ABCDEFGHIJKLMNOPQRSTUVWXY
1
This document was recreated in February 2021 from GiveWell's 2017 preliminary estimate of the cost-effectiveness of measles vaccination (original version can be downloaded here). The "Results" section of the "MAIN" sheet was updated to incorporate our updated moral weights (see "Value assigned to averting the death of an individual under 5 due to measles") and to estimate the relative cost-effectiveness of supplementary immunization activities verses cash transfers. No other aspects of the spreadsheet were updated.

This CEA is significantly less developed than many of GiveWell's published cost-effectiveness analyses. However, as we were unable to identify room for additional funds for measles vaccination of children under 5, we have not further refined or finalized this model.
2
3
1. Inputs
4
5
Inputs for MCV1 coverage, MCV2 coverage, and case fatality ratio are for the following country:
6
Uganda
7
8
9
ParameterInputsParameter explanationKey data sourceFor further explanation and sources, see:
10
MCV1 coverage82.00%Proportion of 9-month-olds who received measles vaccination through routine health systems.WHO/UNICEF Estimates of National Immunization Coverage by country (1980-2013) (HTML)http://www.givewell.org/node/2472 - routineimmunization
11
MCV1 effectiveness85.00%Effectiveness of vaccine at 9mo.Cutts, Grabowsky, and Markowitz 1995, a review of 30 studies of vaccine efficacy in infants under 9 months.http://www.givewell.org/node/2472#vaccine
12
MCV2 coverage0.00%Proportion of children who receive measles vaccination at 18mo or later. SIAs tend to target countries with little or no MCV2 coverage.WHO/UNICEF Estimates of National Immunization Coverage by country (1980-2013) (HTML)http://www.givewell.org/node/2472 - routineimmunization
13
MCV2 effectiveness95.00%Effectiveness of vaccine at >12mo.Demicheli et al. 2012, a Cochrane review of MMR vaccine effectiveness based on three cohort studies.http://www.givewell.org/node/2472#vaccine
14
How many years ago was the most recent SIA?3.00Suggested values: 3 or N/A. A current SIA would have an under-5 target populaion which overlaps with the under-5 target population of any SIA conducted in the last 4 years. Many countries schedule SIAs every 2-4 years depending on measles epidemiology and SIA coverage rate. Select 0, 1, 2, 3, 4 years or N/A.WHO Retrospective Measles Data on Supplementary Immunization Activities 2000-2015 (Excel 262kb)http://www.givewell.org/node/2472#Whatistheprogram
15
SIA coverage90.00%SIAs are often estimated to reach about 95% of their target population. Data on SIA coverage rates is of very limited quality. This parameter is used both for the current SIA under evaluation and for the previous SIA (if applicable).WHO Retrospective Measles Data on Supplementary Immunization Activities 2000-2015 (Excel 262kb)http://www.givewell.org/node/2472#SIAcoverage
16
Under-5 case fatality ratio3.00%Proportion of cases in children under 5 years of age resulting in death. WHO estimates the range of measles CFRs in low-income countries to be between 0.05% and 6%, and between 10% and 30% in complex emergencies or in isolated areas where there is low natural immunity or low vaccination coverage. (We assume case fatality ratio of 0 at ages 5 and up.) The lookup formula returns the lower bound of estimated CFR; see sheet "CFR" column D for upper bounds.Wolfson et. al 2009, a WHO estimate of measles case fatality ratios based on expert opinionhttp://www.givewell.org/node/2472#CFR
17
Annual chance of contracting measles if susceptible30.00%Used in calculating susceptibility (those who have previously contracted measles become immune) and deaths. The WHO Measles Strategic Planning Tool assumes that susceptible individuals have a 30% chance per year of becoming infected with measles, so long as population immunity is less than 90%. We do not include herd immunity effects in this model (e.g. we assume that populations where SIAs occur have not achieved herd immunity). This highly uncertain parameter has a large effect on cost-effectiveness.The WHO Measles Strategic Planning (MSP) Tool, as discussed in Simons et al. 2011http://www.givewell.org/node/2472#infectiousness(Derived): Monthly chance of contracting measles if susceptible3%
18
SIA cost per person targetted (2015USD)2.7We are somewhat uncertain about the cost per person targeted. See discussion and data sources.http://www.givewell.org/node/2472#costhttp://www.givewell.org/node/2472#cost
19
SIA proportion of target population under 5 years of age100%Suggested values: 100%, 33%. Some SIAs ("follow-up SIAs") target only children under five. Others target a wider age range (such as: under-15s). Because death from measles primarily (in this model: only) occurs in children under five, this parameter affects the total cost of an SIA but not the deaths averted. Vary this parameter to model the relative cost-effectiveness of SIAs targeting only under-5s vs SIAs targetting a wider population.WHO Retrospective Measles Data on Supplementary Immunization Activities 2000-2015 (Excel 262kb)http://www.givewell.org/node/2472#Whatistheprogram
20
21
22
2. Calculations
23
24
What proportion of children between 9mo and 5yo are susceptible to measles at the time of the SIA?
25
26
Immunized by surviving measles
27
Age cohort (months)Immunized by MCV1Immunized by MCV2Immunized by prior SIA (depends on SIA year above)Average months alivePortion of susceptibles who have had measles by this ageImmunized by surviving measlesUnimmunizedWeight of age cohort
28
9-1870%ineligibleineligible13.533%10%21%18%
29
18-2170%0%ineligible19.544%13%17%6%
30
21-3370%0%0%2755%16%14%24%
31
33-4570%0%0%3969%20%10%24%
32
45-5770%0%86%5178%3%1%24%
33
57-6070%0%86%58.582%4%1%6%
34
Average chance, if susceptible, of catching measles before reaching age 5:53.14%
35
36
To what extent does an SIA reduce the chance of death from measles of a child under 5?
37
Average susceptibility to measles before the SIA:10.65%
38
Chance (per person) of death from measles before the SIA:0.17%
39
Average susceptibility to measles after the SIA:1.54%
40
Chance (per person) of death from measles after the SIA:0.02%
41
Difference in chance of death due to SIA:0.15%
42
43
3. Conclusions
44
Cost per life saved:$1,859.28
Cost per child under 5 targeted divided by the difference in individual chance of death for a child under 5.
45
46
Value assigned to averting the death of an individual under 5 due to measles120
47
Total units of value generated with hypothetical donation ($100,000)6,454.12
48
Total units of value generated with hypothetical donation ($100,000) to GiveDirectly (unconditional cash transfers)344
49
50
Supplementary immunization activities to prevent measles vs cash18.76
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100