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COVAX Part 1: Overview of the fair allocation mechanism

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  • In this post I briefly discuss the current WHO proposal for the global allocation of the COVID-19 vaccines through the COVAX Facility, as well as the February 3 interim distribution forecast for the initial allocation of vaccines to COVAX participating countries. Based on the latest available public information, my calculations for the total dosage needs for the COVAX Facility for the end of 2021 are somewhat less than the official figures (with caveats). On the other hand the national population coverage offered by the initial allocation proposed in the interim forecast does meet the 3% targets stated for the initial distribution during Phase 1 of the allocation plan, but this target could only be met in light of 26% of participating countries not receiving an allocation in this first round.

    Background

    Problems associated with the distribution of limited supplies of COVID-19 vaccines to and within countries are well predicted by a economic theory on competitive markets and public goods. Left un-managed, it is likely that the rich will buy up all the supplies of this precious commodity to the detriment of all others. In global health, this phenomenon even has a name–vaccine nationalism–and has happened in the past and is likely to happen again now that the COVID-19 vaccines have hit the market. While many lower-income countries will struggle to secure supplies of the vaccine over the coming year, a recent Economist Intelligence Unit (EIU) report shows that other, high-income countries have already secured enough doses to vaccinate their populations several times over.

    COVAX Facility

    In response to the threat of vaccine nationalism, a coalition of international partners set up the COVAX Facility in April/May of last year to ensure that all countries–not just the rich ones–would have equal access to vaccines once they become available. Lead by the WHO, GAVI and CEPI among others, COVAX serves as a global purchasing pool that mixes more wealthy “self-financing participant” countries with lower-income publicly funded countries and promises all participants will have access to any the 18 different vaccine candidates being developed in by the pool of pharmaceutical companies in which COVAX has brokered Advanced Market Commitments (AMC). Given that viable vaccines are already on the market as of late-2020, and that more will emerge in the coming months, the big challenge for the COVAX facility is to ensure equitable access and fair allocation across countries.

    In this Part I. blog post, I provide an overview of how the current allocation mechanism works and examine the data from the recently released COVAX distribution plan for the beginning of 2021 (Phase 1). In a follow-up blog post, I examine some commonly mentioned risk factors and country characteristics associated with COVID-19 and some of their implications when used as weighting adjustments for Phase 2 of the COVAX allocation mechanism.

    Data

    The data from this analysis comes primarily from two sources: the public documentation on GAVI’s COVAX Facility website and the latest consolidated country-level COVID data from Our World in Data (OWID). The original documents used for this analysis, along with the extracted data, are saved on my Github repo for ease of use. Additionally, I group countries for analysis using their most recent World Bank Country and Lending groups classifications rather than their WHO regional office groupings.

    COVAX Participation

    At the time of writing, the most recent list of COVAX participants includes 90 committed countries (Self-financing participants + other committed), 6 countries who have submitted a letter of intent but have yet to formally commit, and 92 lower-income countries who are AMC eligible by virtue of their World Bank lending group status, for a total of 188 participating countries. COVAX documentation also cited 8 other non-state participating economies who are not named, thus, they are omitted for the purpose of this analysis.

    ## 
    ##               AMC eligible                  Committed 
    ##                         92                         38 
    ##           Intent submitted Self-financing participant 
    ##                          6                         52

    In the map below, I plot the COVAX participating countries according to these respective categories, and we can see that with very few exceptions (in grey), nearly all countries around the world are committed or have submitted their intent to participate.

    Perhaps and easier way to think about COVAX participation is by referencing the list of countries who are not participating, which is a small group indeed:

    Table 1: Countries not participating in COVAX as of 15 Dec. 2020
    iso_code location
    BLR Belarus
    KAZ Kazakhstan
    LIE Liechtenstein
    RUS Russia
    SMR San Marino
    SYC Seychelles
    TWN Taiwan
    USA United States
    VAT Vatican

    Countries with bilateral agreements for vaccines

    According to the preliminary technical design for the COVAX allocation mechanism, the Facility will request that countries that have successfully concluded bilateral deals with manufacturers to cover a sizable share of their population (e.g. 20%) delay their receipt of COVAX distributed vaccines until other countries receive enough to cover their highest priority populations. While I do not have data on hand for all bilateral deals from all countries, the OWID data includes the total number of vaccinations already administered for each country in advance of COVAX distribution. These countries are indicated in the map above by their ISO abbreviation code. At present, 60 COVAX participant countries have already received vaccines from channels outside of the Facility. The number of total vaccinations already administered for these countries varies widely, as can be seen in the summary statistics below:

    summary(dat_map$total_vaccinations)
    ##     Min.  1st Qu.   Median     Mean  3rd Qu.     Max.     NA's 
    ##       30    49464   305371  1486803   746729 31200000      128

    The COVAX allocation mechanism

    The stated objective of the COVAX Facility is to ensure that enough vaccines are secured so that all participating countries can vaccinate their highest priority populations by the end of 2021, which they estimate to be 2 billion doses in total, of which 1.3 billion doses would go to the 92 lower-income AMC eligible countries.

    The most recent draft of the allocation mechanism (Sep.2020) presents the timing and considerations that will be used to distribute pooled vaccines to participating countries, which are nicely summarized in the figure below:

    Given that supplies will be more limited early on, the allocation mechanism envisions a two phase rollout. In Phase 1, countries will receive vaccines proportional to their population, with doses meant to cover their most vulnerable people, globally estimated to be 20% of the population. Because there will not be enough vaccines early in the year to reach this threshold, the initial round of COVAX vaccine distribution will target 3% coverage of country populations, which is the estimate of the upper-bound share of frontline health-care workers. Additionally, COVAX will keep a percentage of vaccines in reserve as an emergency buffer, which currently is listed to be 10% of the stock.

    While the first phase of the distribution plan is proportional and countries are meant to receive doses at the same rate (to the extent possible), in Phase 2, additional vaccines will be distributed taking into consideration risk factors and needs specific to the countries. All of this, or course, is subject to supply, capacity, and various other constraints that are not detailed in these preliminary plans.

    Phase 1 thresholds

    In the plot above, I sum the populations of the current COVAX participant countries based on the UN’s 2019 Revision of World Population Prospects, and show the coverage needs for the different thresholds, up to 20%. Assuming vaccine needs are estimated as single doses to match population numbers one-to-one, this very simple calculation for 20% coverage for all participants comes to 1.45 billion doses, and 784 million doses for just the 92 AMC countries–both far under GAVI’s estimates of 2 billion and 1.3 billion, respectively. It should be emphasized that my calculations do not include the “8 economies (who are not United Nations Member States)”, nor the emergency buffer, though given the size of the difference in these calculations, it seems unlikely that this would be the only reason for the discrepancies.

    Given that there will unlikely be enough supply to cover all participants, I also estimate the total dosage needs for different participation scenarios (e.g. only committed-countries receiving vaccines, only AMC-countries, countries with no other bilateral agreements, etc.). These alternate scenarios are meant to serve as a reference, as participants receiving allocations–especially early on–will likely be a mix of these different groups of countries and/or be included/not-included for reasons not mentioned here.

    Interim distribution plan

    Last Wednesday, the first interim distribution plan was released, where we can see the initial allocations that are planned for COVAX countries for the first half of this year. As stated in this forecast:

    Total doses cover, on average, 3.3% of the total population of the 145 participants receiving doses from at least one manufacturer in the list detailed below. This is in line with the Facility target to reach at least 3% population coverage in all countries in the first half of the year, enough to protect the most vulnerable groups such as health care workers.

    Table 2: Feb.3 COVAX interim distribution forecast: Total doses (in millions)
    AZ/SII AZ/SKBio Pfizer BioNTech Total doses to be allocated
    227.664 91.2 1.20042 320.0644
    total_interim_doses <- 320064400
    
    #From the total interim doses, I subtract the allocation for Non-UN Member states, and then divide by two to account for double dose regimen
    ((total_interim_doses - 1303200)/2) / sum(dat_dist$population2019) *100
    ## [1] 3.299806

    I’ve extracted the data from the interim forecast and done my own count, which shows 140 countries listed, along with one entry for “Non-UN Member States”. Summing over the proposed country distributions, there are 320 million total doses scheduled in this forecast. When halving that total to account for double-dose requirements, we find that the population coverage comes to exactly 3.3% of the 140 countries listed in the data, more or less matching exactly the GAVI estimate.

    dat_dist <- dat_dist %>% mutate(
      doses_pct = (doses_interim/2)/population2019 * 100
      )
    
    summary(dat_dist$doses_pct)
    ##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
    ##   2.238   2.520   3.854   5.867   3.954  33.229

    With regards to average coverage across all countries for this interim distribution, the numbers show considerable variance in the coverage rate, as can be seen in the summary statistics above. Interestingly enough, we can see that while the minimum coverage provided by the allocated doses for any country is 2.2%, on average, the number is closer 5.9%, with some countries receiving doses up to 33.2% of their population.

    The exact coverage figures are presented in the table below, and in the following section, I plot these results to have a more visual look at the distributions.
    Table 3: Feb.3 COVAX interim distribution forecast: dose coverage as % of population
    iso_code participant AMC population2019 doses_interim doses_pct
    ALB Albania 0 2877800 141600 2.460213
    AND Andorra 0 77265 26400 17.084061
    ATG Antigua and Barbuda 0 97928 40800 20.831631
    ARG Argentina 0 45195777 2275200 2.517049
    ARM Armenia 0 2963234 146400 2.470274
    AZE Azerbaijan 0 10139175 506400 2.497245
    BHS Bahamas 0 393248 100800 12.816340
    BHR Bahrain 0 1701583 100800 2.961948
    BRB Barbados 0 287371 100800 17.538304
    BLZ Belize 0 397621 100800 12.675387
    BIH Bosnia and Herzegovina 0 3280815 177000 2.697500
    BWA Botswana 0 2351625 117600 2.500399
    BRA Brazil 0 212559409 10672800 2.510545
    BRN Brunei Darussalam 0 437483 100800 11.520448
    CAN Canada 0 37742157 1903200 2.521319
    CHL Chile 0 19116209 957600 2.504681
    COL Colombia 0 50882884 2670600 2.624262
    CRI Costa Rica 0 5094114 254400 2.496999
    DOM Dominican Republic 0 10847904 542400 2.500022
    ECU Ecuador 0 17643060 885600 2.509769
    GEO Georgia 0 3989175 214050 2.682886
    GTM Guatemala 0 17915567 847200 2.364424
    IRN Iran, Islamic Rep.  0 83992953 4216800 2.510211
    IRQ Iraq 0 40222503 2018400 2.509043
    JAM Jamaica 0 2961161 146400 2.472003
    JOR Jordan 0 10203140 511200 2.505111
    KOR Korea, Rep.  0 51269183 2713800 2.646619
    LBN Lebanon 0 6825442 340800 2.496542
    LBY Libya 0 6871287 343200 2.497349
    MYS Malaysia 0 32365998 1624800 2.510042
    MUS Mauritius 0 1271767 100800 3.962990
    MEX Mexico 0 128932753 6472800 2.510146
    MCO Monaco 0 39244 7200 9.173377
    MNE Montenegro 0 628062 84000 6.687238
    NAM Namibia 0 2540916 127200 2.503034
    NRU Nauru 0 10834 7200 33.228724
    NZL New Zealand 0 4822233 249600 2.588013
    MKD North Macedonia 0 2083380 103200 2.476745
    OMN Oman 0 5106622 254400 2.490883
    PAN Panama 0 4314768 216000 2.503031
    PRY Paraguay 0 7132530 357600 2.506824
    PER Peru 0 32971846 1770600 2.685018
    QAT Qatar 0 2881060 144000 2.499080
    SAU Saudi Arabia 0 34813867 1747200 2.509345
    SRB Serbia 0 6804596 345600 2.539460
    SGP Singapore 0 5850343 288000 2.461394
    ZAF South Africa 0 59308690 3093000 2.607544
    KNA St. Kitts and Nevis 0 53192 21600 20.303805
    SUR Suriname 0 586634 79200 6.750376
    TTO Trinidad and Tobago 0 1399491 100800 3.601309
    URY Uruguay 0 3473727 172800 2.487242
    VEN Venezuela 0 28435943 1425600 2.506687
    AFG Afghanistan 1 38928341 3024000 3.884060
    DZA Algeria 1 43851043 2200800 2.509404
    AGO Angola 1 32866268 2544000 3.870230
    BGD Bangladesh 1 164689383 12792000 3.883675
    BEN Benin 1 12123198 936000 3.860368
    BTN Bhutan 1 771612 113850 7.377413
    BOL Bolivia 1 11673029 992430 4.250953
    BFA Burkina Faso 1 20903278 1620000 3.874990
    CPV Cabo Verde 1 555988 113850 10.238530
    KHM Cambodia 1 16718971 1296000 3.875837
    CMR Cameroon 1 26545864 2052000 3.865009
    CAF Central African Republic 1 4829764 372000 3.851120
    TCD Chad 1 16425859 1272000 3.871944
    COM Comoros 1 869595 108000 6.209787
    COD Congo, Dem. Rep.  1 89561404 6948000 3.878903
    COG Congo, Rep.  1 5518092 420000 3.805663
    CIV Côte d’Ivoire 1 26378275 2040000 3.866818
    DJI Djibouti 1 988002 108000 5.465576
    DMA Dominica 1 71991 28800 20.002500
    EGY Egypt, Arab Rep.  1 102334403 5138400 2.510593
    SLV El Salvador 1 6486201 375480 2.894452
    SWZ Eswatini 1 1160164 108000 4.654514
    ETH Ethiopia 1 114963583 8928000 3.882969
    FJI Fiji 1 896444 100800 5.622214
    GMB Gambia 1 2416664 180000 3.724142
    GHA Ghana 1 31072945 2412000 3.881190
    GRD Grenada 1 112519 45600 20.263244
    GNB Guinea-Bissau 1 1967998 144000 3.658540
    GUY Guyana 1 786559 100800 6.407657
    HTI Haiti 1 11402533 876000 3.841252
    HND Honduras 1 9904608 496800 2.507924
    IND India 1 1380004385 97164000 3.520424
    IDN Indonesia 1 273523621 13708800 2.505963
    KEN Kenya 1 53771300 4176000 3.883112
    KIR Kiribati 1 119446 48000 20.092762
    PRK Korea, Dem. People’s Rep.  1 25778815 1992000 3.863638
    XKX Kosovo 1 1810366 100800 2.783967
    KGZ Kyrgyz Republic 1 6524191 504000 3.862548
    LAO Lao PDR 1 7275556 564000 3.875992
    LSO Lesotho 1 2142252 156000 3.641028
    LBR Liberia 1 5057677 384000 3.796209
    MWI Malawi 1 19129955 1476000 3.857824
    MDV Maldives 1 540542 113850 10.531097
    MLI Mali 1 20250834 1572000 3.881322
    MHL Marshall Islands 1 59194 24000 20.272325
    MRT Mauritania 1 4649660 360000 3.871251
    FSM Micronesia, Fed. Sts. 1 115021 48000 20.865755
    MDA Moldova 1 4033963 180570 2.238122
    MNG Mongolia 1 3278292 188940 2.881683
    MAR Morocco 1 36910558 1881600 2.548864
    MOZ Mozambique 1 31255435 2424000 3.877726
    MMR Myanmar 1 54409794 4224000 3.881654
    NPL Nepal 1 29136808 2256000 3.871392
    NIC Nicaragua 1 6624554 504000 3.804030
    NER Niger 1 24206636 1872000 3.866708
    NGA Nigeria 1 206139587 16008000 3.882806
    PAK Pakistan 1 220892331 17160000 3.884245
    PNG Papua New Guinea 1 8947027 684000 3.822499
    PHL Philippines 1 109581085 5617800 2.563307
    RWA Rwanda 1 12952209 1098960 4.242365
    WSM Samoa 1 198410 79200 19.958671
    STP São Tomé and Principe 1 219161 96000 21.901707
    SEN Senegal 1 16743930 1296000 3.870059
    SLE Sierra Leone 1 7976985 612000 3.836036
    SLB Solomon Islands 1 686878 108000 7.861658
    SOM Somalia 1 15893219 1224000 3.850699
    SSD South Sudan 1 11193729 864000 3.859304
    LKA Sri Lanka 1 21413250 1692000 3.950825
    LCA St. Lucia 1 183629 74400 20.258238
    VCT St. Vincent and the Grenadines 1 110947 45600 20.550353
    SDN Sudan 1 43849269 3396000 3.872356
    SYR Syrian Arab Republic 1 17500657 1020000 2.914176
    TJK Tajikistan 1 9537642 732000 3.837426
    GIN The Guinea 1 13132792 1020000 3.883409
    TLS Timor-Leste 1 1318442 100800 3.822694
    TGO Togo 1 8278737 636000 3.841166
    TON Tonga 1 105697 43200 20.435774
    TUN Tunisia 1 11818618 686400 2.903893
    TUV Tuvalu 1 11792 4800 20.352781
    UGA Uganda 1 45741000 3552000 3.882731
    UKR Ukraine 1 43733759 2332200 2.666361
    UZB Uzbekistan 1 33469199 2640000 3.943925
    VUT Vanuatu 1 307150 100800 16.408921
    VNM Vietnam 1 97338583 4886400 2.510002
    PSE West Bank and Gaza 1 5101416 277440 2.719245
    YEM Yemen, Rep.  1 29825968 2316000 3.882523
    ZMB Zambia 1 18383956 1428000 3.883821
    ZWE Zimbabwe 1 14862927 1152000 3.875414

    Interim allocation population coverage

    We can see from the data that the coverage rate provided by the interim allocation forecast is not constant across all countries. In this section, I plot these coverage rates, grouped by region, to have a better understanding of the differences.

    In the figure above, I plot the total deaths per million vs the share of the population covered by the interim allocation, broken up by region. The size of the points are scaled by the country’s population.

    It’s clear from looking at the plot that the majority of countries have allocations that cover 2-5% of their populations, and there does not seem to be any relationship between the severity of the mortality rates in-country with the size of the allocation they received. In terms of the countries receiving significantly larger relative shares of the vaccine, by filtering the data for all countries with coverage above 5%, we learn that all of these cases pertain to small countries with populations of less than one million.

    After we drop all countries with populations of over one million people, we can see a very clear negative linear relationship between population size and vaccine coverage from the COVAX allocations, as illustrated in the plot above. As we can also see, this relationship holds across all regions. Most likely, there are practicalities related to shipping or other logistics that makes it impractical to send small countries vaccines 2-3% proportional to their size.

    In fact, when we look at just the countries in the interim allocation forecast with populations of over one million, we find that the mean coverage for all countries is 3.2%.

    summary(dat_dist[dat_dist$population > 1000000, ]$doses_pct)
    ##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 
    ##   2.238   2.510   3.520   3.224   3.872   4.655       6

    Countries with no interim allocations

    From the 188 countries we have on our current COVAX participants list, 48 countries (26%) were not allocated any vaccines in this initial allocation plan. According to the forecast document, these countries “either exercised their rights to opt-out, have not submitted vaccine requests, or have not yet been allocated doses.” The list of participating countries with no initial allocations can be viewed in the table below.
    Table 4: Feb.3 COVAX interim distribution forecast: countries with no initial allocation
    iso_code participant WB_region WB_income_group AMC population2019 doses_interim
    GNQ Equatorial Guinea Sub-Saharan Africa Upper-middle income 0 1402985 NA
    GAB Gabon Sub-Saharan Africa Upper-middle income 0 2225728 NA
    BDI Burundi Sub-Saharan Africa Low income 1 11890781 NA
    ERI Eritrea Sub-Saharan Africa Low income 1 3546427 NA
    MDG Madagascar Sub-Saharan Africa Low income 1 27691019 NA
    TZA Tanzania Sub-Saharan Africa Low income 1 59734213 NA
    ISR Israel Middle East & North Africa High income 0 8655541 NA
    KWT Kuwait Middle East & North Africa High income 0 4270563 NA
    MLT Malta Middle East & North Africa High income 0 441539 NA
    ARE United Arab Emirates Middle East & North Africa High income 0 9890400 NA
    CUB Cuba Latin America & Caribbean Upper-middle income 0 11326616 NA
    AUT Austria Europe & Central Asia High income 0 9006400 NA
    BEL Belgium Europe & Central Asia High income 0 11589616 NA
    BGR Bulgaria Europe & Central Asia Upper-middle income 0 6948445 NA
    HRV Croatia Europe & Central Asia Upper-middle income 0 4105268 NA
    CYP Cyprus Europe & Central Asia High income 0 875899 NA
    CZE Czech Republic Europe & Central Asia High income 0 10708982 NA
    DNK Denmark Europe & Central Asia High income 0 5792203 NA
    EST Estonia Europe & Central Asia High income 0 1326539 NA
    FIN Finland Europe & Central Asia High income 0 5540718 NA
    FRA France Europe & Central Asia High income 0 65273512 NA
    DEU Germany Europe & Central Asia High income 0 83783945 NA
    GRC Greece Europe & Central Asia High income 0 10423056 NA
    HUN Hungary Europe & Central Asia High income 0 9660350 NA
    ISL Iceland Europe & Central Asia High income 0 341250 NA
    IRL Ireland Europe & Central Asia High income 0 4937796 NA
    ITA Italy Europe & Central Asia High income 0 60461828 NA
    LVA Latvia Europe & Central Asia High income 0 1886202 NA
    LTU Lithuania Europe & Central Asia High income 0 2722291 NA
    LUX Luxembourg Europe & Central Asia High income 0 625976 NA
    NLD Netherlands Europe & Central Asia High income 0 17134873 NA
    NOR Norway Europe & Central Asia High income 0 5421242 NA
    POL Poland Europe & Central Asia High income 0 37846605 NA
    PRT Portugal Europe & Central Asia High income 0 10196707 NA
    ROU Romania Europe & Central Asia Upper-middle income 0 19237682 NA
    SVK Slovakia Europe & Central Asia High income 0 5459643 NA
    SVN Slovenia Europe & Central Asia High income 0 2078932 NA
    ESP Spain Europe & Central Asia High income 0 46754783 NA
    SWE Sweden Europe & Central Asia High income 0 10099270 NA
    CHE Switzerland Europe & Central Asia High income 0 8654618 NA
    TUR Turkey Europe & Central Asia Upper-middle income 0 84339067 NA
    TKM Turkmenistan Europe & Central Asia Upper-middle income 0 6031187 NA
    GBR United Kingdom Europe & Central Asia High income 0 67886004 NA
    AUS Australia East Asia & Pacific High income 0 25499881 NA
    CHN China East Asia & Pacific Upper-middle income 0 1439323774 NA
    JPN Japan East Asia & Pacific High income 0 126476458 NA
    PLW Palau East Asia & Pacific High income 0 18092 NA
    THA Thailand East Asia & Pacific Upper-middle income 0 69799978 NA

    The “Team Europe” EU27+ group is on this list, along with most other high-income and upper-middle income countries. There are only 4 low-income/AMC-eligible countries in this list–Burundi, Eritrea, Madagascar and Tanzania–and one would imagine their allocations are pending.

    In addition, 36 of the 60 countries (60%) who have already begun COVID vaccinations in advance of COVAX distribution are included in this list of those who have opted out or are otherwise not receiving initial COVAX allocations.

    Among the other countries who already have bilateral with vaccine manufacturers, it is interesting to see that New Zealand, Chile and Canada have chosen not to withdraw their names from this initial round of distribution despite having already secured enough doses outside of the COVAX platform to vaccinate their populations 2 to 5 times over (see EIU report figure above).

    While COVAX was able to meet its 3% coverage target with this initial allocation plan, this was also done with 26% of COVAX participants not receiving their allocations in this round. Referencing the COVAX Phase 1 allocation needs calculations from above, current supplies put the Facility on the orange dotted line (“All (no bilats)”), far under the total dosages needed to cover all participating countries. It remains to be seen whether enough vaccines will be secured over the remainder of the year to move back to the blue line, where enough supply is on hand to distribute to all participants.

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