Money flowing back through each stage of the supply chain
In the fields of eastern Uganda, where malaria claims lives with quiet regularity, a plant long celebrated for delighting house cats has revealed a more serious purpose. Cardiff University researchers, working alongside Ugandan colleagues, have found that a lotion made from catnip oil matches the mosquito-repelling power of Deet — the chemical that has anchored global insect defense for decades — at a fraction of the cost. Presented this week in Florence, the findings arrive at a moment when malaria's toll remains staggering and the tools used to fight it are slowly losing their edge. The significance lies not only in the chemistry, but in the possibility that communities most burdened by the disease might one day produce their own protection.
- Malaria killed 610,000 people in 2024 — most of them young children — and infects 282 million annually, making every credible new tool a matter of life and death.
- Commercial Deet repellents remain financially out of reach for rural subsistence farmers in Uganda, leaving one of the most vulnerable populations without consistent protection.
- Field trials in eastern Uganda showed that a 6% catnip oil lotion matched Deet's effectiveness head-to-head, with even a 2% concentration performing only marginally worse.
- The research team has already demonstrated that local community enterprises can manufacture the lotion themselves, keeping economic benefit within the regions most affected.
- Experts caution that topical repellents are only as effective as their consistent use, urging that the catnip lotion be integrated into broader malaria strategies — bed nets, indoor spraying, treatment — rather than deployed as a standalone solution.
On an ordinary evening in eastern Uganda, volunteers rolled up their pant legs and waited while researchers from Cardiff University counted mosquito landings. Some wore Deet, the world's dominant repellent. Others wore a lotion made from catnip — the same plant that sends house cats into euphoric rolling. The results, presented this week at a scientific conference in Florence, were striking: catnip worked just as well.
The active compound is nepetalactone, the molecule responsible for feline delight, which turns out to be deeply repellent to mosquitoes. Scientists had long suspected this, but no one had translated it into a practical, affordable lotion and tested it in a place where mosquitoes genuinely kill people. A 6% concentration of catnip oil matched Deet's field performance; a 2% concentration came close behind. The critical difference is cost — commercial Deet sits beyond the budget of rural subsistence farmers, while catnip can be grown, processed, and sold locally.
Malaria's stakes make the finding urgent. The disease infects roughly 282 million people each year and killed 610,000 in 2024, the vast majority of them children under five. Resistance to both insecticides and treatments is rising, and new tools are needed.
The next phase of the project aims to scale production through local community enterprises — not to enrich researchers, but to create a self-sustaining economic system rooted in the communities where the problem exists. Still, voices of caution have emerged. Research entomologist Swai Kyeba noted that topical repellents are only as powerful as their consistent use, and called for deeper study of how Ugandan households actually apply them before wide rollout. The catnip lotion, promising as it is, works best as one layer in a broader defense — not a replacement for bed nets, indoor spraying, or treatment.
One question the research did not address: whether people wearing catnip lotion would find themselves followed by cats. Dr. Scofield acknowledged, with some humor, that they probably would.
In eastern Uganda, on an ordinary evening, volunteers rolled up their pant legs and waited. Some had smeared themselves with the world's most trusted mosquito repellent. Others wore a lotion made from catnip—the same plant that makes house cats dizzy with pleasure. Researchers from Cardiff University and their Ugandan colleagues then counted how many mosquitoes landed on each person's skin. What they found, presented this week at a scientific conference in Florence, upends a quiet assumption: the herb growing wild in gardens works just as well as the chemical that has dominated global mosquito defense for decades.
Catnip, botanically known as Nepeta cataria, belongs to the mint family. The compound that sends cats into euphoric rolling—nepetalactone—turns out to be deeply unpleasant to mosquitoes. Scientists have known this for years. What they had never done was turn it into a practical, affordable lotion and test it against real mosquitoes on real skin in a place where mosquitoes actually kill people. The trials in Uganda changed that.
Malaria remains a staggering public health crisis. The disease infects roughly 282 million people each year and killed 610,000 in 2024 alone, the vast majority of them children under five in African countries. Mosquitoes carry the parasite. Insecticides kill the mosquitoes. But resistance is rising. The drugs that treat malaria are losing ground too. New tools matter. They matter urgently.
Dr. Simon Scofield, a senior lecturer at Cardiff, explained the logic behind the catnip work with clarity. A six-percent concentration of catnip oil matched Deet's performance in the field trials. A two-percent concentration came close behind, only marginally weaker. But here is the crucial difference: Deet costs money that rural Ugandan farmers do not have. A bottle of commercial mosquito repellent sits outside the budget of subsistence agriculture. Catnip can be grown locally, processed locally, sold locally. The money stays in the community.
The research unfolded in two stages. First, laboratory tests confirmed that catnip oil repelled insects effectively. Then came the field work—the real test. Volunteers in eastern Uganda, some wearing Deet (the standard 15 percent concentration available in the region), others wearing catnip lotion at different strengths, and still others wearing placebo cream, exposed their legs to the evening mosquito population. The researchers simply counted landings. The results held up.
What happens next matters as much as what happened in the trials. The team has already shown that local community enterprises can manufacture the lotion themselves. So far, it has been distributed free, funded by grants. But the next phase will scale production and put it on sale—not to make researchers wealthy, but to create sustainable income for the workers involved in making it. Scofield described the vision: money flowing back through each stage of the supply chain, a self-sustaining system rooted in the place where the problem exists.
Not everyone is ready to declare victory. Swai Kyeba, a research entomologist from Tanzania's Ifakara Health Institute, offered a measured perspective. New, cheap, locally made tools are necessary, he said. But topical repellents have a weakness: people do not use them consistently. They require reapplication. They work best as part of a broader strategy—bed nets, indoor spraying, drug treatment—not as a silver bullet. He called for more research on how Ugandan households actually use repellents before the catnip lotion gets scaled up widely.
One detail Scofield addressed with a touch of humor: whether cats would follow people wearing catnip lotion. The research did not test this. But given that nepetalactone is famous for attracting felines, he expects they would find it quite appealing. For now, that remains an open question—one that sits at the edge of the science, waiting for someone curious enough to ask.
Citas Notables
Deet is out of the price bracket for most rural Ugandan subsistence farmers, so buying commercially available mosquito repellents is just not practicable.— Dr. Simon Scofield, Cardiff University
A challenge with topical repellents is low compliance because they require regular application. This is why they remain a complementary tool in the fight against malaria.— Swai Kyeba, Ifakara Health Institute
La Conversación del Hearth Otra perspectiva de la historia
Why catnip specifically? There must be other plants with insect-repelling compounds.
There are. But catnip is already common in Uganda, easy to grow, and the active ingredient—nepetalactone—is well understood. It's not exotic. It's not something you have to import or synthesize in a lab.
So the real breakthrough is that someone finally tested it properly against Deet in the field?
Exactly. The science of nepetalactone as a repellent wasn't secret. But nobody had made it into a lotion, run controlled trials with real mosquitoes on real skin, and shown it could work at scale in a place where people actually need it.
The cost difference must be enormous.
It is. Deet products are simply out of reach for subsistence farmers. Catnip can be grown in your garden, processed with basic equipment, and sold for pennies. That's the whole point.
But the entomologist from Tanzania raised a fair point—people don't use topical repellents consistently.
He's right. A lotion you have to reapply every few hours is harder to sustain than a bed net you sleep under every night. This works best as one tool among several, not as the answer.
What happens if this actually scales? Could it change malaria prevention in rural Africa?
If the production model works—if communities can make it, sell it, and keep the income—then yes. It could give people an affordable option they can actually access. That's not nothing when you're talking about a disease that kills hundreds of thousands of children a year.
And the cats?
That's the question nobody asked. But I'd expect they'd follow you home.