Malaria Consortium — ITN Campaign in Ondo State, Nigeria, 2025

Note: This page summarizes the rationale behind a GiveWell grant to Malaria Consortium. Malaria Consortium staff reviewed this page prior to publication.

Published: September 2025

Summary

Background

Malaria is a large driver of under-5 mortality in Nigeria.4 GiveWell believes that distributing insecticide-treated nets (ITNs) is a highly cost-effective intervention to prevent malaria infections and deaths. See our ITN intervention report for background on malaria, its impacts, and what ITNs do.

In August 2024, GiveWell recommended a $13 million grant to Malaria Consortium to support the procurement and distribution of ITNs in Ondo, Nigeria in 2025.

What we think this grant will do

This grant will fund Malaria Consortium to procure and distribute approximately 3.6 million chlorfenapyr-pyrethroid (CFP) ITNs in Ondo state in Nigeria through a mass campaign.5 Ondo is a relatively high burden geography which we believe would otherwise not be served by a mass distribution campaign.

We think this grant will increase the number of people protected against malaria by ITNs and in turn avert ~2,800 child deaths, increase the incomes of protected children later in life, and provide benefits for those over age 5.

Why we made this grant

Our best guess is that this grant will be approximately 16x as cost-effective as unconditional cash transfers (GiveWell’s benchmark for comparing different programs). At the time of writing this page, GiveWell’s funding bar for non-Top Charity grants is 10x or 10 times as cost-effective as cash transfers.6

In simple terms, we think this grant is likely to be cost-effective because:

• Malaria is a major cause of child deaths in Ondo. Our estimate of the under-five mortality rate attributable to malaria (both direct and indirect deaths) is 0.57% in Ondo. (More)
• ITNs provide significant protection against malaria. We estimate that distributing ITNs in Ondo will reduce child malaria mortality by roughly 54%. See our ITN intervention report for more detail on our calculations regarding malaria mortality reductions from ITNs.
• It is relatively cheap to reach people with ITNs. ITNs are relatively cheap to purchase and deliver to households (~$6 per net, adjusted for nets that are unaccounted for).7 Accounting for net use, we estimate that it costs ~$53 per additional child under age five to sleep under a net.8 (More)
• We think most people who access nets through campaigns would not otherwise have access to them. Besides receiving nets through mass distribution campaigns, households may also be able to receive them at antenatal care and infant vaccination visits. Our rough best guess is that 19% of the overall target population for these campaigns would receive nets through one of these routine channels and sleep under a net in the absence of a campaign. (More)
• ITNs probably provide significant benefits beyond averting under-5 mortality. In addition to the primary benefit of averting the deaths of young children, we expect this grant to avert the deaths of ~3,500 older children and adults. We also think that by averting malaria during a sensitive period of childhood development, ITNs could lead to income increases later in life. We estimate that around 27% of the total benefits of this grant come from increased income. (More)
• Without our funding, these campaigns would be unlikely to occur. Our impression is that it is very unlikely that another funder would fill this gap if we didn’t make this grant. Ondo is considered an “orphan state,” meaning that it does not receive funding for mass ITN campaigns from the U.S. President’s Malaria Initiative (PMI) or the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund). (More)

Here is a summary of our cost-effectiveness analysis.

What we are estimating	Best guess (rounded)	Confidence intervals (25-75th percentile)	Implied cost-effectiveness
Campaign cost	$17,870,107
Child mortality benefits
Cost per child reached with ITNs	$29.41	$25.00 - $38.24	20x -13x
Number of children reached	~610,000
Percent of children who would have used ITNs without a campaign	28%	18% - 38%	19x - 15x
Additional children using ITNs as a result of the campaign	~440,000
Years of coverage provided by ITNs	1.8	1.2 - 2.2	12x - 21x
Malaria-attributable mortality rate among people under age five	0.67%	0.33% - 1.00%	8x - 25x
Reduction in malaria mortality from ITN distributions	54%	44% - 65%	13x - 20x
Initial cost-effectiveness estimate
Cost per death averted (child mortality only)	~$6,300
Moral weight for each death averted	116
Initial cost-effectiveness estimate (child mortality only)	6x
Summary of primary benefits (% of modeled benefits)
Reduced child mortality	41%
Reduced mortality among older children and adults	32%
Income increases in later life	27%
Additional adjustments
Adjustment for additional program benefits and downsides	38%	27% - 51%	15x - 18x
Adjustment for grantee-level factors	-4%	(-20%) - (-2%)	14x - 17x
Adjustment for diverting other actors' spending into ITNs ("leverage")	0%
Adjustment for diverting other actors' spending away from ITNs ("funging")	-11%	(-22%) - (-4%)	15x -18x
Overall cost-effectiveness (multiples of cash transfers)	16x

You can see the simple cost-effectiveness analysis for this grant here and the full version here.

The other factors informing our decision to make this grant are:

• Malaria Consortium’s track record of successful implementation. We believe that Malaria Consortium’s past net campaigns funded by GiveWell and implemented in Ondo in 2021 and Anambra in 2022 went fairly well despite challenging logistics (a short planning period and the need to incorporate COVID-19 precautions into distribution plans). While we have some uncertainty about how many nets are unaccounted for and the quality of distribution data generally, we believe that these campaigns achieved fairly high coverage rates (83% in Ondo and 95% in Anambra).9 We think they were highly cost-effective even after accounting for potential net loss (More).
• Potential to learn more about key uncertainties in future campaigns. Malaria Consortium has agreed to modify its monitoring and evaluation (M&E) processes and other data gathering by adding an additional post-distribution monitoring survey shortly after the campaign and annual household surveys to track net ownership and use over time in order to address our uncertainties about campaign impact.10 (More)
• Real funding gap. Our understanding is that Ondo is not currently covered by or likely to become covered by the Global Fund or PMI, which fund net campaigns in other parts of Nigeria. While Ondo has taken out a loan from the World Bank and Islamic Development Bank, we understand that it will use only a small portion of this loan for routine net distribution through antenatal care and infant vaccination visits and will not use any of this funding for net campaigns. (More)

Main reservations

• We have the following reservations about our cost-effectiveness estimates: (More)
  • Over-5 burden of malaria might be overestimated in Ondo. The Institute For Health Metrics and Evaluation (IHME)’s and the World Health Organization (WHO)’s estimates of malaria mortality in sub-Saharan Africa differ, with WHO estimating more under-5 deaths but many fewer over-5 deaths due to malaria than IHME.11 This is particularly concerning in Ondo because over-5 deaths averted make up a larger portion of overall benefits than in the rest of Nigeria,12 so we worry that if WHO is correct, we could be overestimating the program’s cost-effectiveness in this state.
  • We believe that younger, more vulnerable children are likely disproportionately receiving nets from routine sources. We have learned through conversations with stakeholders that Ondo plans to procure enough nets to meet roughly one year of need through the routine distribution channels (antenatal care and infant immunization visits). We have added a 20% downward adjustment for this in our cost-effectiveness model for Ondo, but it may not be sufficient.
• Limited conversations with external stakeholders means we could be missing important considerations. We’ve heard from stakeholders that Ondo is likely to use loans from development banks to fund routine net procurement, procurement of other malaria commodities such as chemoprevention drugs, and immunization programming. From these conversations, it seems that this is because the amount of the loan is not enough to fund a net campaign and because other malaria control initiatives are being prioritized over net campaigns. We have not prioritized investigating exactly why campaigns are not being funded by other actors, so it is possible that we are missing some important considerations. (More)
• Limits on improved M&E. Despite Malaria Consortium’s willingness to implement additional M&E to better account for nets at each stage of distribution, matching households between the distribution data and post-distribution monitoring will likely be imperfect. This means there may still be some number of nets that are unaccounted for. (More)

The organization

Malaria Consortium's seasonal malaria chemoprevention (SMC) program is one of GiveWell's top charities. This grant is the second time we have recommended funding to Malaria Consortium for ITN campaigns. It follows a 2021 grant to Malaria Consortium for support for ITN distribution campaigns in Ondo and Anambra states and a 2020 grant to Malaria Consortium for scoping ITN funding gaps. Additional content on our view of and grants to Malaria Consortium can be found here.

The intervention

ITN distribution campaigns are intended to reduce the burden of malaria by distributing free ITNs to households in areas with high malaria transmission. ITNs are designed to be hung over beds to prevent malaria-carrying mosquitoes from infecting people while they sleep. Mass ITN distributions have been shown to reduce child mortality from malaria and are one of the most cost-effective interventions GiveWell has identified for saving lives. See our intervention report on mass distribution of ITNs for more detail.

The grant

This $13 million grant to Malaria Consortium will support the procurement and distribution of approximately 3.6 million chlorfenapyr-pyrethroid (CFP) ITNs in Ondo state in Nigeria for 2025.

We expect that funds will be used for the following activities:13

• Procuring nets: Following the Nigeria National Malaria Elimination Programme (NMEP)’s selection of net type, Malaria Consortium chooses which net brand to procure,14 creates a campaign budget based on net type and target populations, and then orders nets from their chosen supplier.
• Managing the supply chain: Once nets are ordered, they are shipped to private storage warehouses within states. Malaria Consortium subcontracts transportation of nets to logistics firms.
• Supporting campaign planning: Technical assistants at the Local Government Area (LGA) level plan ITN distribution by gathering ward maps, community lists, ward populations, distribution hub and catchment area locations, and the number of mobilisers and distributors required for each ward.15
• Community engagement: Activities may include radio jingles, live media reporting, town announcements, and a campaign kick-off ceremony. Malaria Consortium’s mobilization and distribution teams may also conduct advocacy visits to state security agencies, government officials, and religious/traditional leaders.16
• Training distributors: Malaria Consortium will train staff at state, LGA, and ward levels on campaign strategy and how to use digital devices for mobile data collection.17
• Household registration and net distribution: Mobilization and distribution teams go to households door-to-door to simultaneously register them, determine how many nets they are eligible to receive based on their household size, and distribute nets to households.18
• Conducting extensive monitoring: Malaria Consortium plans to conduct a number of data collection and monitoring exercises as part of this campaign, including:
  • Non-digital data collection on net quantities throughout the supply chain prior to arrival at state warehouses19
  • Digital data collection on net quantities at state warehouses before distribution and on leftover nets after distribution20
  • Digital data collection on the number of nets distributed to each household, number of household members per household, and household geolocation during distribution21
  • Randomized (but not necessarily consisting of a representative sample) "end-process evaluations" to quickly assess campaign success22
  • Newly for this campaign, Malaria Consortium will also conduct an additional post-distribution survey shortly after distribution (before the existing end-process evaluations and post-campaign household surveys) to mitigate our concerns about nets being unaccounted for, as well as randomized and representative post-campaign household surveys several months after campaigns to assess campaign coverage, net retention, and net use. (More)

Budget for grant activities

Approximately 82% of the total budget for this grant will go to procuring and shipping nets while 11% will support distribution.23

Spending breakdown	Amount	% of total
Procurement and shipping	$14,658,186	82.0%
Distribution	$1,902,302	10.6%
Malaria Consortium staff	$497,819	2.8%
Outcome evaluation surveys	$211,892	1.2%
Management fee	$511,003	2.9%
Contingency	$88,906	0.5%
	$17,870,107	100%

Malaria Consortium has told us that they have ~$4.5 million left over from the previous grant for net campaigns in Ondo and Anambra.24 We have deducted this amount from the total amount required by Malaria Consortium for this campaign to arrive at a grant size of ~$13 million.

The case for the grant

GiveWell recommended this grant because:

• We expect this grant to be highly cost-effective. (More)
• Malaria Consortium has a track record of successful implementation of a previous net campaign in Ondo. (More)
• We think this funding gap is real and that this campaign is unlikely to happen without GiveWell funding. (More)

High cost-effectiveness

Our best guess is that this grant will be 16x as cost-effective as unconditional cash transfers (GiveWell’s benchmark for comparing different programs). At the time of writing this page, GiveWell’s funding bar is to fund grants to non-top charity interventions that we estimate to be 10x or more as cost-effective as cash transfers.25 The main benefit that we expect from this grant is reduced child mortality. Our best guess is that the grant will avert ~2,800 child deaths from malaria in Ondo.

We set out the reasons why we think nets are generally a cost-effective intervention in our separate report on nets. The specific factors driving high cost-effectiveness and main updates we’ve made in the course of this grant investigation are discussed below.

High malaria incidence and mortality

Malaria incidence and mortality are both relatively high (with adjustments) in Ondo compared to other locations for which we have investigated ITN cost-effectiveness. We model the annual malaria mortality rate among 1-59 month olds as 0.33% in Ondo and the total malaria-attributable under-5 mortality rate (including direct and indirect malaria deaths) as 0.57%. By comparison, in Togo, where we guess ITN campaigns are ~9x as cost-effective as unconditional cash transfers, we model the annual malaria mortality rate among 1-59 month olds as 0.19% and the total malaria-attributable under-5 mortality rate (including direct and indirect malaria deaths) as 0.33%. Because ITN campaigns can have a greater impact on reducing malaria incidence and mortality in settings where these baseline rates are relatively high, such as Ondo, we think this campaign is likely to be highly cost-effective.

Higher costs per ITN distributed

We also predict that the cost per ITN distributed will be higher in Ondo as compared to other campaigns we’ve modeled. We think the total cost per ITN distributed will be $5.59 in Ondo as compared to $3.67 in Togo (the country with the lowest cost per ITN distributed of the ones we’ve modeled) and $5.48 in the Democratic Republic of Congo (DRC, the country with the highest cost per ITN distributed of the ones we’ve modeled). These higher costs are primarily driven by using CFP nets for this campaign, which are relatively more expensive than the nets used for other campaigns.26 Accounting for net use, we estimate that it costs ~$41 per additional child under age five to sleep under a net in Ondo.27

CFP nets’ limited susceptibility to insecticide resistance

Insecticide resistance (defined broadly as any ways in which populations of mosquitoes adapt to the presence of ITNs) is a major threat to ITN effectiveness (see the insecticide resistance section of our ITN report here). For this reason, we often include a downward adjustment in our cost-effectiveness models to account for lower ITN efficacy as compared to the original ITN trials, which were conducted before the onset of large-scale insecticide resistance. However, CFP nets are considered to be a type of next-generation ITN that we think are roughly as effective as standard ITNs were during the original trials.28 We model that the higher cost and higher efficacy of CFP nets roughly cancel each other out, so overall cost-effectiveness of CFP nets is roughly equivalent to that of the PBO nets used in the previous campaigns.

Low ITN coverage from routine sources

Based on conversations with external stakeholders, we understand that the number of nets equivalent to around one year of need will be procured in Ondo for routine distribution (through antenatal care or infant vaccination visits).29 Our rough best guess is that 19% of the overall target population for these campaigns would receive nets through routine channels and sleep under a net in the absence of a campaign. Given that we believe the majority of households will not receive nets through routine distribution channels, we think that a net campaign in Ondo will meaningfully increase access to nets.

Malaria Consortium has a strong track record of net campaign implementation

We previously funded Malaria Consortium in 2021 to support ITN campaigns in Ondo and Anambra states. Despite challenging logistics (a short planning period and the need to incorporate COVID-19 precautions into distribution plans), we think these campaigns went quite well overall and were highly cost-effective for the following reasons:

• They achieved relatively high levels of household coverage (95% in Anambra and 83% in Ondo).30
• Cost per net delivered was about 10% lower than forecasted costs.31
• In general, Malaria Consortium’s post-distribution data triangulates well with the national and international data we use in our cost-effectiveness model, which gives us confidence in their data.32

We will have the potential to learn more about key uncertainties in future campaigns

While we judge Malaria Consortium’s monitoring and evaluation (M&E) systems to be relatively strong overall, we have some uncertainty about the number of nets that are being lost at each stage of the distribution process and the quality of distribution data for all of our nets grants (see our Top Charity report on AMF for more detail). Malaria Consortium has agreed to modify its M&E processes and other data gathering by adding the following components for the upcoming Ondo campaign:33

• Immediate coverage survey: Malaria Consortium will add an additional representative household coverage survey shortly after the campaign as a check on the distribution data. We think this would increase our confidence in parameters including the number of nets distributed to households, which is a key input in our cost-effectiveness model.
• Automated checks on distribution data: Malaria Consortium will add a series of automated checks on incoming distribution data to allow them and their partners to flag inconsistencies - both in real time and retrospectively. This may include automated checks on distributors’ geolocation to ensure distributors are distributing nets in the correct locations and timestamp checks to ensure that distributors are not working faster than is realistic. We think that implementing these checks will increase our and Malaria Consortium’s confidence in the distribution data.
• Annual household surveys: Malaria Consortium will conduct annual household surveys to track net ownership and use over time, similar to AMF’s post-distribution monitoring. This will also give us a chance to gauge access to non-campaign nets, which we are unsure about.

We think these campaigns are unlikely to happen without GiveWell funding

Our best guess is that these campaigns are very unlikely (~15% likelihood) to be funded without this grant. From our external conversations, we have not heard anything that indicates other funders’ willingness to fund these campaigns. However, our analysis includes a small adjustment to account for the probability that another funder would fund a program in our absence (“funging”).34

We believe these campaigns are unlikely to be funded without GiveWell support for the following reasons:

• Funding for malaria control, including net campaigns, in most (but not all) states in Nigeria comes from either the President’s Malaria Initiative (PMI) or the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund). However, Ondo does not receive funding from PMI or the Global Fund. We have heard from external stakeholders that it is unlikely that either actor expands its reach into other states as they are both funding constrained.35
• Ondo was supposed to instead receive funding for malaria control from the African Development Bank in 2020, but that loan fell through. This left the state without malaria control funding from any international or multilateral aid agency. We made the 2021 grant in response to this (see here for our understanding of the funding situation as of the time of that grant decision).
• Though Ondo has since signed onto a World Bank/Islamic Development Bank loan, we understand that these funds will be used for broader health system strengthening and some routine net distribution as opposed to net campaigns.36 A representative of Ondo’s State Malaria Elimination Programme (SMEP) told us that he expects this loan will fund around one year’s worth of routine distribution and that Ondo is still a long way from being able to self-fund net campaigns.37

However, there is a chance that we do not have complete information about the funding situation for nets campaigns in Ondo given that we only spoke to Malaria Consortium, Nigeria’s National Malaria Elimination Programme (NMEP), and the SMEP for Ondo when investigating this grant. It is also possible that GiveWell’s presence as a funder reduces the government’s interest in implementing campaigns with its own funds.

Additional benefits

In addition to the primary benefit of averting the deaths of young children, we expect this grant to avert the deaths of a number of older children and adults. This benefit accounts for 32% of the value of this grant.

We also think that by averting malaria during a sensitive period of childhood development, ITNs could lead to income increases later in life. We estimate that around 27% of the total benefits of this grant come from increased income. This is based on two studies that find historical malaria eradication campaigns led to long-term increases in income. We use a combined estimate from these studies and cross reference it against other child health programs that we think lead to income effects (e.g., deworming, iron fortification).

Risks and reservations

Our main reservations about this grant are:

• We have some reservations relating to our cost-effectiveness model, specifically whether over-5 burden of malaria may be overestimated in Ondo and whether younger, more vulnerable children may be disproportionately receiving nets from routine sources. (More)
• Limited conversations with external stakeholders means we could be missing important considerations. We’ve heard from stakeholders that Ondo is likely to use loans from development banks to fund routine net procurement, procurement of other malaria commodities such as chemoprevention drugs, and immunization programming. We have not prioritized investigating exactly why net campaigns are not being funded by other actors, so it is possible that we are missing some important considerations. (More)
• Limits on improved M&E allowing us to fully understand the extent and nature of unaccounted-for nets. Despite Malaria Consortium’s willingness to implement additional M&E to better track unaccounted nets, this will likely be imperfect as it will be difficult to match households between the distribution data and post-distribution monitoring. (More)
• Concerns with ITNs being used for fishing. While these concerns have been raised in the media,38 there is little evidence that this is a widespread problem. For more on our perspective on ITNs being used for fishing, see our separate page on the topic.
• We still have many open questions about ITNs. In 2023, a team of GiveWell researchers “red-teamed” our rationale for ITN grantmaking by searching for possible mistakes and oversights that could impact our recommendations. They identified a number of areas that warrant further research, including insecticide resistance, ITN coverage in the absence of campaigns, and net use. We have not yet thoroughly investigated all of these areas, so we may be missing something.39

Reservations on cost-effectiveness

Over-5 burden of malaria may be overestimated in Ondo

In Ondo, the benefits of ITNs that stem from over-5 deaths averted make up an usually large portion of the grant’s benefits overall compared to other locations we’ve modeled.40 The Institute For Health Metrics and Evaluation (IHME)’s and the World Health Organization (WHO)’s estimates of malaria mortality in sub-Saharan Africa differ, with WHO estimating more under-5 deaths but 50% fewer over-5 deaths due to malaria than IHME. We think that overall, WHO estimates ~15% fewer total deaths from malaria in Nigeria than IHME.41 This is of concern in Ondo because it implies that, if WHO is correct, we could be overestimating the program’s cost-effectiveness. However, we believe that WHO’s estimates are based on a fairly simplistic formula,42 so we put more weight on IHME’s estimates.

Younger, more vulnerable children may be disproportionately receiving nets from routine sources

We have learned through conversations with stakeholders that Ondo plans to procure enough nets to meet roughly one year of need through routine distribution channels (antenatal care and infant immunization visits). As it is pregnant women who would be receiving nets from antenatal care visits and the youngest children are most susceptible to malaria, this could imply that the most vulnerable children are disproportionately receiving nets from routine sources, which would then imply that net campaigns are less cost-effective than we’ve modeled. However, we also heard from one state-level government stakeholder that, in Ondo, nets are given to households at infant immunization visits only when the infant has completed their infant immunization schedule at around two years old.43 We have added a 20% downward adjustment for this in our cost-effectiveness model, but it may not be sufficient.

Limited conversations with external stakeholders means we could be missing important considerations

We’ve heard from stakeholders that Ondo has received a loan from the World Bank and Islamic Development Bank and is likely to use these funds for routine net procurement, procurement of other malaria commodities such as chemoprevention drugs, and immunization programming. From these conversations, it seems that this is because the amount of the loan is not enough to fund a net campaign and because the Nigerian government is prioritizing health system strengthening over campaign-style interventions. Beyond having a limited number of conversations with external stakeholders, we have not deeply investigated exactly why campaigns are not being prioritized or funded by the government or other actors. Therefore, it is possible that we are missing some important considerations.

Limits on improved M&E allowing us to fully understand the extent and nature of unaccounted-for nets

Though we believe Malaria Consortium’s previous ITN campaign in Ondo went well overall and achieved high levels of household coverage (see above), we have some concerns about the number of nets that are being lost at each stage of the distribution process during this campaign. When we compared Malaria Consortium’s distribution data with the data from their subsequent household survey, we noticed that the average number of nets households reported receiving during the household survey was 8% lower than the average number of nets distributors reported giving to households at the time of distribution.44 We also found that the average number of people in a household was substantially higher in the distribution data than in the household survey data; taking the distribution data at face value would imply a population in Ondo that is approximately 25% higher than estimates suggested at the time.45 While Malaria Consortium conducted checks on certain elements of the distribution data during the campaign, we’re not aware of any attempts to systematically validate the number of nets received by households as reported during distribution.46

As outlined above, Malaria Consortium has agreed to implement a number of additional M&E components. However, we believe there are limits on how much this improved M&E will allow us to fully understand the extent and nature of unaccounted-for nets. Our preferred method for validating the distribution data in order to better monitor and understand how many nets are unaccounted for would be an additional household survey conducted shortly after distribution that uses the distribution data as a sampling frame. While households will be matched from the household survey to their distribution data on a number of variables including name of household head, geolocation, and ward and settlement name, matching may still be imperfect as these identifiers may not be exact.

Plans for follow up

• We plan to have bimonthly calls with Malaria Consortium throughout the campaign planning, implementation, and post-campaign evaluation phase, and calls at least every six months thereafter.
• We and Malaria Consortium will collectively align on protocols for the immediate post-campaign surveys, annual household surveys, and automated checks to ensure we are accurately tracking metrics including net ownership, attrition, use, and access to campaign and non-campaign nets over time.
• We will consider a follow-up grant to Malaria Consortium for additional M&E that was not included in this grant, such as malaria incidence monitoring, durability monitoring, and insecticide resistance monitoring. We plan to investigate this grant in Q4 2024.47

Internal forecasts

For this grant, we are recording the following forecasts:

Confidence	Prediction	By time	Resolution
90%	We retrospectively assess CE of the Ondo campaign to be ≥10x.	April 2027	-
90%	Malaria Consortium will implement post-campaign coverage surveys within one month of distributions ending.	July 2025	-
65%	The post-campaign coverage surveys will find coverage to be ≥90% on average.	September 2025	-
60%	We will retrospectively assess cost per net delivered to be below what we currently estimate in Ondo.	April 2027	-
75%	Over the three years covered by this grant, ≤500k nets will be procured for routine distribution in Ondo.	September 2028	-
60%	We make another grant in Ondo for the next round of ITN campaigns.	June 2028	-

Our process

• We had a series of conversations with Malaria Consortium, both virtually and in person.
• We had conversations with representatives of the Nigeria NMEP and Ondo SMEP.
• We reviewed program and evaluation documents from Malaria Consortium’s Ondo and Anambra campaigns in 2021-22.
• We used the ITN cost-effectiveness model from our grant investigation into AMF net campaigns in the DRC in 2025-26, during which we made significant updates to our model, and made corresponding parameter updates for Ondo.
• GiveWell researchers who were not part of the investigation team reviewed the updated cost-effectiveness model for structure, logic, and accuracy.

Sources

Document	Source
DHS Program, Homepage	Source (archive)
GiveWell, 2020 Moral Weights	Source
GiveWell, 2023 GiveWell cost-effectiveness analysis – version 4	Source
GiveWell, Against Malaria Foundation	Source
GiveWell, All Content on Malaria Consortium's Seasonal Malaria Chemoprevention Program	Source
GiveWell, Analysis of Harms from Fishing with Insecticide-Treated Nets	Source
GiveWell, GiveWell's CEA of insecticide-treated net (ITN) distributions --version 24.3 (Ondo grant for 2025)	Source
GiveWell, GiveWell's Cost-Effectiveness Analyses	Source
GiveWell, How We Produce Impact Estimates	Source
GiveWell, Internal forecasts	Source
GiveWell, Making our work more readable	Source
GiveWell, Malaria Consortium — LLIN Funding Gap Scoping	Source
GiveWell, Malaria Consortium — Support for LLIN Distribution Campaigns in Ondo and Anambra States, Nigeria (March 2021)	Source
GiveWell, Mass Distribution of Insecticide-Treated Nets (ITNs)	Source
GiveWell, Our Top Charities	Source
GiveWell, Revisiting leverage	Source
GiveWell, What We Learned From Red Teaming Our Top Charities	Source
Global Fund to Fight AIDS, Tuberculosis and Malaria, Homepage	Source (archive)
Institute For Health Metrics and Evaluation, Global Health Data Exchange	Source (archive)
Malaria Consortium, Anambra household survey, 2023	Unpublished
Malaria Consortium, Budgets for Ondo ITN campaign and campaign evaluation (household surveys) (USD)	Source
Malaria Consortium, Household survey report in Ondo state, 2023	Unpublished
Malaria Consortium, Mop up campaign report for Ondo state, 2023	Unpublished
New York Times, Meant to Keep Malaria Out, Mosquito Nets Are Used to Haul Fish In, Jeffery Gettleman, 2015	Source (archive)
Nigeria National Malaria Elimination Programme, Homepage	Source (archive)
Our World in Data, Malaria deaths: IHME vs. WHO estimates, 2021	Source (archive)
Rethink Priorities, Report on major malaria mortality models	Unpublished
Sarfo et al 2023	Source
U.S. President’s Malaria Initiative, Homepage	Source (archive)
UN Inter-agency Group for Child Mortality Estimation, Homepage	Source (archive)
World Health Organization, World malaria report 2022	Source (archive)

• 1

  The total campaign cost is ~$17.9 million, but Malaria Consortium has ~$4.5 million left over from the previous grant for ITN campaigns in Ondo and Anambra states, so the amount of new funds granted to Malaria Consortium for this campaign is ~$13.4 million. $9.4 million of this grant was funded by Open Philanthropy while $4 million was funded by an individual donor.

• 2

  While the previous grant included Ondo and Anambra states, this grant is only for Ondo. We may investigate ITNs in Anambra alongside other states in Nigeria in 2025.

• 3

  Campaign cost / additional children sleeping under ITNs as result of program: $17,870,107/ 438,112 = $40.79.

• 4

  “In SSA, the burden of malaria amongst [children under 5] varies across various countries. For example, Malaria contributes to more than 30% of [under-5] deaths in Nigeria, and more than 10% in Tanzania [2].” - Sarfo et al 2023

• 5

  Malaria Consortium relayed to GiveWell in unpublished conversations that Nigeria’s National Malaria Elimination Programme has selected chlorfenapyr-pyrethroid (CFP) ITNs to be used in Ondo for the upcoming mass distribution campaign.

• 6

  For more on how we use cost-effectiveness estimates in our grantmaking, see this page.

• 7

  This figure includes our estimate of in-kind government contributions.

• 8

  Campaign cost / additional children sleeping under ITNs as result of program: $17,870,107/ 438,112 = ~$41.

• 9
  • As measured in a stratified random household sample ~3-4 months after the campaign. Household survey reports for both states were provided to GiveWell by Malaria Consortium (unpublished).
  • In Ondo, a mop-up campaign was conducted in September 2023, which resulted in an additional 104,419 households receiving nets based on an unpublished campaign report provided to GiveWell by Malaria Consortium. We estimate that this increased total household coverage in Ondo to ~91%. Our current cost-effectiveness model does not incorporate benefits from the people who received nets during the mop-up campaign.

• 10

  This is based on unpublished conversations between GiveWell and Malaria Consortium leading up to this grant.

• 11

  This is based on an unpublished report from ReThink Priorities on how major modelers estimate malaria mortality.

• 12

  For reference, see this row of our CEA for ITN distributions in several other locations.The percentage of benefits from averted mortalities for those over age 5 ranges from ~21%-23% for other states in Nigeria while we currently model 32% for the same figure in Ondo.

• 13

  These were the activities conducted during the last Ondo ITN campaign; we assume that the same activities will be conducted for the next campaign, but we did not explicitly confirm this with Malaria Consortium beyond confirming that the next campaign will also involve door-to-door net distribution.

• 14

  Malaria Consortium relayed to GiveWell in unpublished conversations that Nigeria’s NMEP has selected chlorfenapyr-pyrethroid (CFP) ITNs to be used in Ondo for the upcoming mass distribution campaign. For the previous nets campaign in Ondo, pyrethroid-piperonyl butoxide (PBO) nets were used. We are not sure what data was involved in the NMEP’s decision to switch from PBO nets to CFP nets. While CFP nets are more expensive than PBO nets, Malaria Consortium believes them to be more durable. Given the net type prescribed by the government, Malaria Consortium can choose which brand to purchase, though certain other specifications like physical dimensions are also dictated by the government. Malaria Consortium told us that they consider a number of factors when selecting a brand, including cost, amount of time to procure, and partner chemical type (e.g. deltamethrin or alphacypermethrin), but cost is generally the most important factor.

• 15

  Source: Malaria Consortium’s report to GiveWell on the previous ITN distribution in Ondo State (unpublished)

• 16

  Source: Malaria Consortium’s report to GiveWell on the previous ITN distribution in Ondo State (unpublished)

• 17

  Source: Malaria Consortium’s report to GiveWell on the previous ITN distribution in Ondo State (unpublished)

• 18

  Source: Malaria Consortium’s report to GiveWell on the previous ITN distribution in Ondo State (unpublished)

• 19

  Source: conversations between GiveWell and Malaria Consortium (unpublished)

• 20

  Source: conversations between GiveWell and Malaria Consortium (unpublished)

• 21

  Source: conversations between GiveWell and Malaria Consortium (unpublished)

• 22

  Source: conversations between GiveWell and Malaria Consortium (unpublished)

• 23

  See the budget for this grant here.

• 24

  According to Malaria Consortium, these savings were due to personnel payments being lower than expected due to changes in the naira-dollar exchange rate (more naira per dollar than expected). In addition, the previous grant included a 5% contingency on the assumption that if it was not used, it would be returned to GiveWell. Since this contingency was not needed for the last campaigns, we have included only a 0.5% contingency for this grant.

• 25

  This benchmark is based on ‘moral weights’, a system we use to quantify the benefits of different impacts (e.g. increased income vs reduced deaths). We benchmark to a value of 1, which we define as the value of doubling someone’s consumption for one year. Our estimate of the value of direct cash transfers is 0.00335 per $. For more on how we use moral weights, see this document.

• 26

  Malaria Consortium relayed to GiveWell that Nigeria’s NMEP has selected chlorfenapyr-pyrethroid (CFP) ITNs to be used in Ondo for the upcoming mass distribution campaign.

• 27

  Campaign cost / additional children sleeping under ITNs as result of program: $17,870,107/ 438,112 = ~$41.

• 28

  This is our understanding based on conversations with experts on ITN effectiveness.

• 29

  Source: conversations with local stakeholders on routine distribution of ITNs and the funding situation for ITN-distribution campaigns (unpublished)

• 30

  As measured in a stratified random household sample ~3-4 months after the campaign. In Ondo, a mop-up campaign was conducted in September 2023, which resulted in an additional 104,419 households receiving nets (unpublished Malaria Consortium mop-up campaign report, pg. 5). We estimate that this increased total household coverage in Ondo to ~91%. Our current cost-effectiveness model does not incorporate benefits from the people who received nets during the mop-up campaign.

• 31

  According to Malaria Consortium, these savings were due to personnel payments being lower than expected due to changes in the naira-dollar exchange rate (more naira per dollar than expected). In addition, the previous grant included a 5% contingency on the assumption that if it was not used, it would be returned to GiveWell. Since this contingency was not needed for the last campaigns, we have included only a 0.5% contingency for this grant.

• 32
  • For counterfactual coverage, Malaria Consortium’s findings are broadly consistent with what we expected based on DHS and other data. They show that use of ITNs was relatively low four months after the campaign (during a relatively hot and dry season), but was higher during the rainy season. Most ITNs still in use had been received in the previous campaign. Consistent with having had a more recent campaign (2017 vs. 2014), Ondo had a higher percentage of households with access to an ITN than Anambra.
  • For net retention, we assume in our model that 94% of nets are still in use at the midpoint of the first year after a campaign, either by the original recipients or by others who have received the nets from the original recipients. In the Anambra survey, approximately 96% of nets were present 3 months after distribution. Of the ~4% of nets that weren’t in use, more than 90% were reported to be used by / given to family elsewhere (which implies that ~99% of nets were retained somewhere). Attrition was higher in Ondo, with 82% of nets still present 4 months after distribution. About 88% of nets not present were reported to be used by / given to family elsewhere (which implies that ~98% of nets were retained somewhere).
  • For number of people per net, we assume 1.7 people sleep under each used net in our model. Malaria Consortium’s post-campaign surveys suggest that, on average, 1.6 people sleep under each used net in Anambra and 1.8 in Ondo. We opt not to adjust for state-level variation in our model given that the figures are quite close and we’re concerned about false precision.
  • For net use, we aggregate DHS/MIS net use survey data to model that 71% of nets are used in Nigeria. In Anambra, Malaria Consortium’s post-distribution household campaign data indicates that 70% of the population slept under an ITN the previous night, with a slightly higher use figure of 72.9% among households with at least one ITN. These surveys took place in November, which is during the rainy season in Nigeria according to Malaria Consortium (Source: Malaria Consortium’s Anambra household survey [unpublished]). Thus, we would expect higher malaria transmission and net use. In Ondo, use as measured in the initial post-campaign household survey was quite a bit lower than our 71% assumption. We think that this is because the initial household survey took place in April, which Malaria Consortium reports is during the dry, hotter, lower transmission season (Source: Malaria Consortium’s Ondo Household survey [unpublished]). Subsequent surveys showed net use increased during rainy, higher transmission seasons.

• 33

  Source: unpublished calls between GiveWell and Malaria Consortium

• 34

  GiveWell defines funging as the possibility that expenditure on a program crowds out funding that would otherwise have come from other sources. If a program would have been funded in GiveWell’s absence anyway, the impact of our funding is likely to be lower than we think (for more on this concept, see here).

• 35

  This is our understanding based on unpublished conversations with a representative of the NMEP.

• 36

  This is our understanding based on unpublished conversations with a representative of the NMEP.

• 37

  Source: unpublished conversation with a representative from Ondo’s SMEP.

• 38

  For example in this New York Times article

• 39

  Since the making of this grant, the findings from our red-teaming have been published. We have not included a discussion of several of the issues that the report raises here as they did not significantly impact our decision-making at the time that this grant was made.

• 40

  In Nigeria Global Fund and PMI states, O5 mortality averted makes up 21% and 23% of benefits overall. In Ondo, this figure is 32% - see here.

• 41

  These figures are based on an unpublished internal analysis, but see also this page from Our World in Data that analyzes this issue.

• 42

  This is based on an unpublished report by Rethink Priorities on major malaria mortality modelers’ methods.

• 43

  This is our understanding based on an unpublished call with a representative of Ondo’s SMEP.

• 44

  Mean of 2.80 nets per household according to the distribution data vs 2.58 nets per household during the household survey conducted four months after distribution.

• 45

  Population of 6,775,577 implied by the distribution data vs Malaria Consortium’s original population assumption of 5,400,000 at the planning stage.

• 46

  Malaria Consortium conducted a rapid end-process monitoring exercise two days after distribution to assess any major gaps in registration and distribution and confirm that the distributed ITNs were retained by households and used, but our understanding is that this exercise was not designed to be statistically representative of the target population. Source: email from Malaria Consortium, July 27, 2024 (unpublished).

• 47

  We made a grant to Malaria Consortium in March 2025 for incidence and physical durability monitoring in Ondo - the full write-up is forthcoming.