Evidence Action's Deworm the World Initiative — Pakistan, Nigeria, and Kenya (February 2022)


In February 2022, GiveWell made a $4.8 million grant to Evidence Action's Deworm the World Initiative. The grant was funded by donations to the Top Charities Fund between October and December 2021. We expect that Deworm the World will use this funding to continue supporting deworming programs in Pakistan ($2.6 million), Nigeria ($1.3 million) and Kenya ($0.9 million). Deworm the World is one of GiveWell's top charities.

We made this grant because we believe the work that the grant will support will be cost-effective. Deworming is among the most cost-effective programs we know of, in certain locations. The need for deworming appears to be high in the areas where Deworm the World expects to use this grant. We have followed Deworm the World's work since 2012, and believe that it is well-positioned to support this work.

Published: March 2022

Table of Contents

Planned activities and budget

This grant will extend support for ongoing programs through 2024.1 We estimate that, prior to this grant, Deworm the World had sufficient funding to support the programs through 2023 and part of 2024.2 The grant size is based on our estimate of the following funding gaps:3

  • $2.6 million for Pakistan
  • $1.3 million in Nigeria for five states: Rivers, Oyo, Lagos, Ogun, and Cross River
  • $0.9 million for Kenya

See here for a discussion of how Deworm the World has spent past funding by spending category. We expect this grant to be spent similarly.

The case for the grant

  • We estimate that this grant will meet our bar for cost-effectiveness. More below.
  • We believe that it is unlikely that another funder will cover these costs. More below.
  • Deworm the World has a track record of supporting successful deworming programs. More in our review of Deworm the World.

A note on how we use cost-effectiveness estimates in our grantmaking

After assessing a potential grantee's room for more funding, we may then choose to investigate potential grants to support the spending opportunities that we do not expect to be funded with the grantee's available and expected funding, which we refer to as "funding gaps." The principles we follow in deciding whether or not to fill a funding gap are described on this page.

The first of those principles is to put significant weight on our cost-effectiveness estimates. We use GiveDirectly's unconditional cash transfers as a benchmark for comparing the cost-effectiveness of different funding gaps, which we describe in multiples of "cash." Thus, if we estimate that a funding gap is "10x cash," this means we estimate it to be ten times as cost-effective as unconditional cash transfers. As of this writing, we have typically funded opportunities that meet or exceed a relatively high bar: 8x cash. We also consider funding opportunities that are between 5 and 8x cash.

Note that our cost-effectiveness analyses are simplified models that do not take into account a number of factors. There are limitations to this kind of cost-effectiveness analysis, and we believe that cost-effectiveness estimates such as these should not be taken literally due to the significant uncertainty around them. We provide these estimates (a) for comparative purposes to other grants we have made or considered making, and (b) because working on them helps us ensure that we are thinking through as many of the relevant issues as possible.


Based on our cost-effectiveness analysis of the program, we believe it is in the range of cost-effectiveness of programs we expect to direct funding to, as of January 2022. Our estimate is that Deworm the World's work in Pakistan is 5x cash, 9-17x cash in Nigeria, and 38x cash in Kenya.4 At the time we recommended this grant, we were primarily looking to recommend grants that we estimated were more than 8x cash, and were willing to consider recommending a limited amount of funding to grants that were between 5x and 8x cash.

Our cost-effectiveness analysis for this grant is based on the same structure as our model for other deworming grants. While investigating this grant, we updated parameters within that model to use inputs specific to this funding gap. Below, we highlight parameters that vary for different funding gaps and have a substantial impact on our headline cost-effectiveness figures:

  • Worm burden: For every deworming grant, we ask the potential grantee to provide data on the prevalence and/or intensity of infections for each species of schistosoma and soil-transmitted helminths in the locations where it would support deworming. We focus on the prevalence of moderate-intensity infections and of heavy-intensity infections for each species, rather than the average infection intensity for each species. We then apply an adjustment to our cost-effectiveness estimates of deworming programs to account for differences between the prevalence and intensity of worm infections in the geographies targeted by our deworming grantees and the prevalence and intensity of worm infections among the population studied in Miguel and Kremer 2004, the randomized controlled trial (RCT) on which we base our estimate of deworming's impact on consumption. Worm burden varies significantly across the areas supported by this grant, and consequently so does this adjustment: from 3% of the level during the RCT to 21%.5
  • Cost per child dewormed: As we've funded these programs in the past, our estimates are based on the results achieved by the programs in 2019 in Pakistan, 2016-2019 in Nigeria, and 2014-2018 in Kenya.6 Cost per child dewormed for these programs ranges from $0.62 in Pakistan to $1.52 in Ogun, Nigeria.7

We estimate that deworming in each of the five states in Nigeria supported by this grant and in Kenya is above 8x cash. We decided to fund the Pakistan program out of our more limited budget for grants we estimate as between 5x and 8x cash.8

Funding landscape

  • Nigeria: The UK government, a major funder of neglected tropical disease (NTD) programs, including deworming, previously funded deworming in parts of Nigeria and ended its support for these programs in 2021. A group of foundations is working to help fill part of the gap left by the UK government's withdrawal. More discussion is on our page for the grant we recommended to fill a portion of this funding gap. We have spoken with representatives of the Bill and Melinda Gates Foundation, Sightsavers, END Fund, the UK and US governments, Children's Investment Fund Foundation, and ELMA Philanthropies about these changes. Based on what we know now, we believe there is a fairly low likelihood that these funders would fund deworming in Deworm the World-supported states in Nigeria.
  • Kenya: Our understanding from following the funding landscape for deworming in Kenya is that the other major funders are supporting localized efforts to interrupt transmission of the parasites targeted by deworming. That said, it is hard to get good information on this because grants recommended by GiveWell have been the primary source of support for the program for several years, so we haven't been able to observe whether this funding gap would be a priority for other funders if we were not funding it. The Children's Investment Fund Foundation was a prior funder but has since shifted its priorities. More in our notes from a conversation with the head of the Division of Vector Borne and Neglected Tropical Diseases in the Kenyan Ministry of Health in December 2020.
  • Pakistan: We are not aware of other potential major sources of funding for deworming in Pakistan. Based on conversations we've had with Deworm the World, our understanding is that there was no national deworming program prior to Deworm the World's support of the program. Dubai Cares provided partial support for the program for three years, but it is not expected to provide additional funding.

Risks and reservations

  • It is possible that through discussions with Deworm the World and other stakeholders, we might have agreed on a scope for the program that would focus on areas within Pakistan that had relatively high worm burden and/or low costs per child, thus raising the cost-effectiveness to above 8x cash. We plan to discuss this possibility with Deworm the World in the future, but didn't think it should hold up this grant. We're not at all sure that it would be better to reduce the reach of the program (in order to grant those funds to another program), but we're interested in understanding more about the options and tradeoffs.
  • In December 2021, Sightsavers (another organization we have supported for its work on deworming) told us the availability of one of the drugs that is often donated to deworming programs, praziquantel, may be changing.9 The World Health Organization, which manages the praziquantel donations, has begun asking countries to request an amount of praziquantel based on plans to target sub-districts, rather than districts, that meet the prevalence threshold for requiring deworming.10 The implications for this grant in particular are not yet clear to us, but may mean that the grant is larger than it needs to be to cover Deworm the World's costs through 2024. We are comfortable with this risk because we expect that Deworm the World will use any extra funding to continue the programs in later years.

Plans for follow up

Deworm the World provides annual updates on program monitoring, results of coverage validation surveys, and spending for each program it supports. It also shares informal updates by email and monthly update calls.

Our process

Our process for this grant relied heavily on (a) our prior work on modeling Deworm the World's cost-effectiveness, and (b) our following Deworm the World's work on the deworming programs we have funded since 2013, including frequent discussions with Deworm the World and reports on program monitoring, coverage achieved, and funding spent. For this particular grant, we revisited worm burden data reports from Nigeria to assess for representativeness of the populations targeted by deworming programs. Over the past six months, we have also spoken with representatives of several funders that work on neglected tropical disease programs (a category that includes deworming programs) about the funding landscape for deworming broadly.


Document Source
GiveWell, Cost-effectiveness analysis – version 1, 2022 Source
GiveWell, GiveWell's estimates of Deworm the World's cost per child dewormed per year [2020] Source
GiveWell, GiveWell's room for more funding analysis for Deworm the World [2021] Source
GiveWell, Summary of GiveWell's 2020 Worm Burden Adjustment Model Source
GiveWell's non-verbatim summary of a conversation with Dr. Sultani Matendechero, December 15, 2020 Source
Miguel and Kremer 2004 Source (archive)
  • 1

    See our projections of funding gaps for Deworm the World's ongoing programs from 2022 to 2024 in this spreadsheet.

    Beyond Pakistan, Nigeria, and Kenya, the spreadsheet includes projected funding gaps for programs in three Indian states (Andhra Pradesh, Madhya Pradesh, and Rajasthan), which will not be supported by this grant. We are discussing those funding gaps with Deworm the World separately.

  • 2
    • See Deworm the World's expected allocation of funding and remaining funding gaps in 2023 and 2024 in this spreadsheet.
    • Deworm the World has been supporting deworming in all locations supported by this grant (see this spreadsheet for a breakdown from 2014-2019), with one partial exception: in Cross River state, Nigeria, Deworm the World previously paused its support due to relatively low cost-effectiveness. Deworm the World is now planning to restart support to Cross River as it believes that its greater scale and experience in Nigeria now will allow it to deliver the program for a lower cost per child. (This is our understanding from multiple conversations with Deworm the World in 2019-2021.) We estimate that Deworm the World has sufficient funding to cover its budget for Cross River in 2022-2023.

  • 3

    GiveWell, GiveWell's room for more funding analysis for Deworm the World [2021], sheet "RFMF projections"

    • Pakistan: $2.57 million
    • Nigeria: $1.32 million = $0.11 (Cross River) + $0.28 (Lagos) + $0.27 (Ogun) + $0.30 (Oyo) + $0.36 (Rivers)
    • Kenya: $0.94 million
    • Total grant size: $4.8 million = $2.57 + $1.32 + $0.94

  • 4

    GiveWell, Cost-effectiveness analysis – version 1, 2022, "Deworm the World" sheet, "Cost-effectiveness in multiples of cash transfers, after all adjustments" row.

  • 5

    GiveWell, Cost-effectiveness analysis – version 1, 2022, "Deworm the World" sheet, "Worm burden adjustment — DtW" row.

  • 6

    See this spreadsheet, "Costs by treatment round" and "Detailed summary" sheets.

    We haven't yet updated these figures through 2020. We consider it a low priority to review the data from 2020 because we expect that it will not be useful for projections of future costs due to short-term disruptions to the programs caused by the COVID-19 pandemic (more on these disruptions in this section of our Deworm the World review). For Kenya, costs have been stable for several years, so we skipped the 2019 update as well.

  • 7

    GiveWell, Cost-effectiveness analysis – version 1, 2022, "Deworm the World" sheet, "Cost per child dewormed (per year) — DtW" row.

  • 8

    See our "Rollover Funding FAQ" page, “Why are GiveWell’s estimates for funds directed to different buckets of cost-effectiveness in 2021 uncertain?” section: "Our current principle is that we’d be willing to spend up to $100m on 5-8x on opportunities we currently believe to be at least 8x that turn out to be 5-8x after further investigation. If we identify more than $100m of 5-8x RFMF, we would either (i) not fund opportunities that exceed the $100m budget, or (ii) the Program Officer leading the investigation would make a case to increase the budget for 5-8x opportunities.”

  • 9

    Conversation with Sightsavers, December 6, 2021 (unpublished)

  • 10

    Conversation with Sightsavers, April 1, 2021 (unpublished)