined by the WHO Strategic Advisory Group of Experts to be the most attractive to implement in the year Scenario 1: Maintain baseline coverage Scenario 2: Maintain current levels of coverage activities but no SIAs Scenario 3: 95% Mortality Reduction as compared to 2000 Scale up MCV1 by 3% until 2015 Stop SIA in 2014 Scenario 4: 98% mortality reduction as compared to 2000 Ramp up MCV1 by 20% until 2020 Introduce MCV2 for children aged 36 months in 2018 Stop SIAs in 2017 Scenario 5: Eradication of measles by 2020 Ramp up MCV1 coverage by 3% until 2020 Introduce MCV2 for children aged 36 months in 2016 Stop SIA in 2014 Scenario 6: Eradication of measles by 2025 Ramp up MCV1 coverage by 3% until 2025 Introduce MCV2 for children aged 36 months in 2017 Stop SIA in 2017

5 V. Key Figures and Supporting Information The following figures were determined using a simulation that considered resource assumptions to understand what it would take to achieve a higher coverage [7]. Thus these numbers reflect the increased number of community health workers, the number of hours required to reach the children, and expensive logistics[8]. Achieving a higher coverage rate involves more resources, which is more expensive. The average cost per child vaccinated is $1 prior to scale up via routine services The scale up cost per child for core areas is $27 The scale up cost per child for satellite areas is $36 The scale up cost per child for MCV2 in core areas is $9 The scale up cost per child in MCV2 in satellite areas is $27 The SIA cost per child is $.60 Infant mortality from measles is twice as high as that of toddlers and four times as high as that of children and adults The model assumes that children can be easy to reach (i.e. in core areas) or hard to reach (i.e. in satellite areas ) The scale up costs vary between the children in core vs. satellite areas because the kids that have not been reached are harder to vaccinate simply because they are harder to find. Therefore, finding them requires more resources, which translates to more money. Figure III. Costs Associated With Each Scenario

6 Figure IV. Costs vs. Measles DALYs in Uganda for the 6 Scenarios. Incremental Cost Effectiveness Ratios (ICERS) are Interpreted as $ per DALY Averted. Note: The green triangle indicates Scenario 3, which would cost between million dollars to achieve 1.3 million discounted DALYS. VI. Moving Forward The big decision underlying how to proceed in order to maximally boost coverage cannot be answered until a number of smaller decisions are made. Let us suppose that all of the data are going to be presented, and you have the role of the chief of the EPI program. As state above, remember that DALYS are bad they are disability weighted years of life lost. A country wants to have as few of these as possible. Costs, as you already know are also something a country wants less of.

7 Questions: 1) What will you consider in order to pick among the six policies? What matters here? In other words what are important decision criterion to consider? 2) Which scenario would you select to minimize cost? 3) Which scenario would you select to maximize benefit? 4) Which scenario yields the most attractive ICER? 5) How intensive are you going to get your coverage? What are the costs of this? What are the benefits?

8 6) When are you going to drop the SIAs? 7) How much should be spent to save a life? 8) Given the data in this document, what other things do you wish you knew? 9) What alternative options are there to increase coverage? List the pros and cons for each option. 10) Specifically delineate how you are using the cost information to drive decisions.

9 Works Cited 1. Pediatrics, A.A.o., Red Book: 2015 Report of the Committee on Infectious Diseases, B.M. Kimberlin DW, Jackson MA, Long SS, Editor. 2015, American Academy of Pediatrics. p Organization, W.H., AFRO Measles Surveillance Feedback Bulletin UNICEF, W.H.O.a., Measles Mortality Reduction and Regional Elimination Strategic Plan : Geneva. 4. Organization, W.H., Reported measles cases and incidence rates by WHO Member States 2013, 2014 as of 11 February National Center for Immunization and Respiratory Diseases, D.o.V.D. Measles Vaccination. Measles (Rubeloa) 2016 November 22, Organization, W.H. Metrics: Disability-Adjusted Life Year (DALY). Health statistics and information systems. 7. Bishai, D., et al., The cost-effectiveness of supplementary immunization activities for measles: a stochastic model for Uganda. J Infect Dis, Suppl 1: p. S Bishai, D., et al., Technical Appendix for Measles eradication versus measles control: an economic analysis. J Infect Dis, Suppl 1: p. S