What Countries Still Use DDT for Malaria Control?

As of 2023, only three countries were still actively using DDT for malaria control: India, South Africa, and Zimbabwe.¹ That is a dramatic narrowing from the dozens of nations that relied on the chemical in the mid-twentieth century. A handful of other countries still keep DDT registered as an emergency backup, but even among the three active users the amounts have fallen sharply, and the picture shifted again in 2024 when India signaled a major change in its own production.

Why DDT Is Still Legally Available at All

The Stockholm Convention on Persistent Organic Pollutants, which entered into force in 2004, was designed to eliminate twelve of the most persistent and toxic chemicals on the planet. DDT is on that list, but it occupies a unique position: the treaty includes a specific exemption allowing its continued production and use for disease vector control, mainly against the mosquitoes that carry malaria.² The reasoning at the time was straightforward. Malaria kills hundreds of thousands of people a year, predominantly in sub-Saharan Africa and South Asia. For some countries, DDT-based indoor residual spraying (IRS) was the cheapest and most logistically simple tool available. Eliminating access to it before workable replacements were in place could cost lives.

Under the exemption, countries that wish to use DDT must register with the convention’s secretariat and report how much they produce and spray. The exemption is reviewed periodically, and the expectation has always been that countries would transition away from DDT as alternatives became available. That process has been slow and uneven, but by the 2020s the number of registered users had shrunk to a handful.

India as the World’s Sole Producer and Largest User

India has dominated global DDT production and consumption for decades.³ Today, DDT is manufactured at only one facility on Earth: a plant in Rasayani, Maharashtra, operated by HIL (India) Limited, a government enterprise formerly known as Hindustan Insecticides Limited. A second plant in Udyogmandal, Kerala, stopped production in 2018.⁴ Before 2008, China also manufactured DDT for vector control, but it has since exited that market entirely.

The scale of India’s role is hard to overstate. Global production peaked at roughly 6,270 metric tonnes of active ingredient per year in 2005, and global use peaked at about 6,170 metric tonnes in 2008. By 2023, production had fallen to around 309 metric tonnes, a drop of about 95 percent from the peak. Use fell in parallel, down to roughly 369 metric tonnes in 2023.⁴ Most of that steep decline is attributable to India itself cutting back. India had used DDT not only against malaria-carrying mosquitoes but also against sandfly vectors of visceral leishmaniasis, though it stopped using DDT for leishmaniasis control in 2016.

In November 2024, India told the Stockholm Convention secretariat that it had stopped producing DDT for domestic use in mid-2024. Production reportedly continues for export only.⁴ If that holds, it marks a turning point: the country that accounted for the vast majority of DDT spraying over the past two decades is stepping away from using it on its own soil.

South Africa and Zimbabwe

The two other active users in 2023 are both in southern Africa. South Africa has a complicated and well-documented history with DDT. The country switched away from DDT in the 1990s in favor of pyrethroid insecticides, partly in response to growing international environmental pressure. That decision coincided with a devastating malaria resurgence, and by the early 2000s South Africa had reintroduced DDT-based indoor residual spraying in traditional mud-walled houses while using pyrethroids on painted or plastered surfaces. South African delegates were among the strongest advocates during the Stockholm Convention negotiations for preserving the DDT exemption for public health.⁵

Zimbabwe follows a broadly similar pattern, using DDT selectively for IRS in malaria-endemic parts of the country. Both nations use relatively small quantities compared to India’s historical volumes, but their usage has remained fairly constant even as India’s dropped. That creates an odd dynamic: the global decline in DDT use looks dramatic in aggregate, yet outside India the picture has been more of a plateau than a phase-out.⁴

Countries Keeping DDT as a Backup

Beyond the three active users, a few other countries maintain DDT registrations as an emergency option rather than spraying it routinely.¹ The logic is that if a malaria epidemic surges and other insecticides fail because of resistance or supply problems, having DDT in reserve could save lives. These countries are not spraying DDT in normal operations, but they have not fully relinquished their legal right to do so under the Stockholm Convention. The distinction matters because it means the global phase-out is not quite as clean as the “three countries” figure suggests. A sudden change in malaria transmission or insecticide supply chains could push one of these reserve countries back into active use.

Mosquito Resistance and the Problem It Creates

One of the biggest reasons some countries have been reluctant to give up DDT is, paradoxically, also one of the strongest arguments for moving on from it: insecticide resistance. DDT and pyrethroid insecticides, the most widely used class for bed nets and spraying, both target the same site in the mosquito’s nervous system. Mutations in the voltage-gated sodium channel gene, commonly called “kdr” mutations, can make mosquitoes resistant to both chemical classes simultaneously.⁶

This cross-resistance has been documented across sub-Saharan Africa. A large analysis of mosquito populations from across the continent found consistent patterns of shared resistance between pyrethroids and DDT, with DDT showing the strongest association with the kdr mutation frequency in field samples.⁷ The practical consequence is unsettling: in areas where pyrethroids have been used heavily on bed nets, mosquitoes may already be partly resistant to DDT before it is ever sprayed. The same study found no evidence of cross-resistance between the pyrethroid-DDT group and the other two main insecticide classes, carbamates and organophosphates, which is one reason those classes have become more attractive for IRS programs.

Resistance mechanisms go beyond genetics. Research on mosquito populations in Uganda found that while the kdr mutation was the strongest predictor of DDT survival in lab tests, some mosquitoes without the mutation also survived DDT exposure, suggesting additional resistance pathways involving metabolic enzymes like esterases.⁸ Similar multi-mechanism resistance has been seen in Benin, where elevated oxidase and esterase activity appeared alongside rising kdr mutation frequencies.⁹ In short, mosquitoes are evolving resistance to DDT through multiple routes at once, making it progressively less effective in many of the places where malaria is worst.

Newer Insecticides Competing with DDT

The search for replacements has produced several candidates that match or outperform DDT depending on the surface being sprayed. A field trial in South Africa compared DDT against three newer formulations (SumiShield, Actellic, and Fludora Fusion) on the wall types found in real homes. SumiShield significantly outperformed DDT on mud walls and painted cement, achieving higher mosquito kill rates up to twelve months after spraying. DDT actually performed better than Actellic on cement walls and better than Fludora Fusion on tin surfaces, so the picture is surface-dependent rather than a simple across-the-board replacement story.¹⁰

Organophosphate-based sprays have also shown promise. In experimental hut trials against pyrethroid- and DDT-resistant mosquito populations, chlorpyrifos-methyl killed about 95 percent of the malaria vector Anopheles gambiae that entered huts, compared to roughly 50 percent killed by DDT and 31 percent by a standard pyrethroid. The organophosphate also held its potency on sprayed walls for nine months, while DDT and the pyrethroid lost activity within a few months.¹¹ These results give countries concrete options for replacing DDT without losing effectiveness, although cost, supply chains, and regulatory approval still present hurdles.

Does DDT Add Anything Where Bed Nets Are Already in Use?

A question that comes up repeatedly in malaria policy is whether DDT-based spraying is still worthwhile in communities that already sleep under insecticide-treated bed nets. A cluster-randomized trial in The Gambia tested this directly, comparing communities with high long-lasting insecticidal net (LLIN) coverage alone against communities that received both LLINs and DDT-based indoor residual spraying. The trial found no significant difference in clinical malaria incidence or in the density of mosquitoes caught inside houses between the two groups over two transmission seasons.¹² In that particular setting, with moderate seasonal transmission and mosquitoes still susceptible to insecticides, adding DDT spraying on top of nets did not reduce malaria any further.

That result does not mean IRS is never useful alongside nets. The Gambia trial had specific conditions: good net coverage, moderate transmission, and susceptible mosquito populations. In places with higher transmission intensity or where the mosquito species bite during hours when people are not under nets, combining tools could still make a difference. But the trial does suggest that in many settings where net distribution programs are working well, DDT spraying may not be the best use of limited health budgets.

Health and Environmental Concerns in Sprayed Communities

DDT’s persistence is both its appeal and its liability. When sprayed on indoor walls, it can keep killing or repelling mosquitoes for months, which is the whole point. But that same persistence means the chemical and its breakdown products, mainly DDE and DDD, accumulate in soils, water, food, and human tissues. A growing body of research links DDT and DDE exposure to breast cancer, diabetes, reduced semen quality, spontaneous abortion, and impaired neurodevelopment in children.¹³

Studies in communities where DDT is actively sprayed paint a vivid picture of how thoroughly the chemical permeates daily life. In one South African study, DDT and its metabolites were detected in every type of sample analyzed: indoor air, floor dust, outside soil, drinking water, vegetables, and chicken tissue. About four out of five residents in the sprayed village had detectable DDT in their blood serum. Chickens raised in sprayed areas were heavily contaminated, with fat tissue carrying extremely high concentrations.¹⁴ Researchers in a separate study likewise found DDT residues in water, sediment, fish, domestic chickens, and wild birds in a DDT-sprayed region, with the breakdown product DDE consistently the most widespread contaminant.¹⁵

Even after spraying stops, DDT sticks around. Research at a former spraying site in Mexico found that soil concentrations near sprayed homes remained elevated years after the last application, and that chicken eggs contained roughly double the maximum residue limit set by the FAO, with DDE making up about 82 percent of the total.¹⁶ These findings complicate the cost-benefit calculation. For communities in the middle of a malaria crisis, the immediate threat of the disease may outweigh longer-term chemical exposure. But as effective alternatives become available, the environmental and health case for transition grows harder to ignore.

Why Some Households Refuse Spraying

Even in countries that officially endorse DDT-based IRS, not every household welcomes spray teams through the door. Qualitative research in rural Mozambique found that the most common reasons people declined spraying were practical rather than political: key household members were unavailable when the teams arrived, residents disagreed with the procedures involved (such as moving furniture), or people noticed that spraying actually seemed to increase the number of nuisance insects like bedbugs and cockroaches. Most respondents in that study said they preferred bed nets over indoor spraying.¹⁷

Household refusal is a real operational problem for IRS programs of any kind, not just DDT. When enough homes in a community go unsprayed, the community-level protection that IRS is meant to provide gets undermined. Mosquitoes can breed and rest in untreated homes and still reach people in sprayed homes nearby. Programs that rely on DDT face an additional layer of reluctance in some communities because of awareness, however vague, that the chemical is internationally controversial. Whether that awareness translates into higher refusal rates compared to other insecticides is not well established, but the perception matters to program managers trying to achieve high coverage.

Where DDT Stands in 2025

The trajectory is clearer now than it has been in years. India’s mid-2024 halt of domestic DDT production removes the largest single user from the picture, assuming the policy sticks. South Africa and Zimbabwe continue to spray DDT but in modest volumes, and South African researchers are actively testing next-generation insecticides that could replace it on the wall types where DDT currently performs best.¹⁰ The steep global decline since 2008 suggests that actual use may approach zero within a few years, though the convention exemption remains in place and a handful of countries retain DDT as a reserve tool for emergencies.¹ The wild card is insecticide resistance. If newer alternatives falter in the field against increasingly resistant mosquito populations, political pressure to keep DDT available could resurface in countries where malaria still kills tens of thousands of people a year.